Patent Application
20180303824
The invention relates to reducing the incidence of tampering and abuse of pharmaceutical products and alcohol, and more particularly to preventing the isolation and concentration of drug constituents for misuse, and preventing excessive intake.
Prescription drug abuse is at epidemic proportions, and has become a serious problem affecting public health worldwide. Pain medications, CNS depressants, and stimulants are among those commonly abused via different techniques including snorting, injection, and co-ingestion with alcohol.
Tablets, transdermal patches, and nasal sprays are the most commonly abused pharmaceutical products and are frequently tampered by crushing and/or mixing with water and alcohol. The initial step of crushing is needed to abuse drugs by almost all routes such as snorting, injecting, smoking, and orally to achieve rapid absorption of the entire dose at once. It is also very common for abusers to take crushed drug products with alcoholic drinks or other beverages to heighten the effects of the drug and allow quicker entry into the bloodstream.
Abuse of prescription drugs is now a fastest-growing drug problem in the US. In almost 10 years, the number of Americans abusing controlled prescription drugs rose from 7.8 million in 1992 to 15.1 million in 2003. This high number of abusers represents more people than the combined total of those abusing cocaine, hallucinogens, inhalants, and heroin. Recent results from the 2009 National Survey on Drug Use and Health report that an average of 7,000 people each day experiment for the first time with a prescription pain medication, tranquilizer, stimulant, or sedative. The large increase in prescribing and abuse of prescription medications has affected public health in many ways. The number of emergency room visits and unintentional deaths due to controlled prescription drugs has increased sharply over the century from 1998 to 2008. Although these medications are generally safe to take as prescribed, they can be deadly when abused, or and taken inappropriately.
Attributed largely to the misuse and abuse of prescription medications, drug poisonings and overdoses now kill more Americans than car accidents for the first time in history. The prescription pain medications have been most responsible for these deaths; as the number of drug poisoning deaths involving such medications has risen from 4,000 in 1999 to 14,800 in 2008, representing over 40% of drug poisoning deaths in 2008.
As more Americans began abusing prescription drugs, so has the number seeking treatment. Every year, from 1999 to 2008, there has been an increase in the number of individuals seeking treatment for opioid prescription pain medications. Along with the increased abuse and treatment of prescription drugs comes rising medical costs. The overall direct cost to health insurers resulting from the nonmedical use of prescription painkillers has been estimated up to $72.5 billion annually.
The abuse and misuse of prescription medications is not limited to the United States. According to the United Nations 2011 World Drug Report, the demand for cocaine, heroin, and cannabis (each an illicit drug) has declined or stayed the same while the production and abuse of prescription opioid pain medications has grown. There are many factors contributing to this widespread abuse. One incentive type factor is the perception that prescription medications are safe and associated with a low potential for harm and abuse compared to illicit drugs. Another factor is the ease of obtaining prescription medications. Many abusers find that prescription medications are much easier to obtain than illicit (street) drugs. A national survey showed that over 70% of people who abused prescription pain medications obtained them directly from friends or relatives, while only 4.3% acquiring them from drug dealers or strangers.
Even though young adults are those most likely to abuse prescription drugs, young adolescent children and older adults abused them too. The abuse of pain medications among adolescents has increased from 3.3% in 1992 to 9.5% in 2004, and stayed close to this level through 2010. Those aged 50 to 59 also showed an increase in abuse from 2.7% in 2002 to 6.2% in 2009. Serious health risks are associated with abuse of these medications in patients over fifty. The number of emergency room visits involving the misuse and abuse of prescription drugs in those aged over 50 increased 121.1% from 2004 to 2008.
The most commonly prescribed medications by physicians are oral tablets and capsules, and they have become the most commonly abused medications. The National Institute on Drug Abuse lists the top three drug classes abused as opioids, central nervous system (CNS) depressants, and stimulants. Opioids are medications similar to morphine (e.g., oxycodone, hydrocodone, codeine), which commonly produce a sense of well-being or euphoria in the abuser. CNS depressants are medications typically used for sleep or anxiety disorders, which cause drowsiness and a calming effect in users. Stimulants are drugs commonly referred to as “uppers”, because they produce alertness and energy with an overall elevation in mood that makes them top candidate drugs for abuse.
When an oral drug no longer gives the same high or euphoric feeling, abusers may take more (overdose), take it in a different way, or manipulate the medication to produce a greater or more rapid euphoria. Altering the medication from its original form for this purpose can be defined as tampering. Tampering typically results in the drug being absorbed at a faster rate or allows the medication to be given by another route. The most common methods of tampering are as follows:
crushing a tablet medication into a powder so that it can be inhaled through the nose and rapidly enter the bloodstream;
once a tablet medication is reduced to small particles by crushing or chewing, it may be taken orally, smoked, snorted, or mixed with a solution and injected for faster results; and
when swallowed with medications, alcohol causes certain drugs to dissolve more quickly and to be absorbed rapidly, which dangerously intensifies the drug's effect on the body. One approach to address the foregoing is Reformulated Oxycontin® (a powerful pain medication). The original Oxycontin tablet was meant to deliver the drug slowly over 12 hours, but abusers quickly found the effect of alcohol in enhancing the drug solubility and that chewing or crushing the tablet could defeat the slow release mechanism. In response, the manufacturer reformulated the product into a similar looking tablet, resistant to crushing into small pieces, forming a thick viscous fluid upon contact with liquids.
REMOXY is a capsule type product containing thick “taffy” like material inside the capsule shell, which purports to slow down drug release. As of this writing, FDA approval has been delayed due to product inconsistency and unpredictable performance.
Embeda® was approved in the U.S. in 2009, and is a capsule that contains small beads of morphine and a segregated compartment which releases a drug upon crushing that stops morphine from working. In 2011, the product was voluntarily recalled for stability reasons and has yet to return to the marketplace. Reformulated Opana® ER (oxymorphone HCl) utilizes a melt extrusion or a thermal process. Exalgo® (Hydromorphone) has a hard exterior shell and gelling agent. Oxecta® (oxycodone HCl) contains gelling agent and a nasal irritant. Nucynta® ER (Tapentadol) uses an approach similar to the reformulated Opana® ER.
Tampering methods such as crushing, chewing, grating, or grinding a dosage form to obtain smaller particles allows the drug to be taken by alternate routes, and speeds the rate of dissolution. For example, crushing a tablet would allow the abuser to snort or smoke the product, or mix with a suitable liquid to dissolve the drug and inject the resultant solution parenterally after filtration. A great concern to public health is when abusers tamper with extend-release formulations containing a large amount of drug meant to be absorbed slowly over several hours. The ability to easily destroy the controlled release mechanisms of these formulations by crushing or other means allows high levels of drug to be absorbed rapidly and to dangerous levels in the user. Tampering of this nature can occur intentionally as in the case of an abuser seeking to get high, or unintentionally by a legitimate user crushing the tablet for ease of swallowing. Drugs and other excipients soluble in ethanol also have the added danger of “dose-dumping”, meaning release of the entire drug load at once, when taken with an alcoholic beverage.
The development of dosage forms intended to deter, discourage and prevent the non-medical use of highly abused drugs was initially made popular by the incorporation of narcotic antagonist into tablet formulations prone to parenteral abuse. Most of these formulations pertain to oral dosage forms, particularly solid dosage forms. First attempts were the use of opioid antagonist that were not orally bioavailable, but would exert their effect if the dosage form was injected by parenteral routes. In the late 1970's, a combination of the prescription drug pentazocine (Talwin®) along with the antihistamine tripelennamine were being used together parenterally to gain a high similar to heroin. To combat this problem, naloxone was included into the formulation, and marketed in the United States as Talwin®Nx. The naloxone in the reformulated tablet was sufficient to antagonize the effects of pentazocine when administered parenterally yet have limited effects when taken orally. The addition of naloxone to tablets was therefore included to deter intravenous abuse. More recently in 2002, the FDA approved the combination of buprenorphine with naloxone (Suboxone®) as a sublingual tablet for the treatment of opioid dependence outside of a clinic. The naloxone component is added to help deter misuse such as parenteral injection during maintenance therapy. Concerns such as the slow dissolution of the sublingual tablets and unintentional child exposures led to the development of oral films with better mucoadhesion and oral dissolution.
U.S. Pat. No. 7,968,119 describes compositions consisting of an opioid agonist together with a sequestered antagonist agent and an antagonist removal system. U.S. Pat. No. 4,457,933 describes combining the analgesic dose of an opioid with a specific low ratio of naloxone. U.S. Pat. No. 6,228,863 describes oral dosage forms that makes extracting an opioid analgesic from the combined agonist/antagonist mixture at least a two-step process. U.S. Pat. Nos. 6,696,088, 7,658,939, 7,718,192, 7,842,309, and 7,842,311 describe tamper-resistant oral dosage forms having a sequestered antagonist. U.S. Pat. No. 7,914,818 describes both a non-releasable sequestered opioid antagonist along with a releasable opioid antagonist together with the opioid agonist.
U.S. Pat. No. 3,980,766 describes adding ingestible solid materials that have rapid thickening properties in water. Compositions containing aqueous gelling agents are described in U.S. Pat. No. 4,070,494. U.S. Pat. No. 6,309,668 describes tablet compositions having two or more layers, where the gelling agent is in a separate layer from the drug. Abuse deterrent dosage forms containing a gel forming polymer along with an analgesic opioid, nasal tissue irritant, and emetic or inert emesis causing agent are described in U.S. Pat. Nos. 7,201,920, 7,476,402, and 7,510,726. Other patents having deterrent agents include U.S. Pat. No. 4,175,119 describing the use of emetic coating, and U.S. Pat. No. 4,459,278 describing binding the emetic agents to an inert sub stance.
In addition to drug abuse, consumption of alcohol is a major public health concern associated with significant costs and high rates of mortality. Three oral medications, i.e. disulfiram (Antabuse®), naltrexone (Depade®, ReVia®) and acamprosate (Campral®) are currently approved to treat alcohol dependence. In addition, an injectable form of naltrexone (Vivitrol®) is also available.
Carbonaceous adsorbents can be modified to produce micro-porous structures giving the material an extremely large surface area. Activated charcoal is an example of carbonaceous material that first undergoes carbonization, and then an activation step to produce a highly porous material capable of adsorption. Activation refers to the development of surface area by increasing pore volume, pore diameter, and porosity of the material through a physical, chemical, or physiochemical activation process. The activation process usually occurs at high temperatures in an environment of an activating gas (e.g. carbon dioxide, steam) or a chemical activating agent (e.g., phosphoric acid, zinc chloride) or both. The raw material to make activated carbon may start from a variety of sources including animal (animal charcoal), natural gas incomplete combustion (e.g., gas black, furnace black), and burning of fats and oils (e.g., lamp black). However, activated charcoal is derived from wood or vegetable origins.
Activated charcoal is a black porous material that is insoluble in water and organic solvents. Commercially, it is available in many forms such as granular, extruded, pelletized or powdered in varying particle sizes. Activated charcoal for medicinal purposes must meet compendial or similar standards (BP, USP), which includes testing to demonstrate its adsorption power. Additionally, it should have a surface area of at least 900 m2/g to have adequate adsorption potential. The properties of activated charcoal are due largely to its enormous surface area and surface chemistry. The average surface area range of activated charcoal is between 800-1,200 m2/g, and may be modified to as large as 2,800-3,500 m2/g. Although the exact mechanisms of interaction between activated carbon and a substrate are complex, adsorption processes are the most well studied, and may be chemical or physical in nature. For the adsorption process in a liquid, activated charcoal acts as the insoluble adsorbent to which a water soluble adsorbate is adsorbed onto. Adsorption may be dependent on polarity, ionization, and environmental pH, with organic and large poorly water soluble materials adsorbing to a higher degree than polar small molecules. Orally, activated charcoal is most notably used as a gastrointestinal decontamination agent to treat acute overdoses and poisonings.
Prescription drug abuse is now a widespread phenomenon, particularly regarding opioid narcotic analgesics. These medications are having alarming effects to public health as the rate of their abuse increases. According to the CDC, drug overdose deaths in the United States have continuously increased for 11 consecutive years in 2010 with opioids being the driving factor and prescription drugs as a whole involved in 60% of cases. Other abusable analgesics such as tramadol have also increased. For example, visits to the emergency room from tramadol overdoses which cause seizures and repository or CNS depression in patients have recently increased. The use of activated charcoal to treat tramadol overdose was investigated in-vitro and in-vivo, and reported to bound up to 0.05 mg of tramadol for each mg of activated charcoal.
Different physicochemical approaches have been experienced by pharmaceutical industry in developing medications with abuse deterrence capability. These include, for instance, prodrug, agonist/antagonist combinations, enzyme inhibition, aversive, coatings, ion exchange, and viscosity-building agents. Oral analgesics, particularly opioids, have been the first drugs incorporated into such formulations. For example, reformulated OxyContin® (oxycodone HCl) utilizes a mechanically strong tablet matrix which can to some extent resist crushing. Reformulated Opana® ER (oxymorphone HCl) utilizes a melt extrusion or a thermal process to become greatly resistant to crushing. In the meantime, the polymer used in these two medications can build great viscosity in an aqueous medium, which makes other processes such as syringeability, filtration, and overall extraction difficult. Embeda® (morphine sulfate/naltrexone) uses agonist/antagonist approach; Exalgo® (Hydromorphone) has a hard exterior shell and gelling agent; Oxecta® (oxycodone HCl) contains gelling agent and a nasal irritant, and Nucynta® ER (Tapentadol) enjoys the same approach as being utilized in reformulated Opana® ER.
Other approaches include the use of polyvinyl alcohol (PVOH). Both chemically and physically-modified Polyvinyl alcohol (PVOH) structures have found applications in biomedical and pharmaceutical areas. Because of its biocompatibility, drug compatibility, water solubility, film forming, good mechanical and swelling properties, the PVOH polymer itself can be found in a variety of pharmaceutical products, including tablets, ophthalmics, implants, transdermal patches and topical creams. Commercial PVOH polymers and copolymers for industrial and pharmaceutical applications include PVA Emprove (from EMD Millipore, Ph Eur (European Pharmacopoeisa), USP is available in a variety of viscosities and grades of hydrolysis to suit various pharmaceutical applications and uses), Selvol™ (Sekisui Specialty Chemicals), Elvanol™ (DuPont), Gohsenol™ (Nippon Gohsei), and Opadry® (Colorcon Inc., graft copolymers of ethylene glycol and vinyl alcohol).
As shown in the art, PVOH solutions have the ability to form gels under repeated freezing and thawing conditions (cryogelation). An aqueous solution of this polymer (even at low concentrations) can be transformed into a solid rubber-like material via a simple freezing-thawing treatment. Upon freezing a PVOH solution, hydroxyl groups (—OHs) of the adjacent polymer chains interact via intra- and inter-molecular forces, creating an ordered water-insoluble structure. The process is favored when the PVOH material is highly de-acetylated, the aqueous PVOH solution is concentrated (up to 20 wt %), and the PVOH molecular weight is in the range 50,000-130,000. There are several articles reporting the freeze-thaw treatment of PVOH solutions at both low and high concentrations, the effect of added salt on the swelling kinetics, the structure/property relationship and the mechanisms of cryotropic gelation of PVOH. A small number of studies have also been focused on osmotic properties, rheological and thermal properties, amount of sol and gel fractions, influence of low molecular weight polyelectrolytes, applications of PVOH cryogels in cell immobilization, applications for protein delivery, and as a strengthening agent in super-porous hydrogels.
Considering that prescription drug abuse and/or alcohol abuse is prevalent and on the rise worldwide, new compositions capable of dettering this abuse would be valuable.
The invention provides various compositions for reducing the incidence of tampering with and abuse of pharmaceutical products and alcohol. These compositions function by preventing the isolation and concentration of drug constituents for misuse and/or preventing excessive intake.
The invention encompasses the use of certain pharmaceutically-acceptable functional polymers, i.e. multifunctional polymers, that are used to make more effective abuse deterrent medications. This disclosure describes different approaches that can potentially deter abuse by reducing the efficacy of main processes utilized by abusers to speed drug absorption and enhance its effect. Pharmaceutical compositions of the disclosure incorporate one or more of the following elements described herein to reduce abuse: super water-absorbency, alcohol absorption, organic binding agents, inorganic binding agents, adsorption, and tough platforms.
As used herein, the term “drug” refers to a pharmaceutically-active ingredient, which is incorporated into a dosage form of the invention. A pharmaceutically-active ingredient is preferably a known drug that is or has the potential to be abused. As used herein, a pharmaceutically-active ingredient is not limited to a drug, but could be any substance capable of being misused and/or abused.
Embodiments disclosed herein are safe and effective if used by regular patients or as prescribed, and are ineffective or less effective in the hand of abusers.
In an embodiment, a pharmaceutical composition of this disclosure is composed of an abusable drug active ingredient, and two primary polymers. The primary polymers utilized in this disclosure are an integral part of the abusable formulation. The first primary polymer, a water-swellable superabsorbent polymer, is a chemically-crosslinked hydrophilic polymer or copolymer, which can at least swell in water to greater than 40 grams per gram of the dry polymer. The water-swellable superabsorbent polymers described herein will change the texture and the flow property of the dosage form in the solution state. Depending on its concentration in the tablet, this polymer significantly reduces the amount of filtrate during the extraction process. The second primary polymer, a plastic agent, is a thermoplastic water-soluble or water-insoluble polymer, which provides a mechanical property to the dosage form in the solid state.
Abusers generally utilize crushing and extraction processes in order to retrieve the high concentration of the active ingredient from the original dosage form. Once crushed, they will either directly abuse it by insufflation, or they add the crushed powder into an aqueous solution or a hydro-alcoholic solution for further extraction of the active ingredient(s).
In one form of abuse, the abuser will use the whole tablet with an ingestion of alcohol. The primary polymers of this disclosure increase the resistance of the tablet to mechanical crushing, and change the solution state of the extraction medium into a solid gel, by which no or minimum drug will be extracted from the abuse-deterred dosage form.
The primary polymers of this disclosure can operate to produce no change, or an insignificant change in the release profile of the active ingredient in the acidic environment of the stomach, when used as intended for a regular patient. Polymers of this disclosure can be physically mixed with the active ingredient to make a matrix tablet, or can be used as a separate layer to make bi- or multiple layer tablets, or can be used in the preparation of other dosage forms.
The invention enables the formation of prescription drugs less likely to be abused by the most common methods of medication tampering. The disclosure addresses each tampering method, and defines a way to lessen its likelihood of occurring. The invention thus targets multiple methods of abuse with the use of one or more polymers that can be incorporated into the current methods of tablet manufacturing.
The following points highlight the theoretical concept and approach for discouraging or preventing each type of tampering method.
CRUSHING: Prospective abusers crush tablets containing potent pharmaceutical ingredients that can directly be snorted into the nose. The active medication is quickly absorbed through the nasal tissue and into the blood stream giving the abuser a quick “high” and a euphoric or desired feeling.
According to an embodiment of the disclosure, primary superabsorbent polymers will be added to tablets, and upon being crushed and inhaled, will swell and form a gel layer when in contact with the wet nasal lining. The changing of dry powder into a gel mass in the nose also “traps” the drug and prevents its quick release into the blood. These two effects are intended to discourage abuse by the nasal route and slow release of the drug into the bloodstream. Moreover the primary plastic agent incorporated into the tablet formulation causes the tablet to be crushed into much larger pieces, and makes the overall crushing process more difficult. As opposed to fine particles, large pieces of crushed tablet with less contact surface area provide a slower drug release into the nasal lining in case of insufflation, and/or act to retard the dissolution and extraction in case of abuse by injection.
INTRAVENOUS (IV) ABUSE: After successfully crushing a tablet containing a drug for abuse, the powder is dissolved in water, alcohol, or other available liquids. The mixture is then filtered to remove any un-dissolved material before being drawn up into a syringe and injected. This results in a large amount of drug entering the body at once and provides the user with a powerful “rush” and euphoric effect.
In accordance with the disclosure, water-swellable superabsorbent polymers can be incorporated into the tablet to deter this type of abuse. After a tablet containing one or more of these polymers is crushed and mixed with an appropriate amount of liquid needed for intravenous injection, the powder in the liquid medium, in a very short period of time turns into a swollen gel that traps the active drug and liquid. The water-swollen mass cannot be filtered using a regular filter paper such as coffee filter paper, or lab filter papers. This approach is therefore designed to impede the ability to abuse a tablet by intravenous injection.
ALCOHOL CO-INGESTION: Swallowing the tablet medication (whole tablet or crushed) with alcohol is commonly experienced to enhance the effect of both drug and alcohol. For those drugs that dissolve in alcohol, this act also gives the user a quicker euphoric feeling since the drug can dissolve and enter the bloodstream more quickly.
In accordance with the disclosure, alcohophilic superabsorbent polymers can be added to the tablet, which when swallowed with alcohol, absorb and trap both alcohol and the dissolved drug so its quick absorption and euphoric effects are less likely to occur.
The inventors have determined that advantageous polymer properties for abuse deterrent applications include characteristics for 1) interacting with moisture in the air when exposed from a crushed tablet, 2) swelling and gelling in water and hydro-alcoholic solutions which are used by abusers to tamper with the medication, and 3) absorbing alcohol and soluble drug when medication is co-ingested with alcoholic beverages.
Polymers with great affinity for water tend to display the least affinity for alcohol, and vice versa. Alternatively stated, a polymer that absorbs significant amounts of water or significantly increases the viscosity of an aqueous solution, will experience a very weak interaction with water if alcohol is added into an aqueous solution. The disclosure identifies specific types of polymers with moderate affinity for both water and alcohol, and/or polymer combinations where one has good affinity for water and the other a good affinity for alcohol.
In accordance with the disclosure, primary superabsorbent polymers advantageously can be: made of very hydrophilic monomers, ionics and non-ionics; chemically crosslinked; absorbent of an aqueous medium rich in water; absorbent of an aqueous medium rich in alcohol; and very hygroscopic. In addition, they can: form an integral part of the formulation; prevent crushed medication particles from becoming free flowing under any abusable action such as snorting; effectively prevent filterability and impede the ability to abuse a tablet by intravenous injection; trap the drug dissolved in the hydroalcoholic solution and prevent its rapid absorption and euphoric effects when swallowed with alcoholic beverages.
Examples of such polymers include crosslinked polymers, copolymers and terpolymers of water-soluble monomers of sodium acrylate, potassium acrylate, sodium methacrylate, potassium methacrylate, potassium sulfopropyl acrylate, acrylamide, 2-acrylamido 2-methyl 1-propane sulfonic acid (AMPS), and methacrylamidopropyltrimethyl ammonium chloride.
Superabsorbent polymers of this disclosure include crosslinked poly(sodium acrylate), crosslinked poly(sulfopropyl acrylate potassium), crosslinked polyacrylamide, crosslinked copolymer of acrylamide and sodium acrylate. Synthetic polymers of this disclosure can be prepared following a general experimental procedure that we previously reported which are incorporated herein by reference, or their purified commercial counterparts can be used instead.
An additional component includes a primary plastic agent, which advantageously: is soluble or insoluble in water; has good thermoplastic properties; and has binding and adhesion properties. Additionally, the plastic agent should be capable of being processed at relatively low temperature in order to avoid drug thermal decomposition. The inventors have found these materials generally have glass transition temperature at around 35-55° C.
Plastic agents used in this disclosure can be blends of polyvinyl acetate and other polymers, or copolymers of vinyl acetate and other monomers.
While the foregoing primary polymers can provide sufficient performance to deter abuse, secondary polymers, which can serve as superviscosifier polymers, can be advantageously used along with the primary polymers to enhance the deterrence capacity of the dosage form. A superviscosifier is a very high molecular weight polymer with great affinity for both water and alcohol. In other words, a superviscosifier can provide significant viscosity in both aqueous and hydroalcoholic (very rich in alcohol) solutions.
Secondary polymers (Superviscosifier polymers) are advantageously made of very hydrophilic monomers, ionic and non-ionics; are not chemically crosslinked; enhance viscosity of the aqueous medium rich in water; and enhance viscosity of the aqueous medium rich in alcohol. Their function can be only to enhance the efficacy of the primary polymers used in the formulation. The secondary polymers contribute to preventing filterability and impeding the ability to abuse a tablet by intravenous injection.
Examples of such polymers include polyethylene oxide, methyl cellulose, hydroxypropyl methylcellulose, carboxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, guar gum, and xanthan.
In the examples, tramadol and dextromethorphan HBr are used a representative of a pharmaceutically-active ingredient. It should be understood that other drugs can be used, as described elsewhere herein.
The terms “a” or “an”, as used herein, are defined as one or more than one. The term plurality, as used herein, is defined as two or more than two. The term another, as used herein, is defined as at least a second or more. The terms “including” and “having,” as used herein, are defined as comprising (i.e., open language). The term “coupled,” as used herein, is defined as “connected,” although not necessarily directly, and not necessarily mechanically.
As used herein, the term “about” means plus or minus ten (10) percent of the stated numerical value.
The phrase “pharmaceutically-acceptable excipient” refers to an inactive and non-toxic substance used in association with an active substance usually to prepare a dosage form.
Other objectives and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying drawings, wherein are set forth, by way of illustration and example, certain embodiments of this invention. The drawings constitute a part of this specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof.
A more complete understanding of the present invention may be obtained by references to the accompanying drawings when considered in conjunction with the subsequent detailed description. The embodiments illustrated in the drawings are intended only to exemplify the invention and should not be construed as limiting the invention to the illustrated embodiments.
As required, detailed embodiments are disclosed herein; however, it is to be understood that the disclosed embodiments are merely examples and that the systems and methods described below can be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present subject matter in virtually any appropriately detailed structure and function. Further, the terms and phrases used herein are not intended to be limiting, but rather, to provide an understandable description of the concepts.
The examples serve the purpose of promoting an understanding of the principles of the invention. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended. Any alterations and further modification in the described compositions, tablets, formulations, and methods and any further application of the principles of the invention as described herein, are contemplated as would normally occur to one skilled in the art to which the invention relates.
Crush resistance and viscosity building are the two most common physicochemical characteristics that have been utilized in formulating abuse-deterrent medications, and to achieve both, very high molecular weight polyethylene oxide (PEO) has been used. It has a very simple structure, potentially least interaction with drug and other excipient, it builds great viscosity in water and hydro-alcoholic solutions, and it melts at relatively low temperature in its solid state. However, low melting temperature of its solid state, shear-dependent viscosity of its solution state, salt and light sensitivity are among disadvantages that need to be taken into consideration when polyethylene oxide is used as deterrent. Moreover, it has very slow dissolution kinetics in aqueous systems; in fact its complete dissolution in water may take hours if no provision is taken to expedite the process.
PEO concentration in tablets with deterrence potential can be as high as 200-300 mg per tablet, and the amount of liquid that abusers use to extract the drug from the tablet can be as average as 10 mL. At such high concentration of PEO in an aqueous medium (2-3 wt. %), the PEO solution turns into a PEO gel for which gel strength can alternatively be measured.
250 mg of PEO WSR coagulant was dissolved in respective solutions (water, normal saline, 20% ethanol or EtOH 20%, and 40% ethanol or EtOH 40%) and kept overnight for complete and homogeneous dissolution. For the hydrocholoric acid (HCl) study, the solution pH of PEO in water was changed to 1 using concentrated HCl. The gel strengths were measured on Texture Analyzer (CT3, Brookfield Engineering). A spherical probe was attached to the shaft and was moved into the sample at the speed of 2 mm/sec. Once it reached the trigger load, the probe moved to a distance of 4 mm into the gel at the speed of 0.5 mm/sec, and the magnitude of load at the target was measured. The gel strength data shows average gel strength of about 34 mN in water, saline, EtOH 20% and EtOH 40%. The PEO gel strength in 0.1N HCl medium was found insignificant. Results are illustrated in
Drug Release from Representative PEO Tablets:
Tablets containing 25 mg of tramadol HCl, 250 of PEO (WSR coagulant), and Prosolv® SMCC were prepared using a Carver press at 1000 pound force. The tablets prepared were studied for dissolution profile in distilled water and 0.1N HCl at 370 C @ 50 rpm. Samples were drawn at specific time points, and drug concentration was determined using a UV-spectrophotometer @271 nm.
Based on the dissolution data, a tablet containing 250 mg of high molecular weight PEO would offer very similar sustained release profiles in water and 0.1N HCl solutions (ANOVA p value of 0.674). Results are illustrated in
The data presented for PEO drug release and gel strength show that hydrochloric acid plays a major role in gel strength with lesser effect on drug release. The instant invention offers an alternative method of abuse deterrence where the hydrochloric acid plays a major role in drug release from abuse-deterrent compositions.
Materials: Materials examined in this disclosure are tramadol HCl, sodium carboxymethyl cellulose (Ticalose® 6000 from TIC Gums, and Akucell® from AkzoNobel), aluminum chloride hexahydrate, aluminum hydroxide, zinc acetate, talc, and Prosolv® SMCC (silicified microcrystalline cellulose, JRS Pharma).
Carboxymethylcellulose (250 mg) was dissolved in hydro-alcoholic solutions (60%, 65%, 70%, 90% and pure ethanol) containing 25 mg of tramadol HCl. The solution was centrifuged @1500 rpm for 5 min, then filtered through a 0.2 μm syringe filter; 0.5 ml of the supernatant solution was diluted with 10 ml of solvent, and then analyzed for drug concentration by UV spectroscopy @271 nm. Results are illustrated in
Aluminum chloride and sodium carboxymethylcellulose (CMC) were weighed and mixed in a glass mortar. 10 mL of distilled water was added to physical mixture. Rapid gelation was observed within a few seconds. Gels were transferred to 20 mL glass vial and gel strengths were measured on Texture Analyzer (CT3, Brookfield Engineering). A spherical probe was attached to the shaft and moved into the sample at the speed of 2 mm/sec. Once it reached the trigger load, the probe moved to a distance of 4 mm into the gel at the speed of 0.5 mm/sec, and load at the target was measured. Results are illustrated in
As shown in Table 1, and as illustrated in
Two different grades of Sodium CMC (Akucell® AF0305 and Ticalose® 6000) were studied for their gel strength in different solvents including water, normal saline, 20% ethanol (EtOH 20%), 40% ethanol (EtOH 40%), and 0.1N HCl, as shown in Tables 2 and 3.
Further in accordance with the disclosure, and with reference to
Tables 4 and 5 illustrate gel strength data of sodium CMC (Ticalose 6000) in different media.
With reference to Tables 4 and 5, and
With reference to
With reference to
With reference to
Four formulations were prepared to represent immediate and sustained drug release compositions. Individual components were weighed and mixed using a glass mortar and pestle. The mixture was compressed on a Carver press at a 1000 pound force. The tablets prepared were studied for dissolution profile in distilled water and 0.1NHCl at 37° C. @ 50 rpm. Samples were drawn at specific time points and drug concentration was determined using a UV-spectrophotometer @271 nm, as shown in Table 6.
Tables 7-10 illustrate the foregoing formulations in 0.1N HCl as a dissolution medium. The results are illustrated in
Tables 10-13 illustrate the foregoing formulations in distilled water as a dissolution medium. The results are illustrated in
In accordance with the disclosure, an advantageous ratio of zinc acetate to sodium carboxymethylcellulose, in order to achieve maximum gel strength, is accomplished as follows.
Method: Zinc acetate and sodium carboxymethylcellulose (CMC) were weighed and mixed in a glass mortar, and 10 mL of distilled water was then added to physical mixture. Rapid gelation was observed within a few seconds. Gels were transferred to a 20 mL glass vial, and gel strength was measured on Texture Analyzer (CT3, Brookfield Engineering). A spherical probe (TA18) was attached to the shaft and was moved towards the sample at a speed of 2 mm/sec. Once it reached the trigger load of 44 mN, the probe moved to a distance of 4 mm into the gel at a speed of 0.5 mm/sec, and the load at the target was measured. Different compositions of gels were prepared and studied for their gel strength in a similar manner. The zinc/CMC ratio of 1:5 displayed the maximum gel strength in water, as shown in Table 14, and illustrated in
Once the optimal ratio of zinc acetate and sodium CMC was determined, studies were conducted to evaluate the effect of Prosolv® and solvents on gelation. Initially physical mixtures of Prosolv SMCC 90 (100 mg) and Ticalose® 6000 (250 mg) were weighed and mixed using a glass mortar with pestle. Different solvents (ultra-pure water, normal saline, hydro-alcoholic solutions and 0.1N HCl) of 10 mL volume were added to physical mixture. Gels formed were transferred to 20 mL glass vial and their strength was measured on a CT3 Texture analyzer. Same study was repeated for physical mixtures of zinc acetate (50 mg), Prosolv® SMCC 90(100 mg) and Ticalose® 6000 (250 mg), as shown in Table 15, and as illustrated in
Table 16 and
Tramadol HCl (25 mg), zinc acetate (50 mg), CMC (250 mg), and Prosolv® (75 mg) were mixed using a glass mortar and pestle. 400 mg of the mixture was weighed and then compressed on Carver press at 1000 pound force. The tablets prepared were studied for dissolution profile in distilled water and 0.1N HCl at 37° C. @ 50 rpm. Samples were drawn at specific time points and drug concentration was determined using a UV-spectrophotometer @271 nm. Results are shown in Tables 17-18, and are illustrated in
Talc:
Into 10 mL of drug solution (containing 25 mg of tramadol HCl), 50 mg of talc was added and vortexed for 5 seconds followed by centrifugation @1500 rpm for 5 minutes. The solution was filtered through a 0.2 μm syringe filter; 0.5 ml of the supernatant solution was diluted with 10 ml of solvent, and then analyzed for drug concentration by UV spectroscopy @271 nm. Results are shown in Table 19.
Zinc Acetate:
Into 10 mL of drug solution (containing 25 mg of tramadol HCl), 50 mg of zinc acetate was added and vortexed for 5 seconds followed by centrifugation @1500 rpm for 5 minutes. The solution was filtered through a 0.2 μm syringe filter; 0.5 ml of the supernatant solution was diluted with 10 ml of solvent, and then analyzed for drug concentration by UV spectroscopy @271 nm. Results are shown in Table 20.
Aluminum Hydroxide:
Into 10 mL of drug solution (containing 25 mg of tramadol HCl), 10 mg of aluminum hydroxide was added and vortexed for 5 seconds followed by centrifugation @1500 rpm for 5 minutes. The solution was filtered through a 0.2 μm syringe filter; 0.5 ml of the supernatant solution was diluted with 10 ml of solvent, and then analyzed for drug concentration by UV spectroscopy @271 nm. Results are shown in Table 21.
The following photos depict various formulations as described herein, in various solutions as indicated.
The inventive composition described above includes the following:
1. A multifunction polymer:
a. That can be added into the tablet at high concentration, provides gel strength up to 5-10 folds higher than what can be achieved with the PEO polymers while offering a similar release profile in 0.1N HCl.
b. The multifunction polymer of this disclosure is capable of binding with basic molecules such as tramadol HCl.
c. The multifunction polymer of this disclosure can provide different release profiles in water and 0.1N HCl, an almost a zero order in water, while first order in 0.1N HCl. In other words, polymers of this disclosure hardly release the drug over short term in abuse solutions (primarily in water), while offering easy release in-vivo or under in-vitro dissolution testing using 0.1N HCl.
d. The multifunction polymer of this disclosure is capable of binding to other excipients used in the tablet intended to modulate the gel strength and drug release profile.
2. A multifunction gel enhancer:
a. That strongly binds to the multifunction polymer in solution, and enhances its gelling property in respective solution.
b. That moderately binds to the multifunction polymer in solution, and modulates the drug release.
c. That partially binds to the basic active drug in solution.
3. A multifunction filler:
a. That remains non-reactive to the multifunction polymer of this disclosure; it however partially binds to the basic drug molecule in solution.
In accordance with the invention, a therapeutic crush-resistant cryogel composite with abuse-deterrent capability is formulated using Polyvinyl Alcohol (PVOH), which is a synthetic hydrophilic linear polymer produced as varied copolymer of vinyl alcohol with vinyl acetate, vinyl amine, vinyl pyrrolidone, or ethylene glycol. Due to reactive functional groups on its structure, PVOH undergoes chemical changes such as esterification and etherification, as well as physical changes such as crystallization and ion-polymer complexation. At a given molecular weight and degree of hydrolysis, the mechanical property of the final PVOH cryogel product is essentially determined by its original solution concentration, and the number of freezing and thawing cycles. Lower and higher temperature extremes and duration at which the platform is treated over specific temperature would also affect the cryogel mechanical properties to a lesser extent. The higher the concentration and the greater the number of cycles, the greater would become the cryogel mechanical property. Lower and higher extremes of mechanical properties would be undesirable due to lack of mechanical integrity and the higher PVOH concentration, respectively. However, a cryogel with optimum and desirable mechanical properties can be designed by adjusting the solution concentration and the factors influencing the cryogelation process.
When polymers are used as controlled delivery medium, their concentration in the dosage form should be kept to a minimum while offering desirable properties. Lower concentration of the polymer would minimize the polymer-drug interaction, instability of the dosage form, and facilitate its processing. PVOH cryogels generally consist of water and the PVOH polymer, and the cryogel can feasibly be made at PVOH concentration ranging 10-20 wt %. Over such range, the cryogels can become mechanically very strong like a tough rubber, which may be difficult to remove from the GI tract in that state, and disintegration of the material could be a challenge. Such concentrations can also cause excessive crystallization of the polymer, which causes instability. Moreover, it will increase the chance of unwanted interaction between the polymer and the drug, and can physically hinder the effective release of the drug from the cryogel platform.
The cryogel polymers of this disclosure would be desirable in areas where a controlled delivery vehicle with certain mechanical properties would be very advantageous. For instance, cryogels of this disclosure can be used as a vehicle for immediate or controlled release of abusable medications, whereas the vehicle possesses certain mechanical strength and viscoelastic properties that prevent the dosage form from being abused by crushing or grinding.
This invention provides a cryogel vehicle, which is manufactured at the lowest PVOH concentration yet possessing reasonable mechanical property, resembling a soft rubber. In one embodiment, a cryogel with desirable physical mechanical properties is disclosed having desirable adhesive force, adhesiveness, gumminess, and hardness making the PVOH-based delivery platform crush-resistant. At solution concentrations of about 5 wt %, a PVOH cryogel possesses tackiness, and adheres to variety of surfaces including endothelial cells. The maximum tackiness can be achieved at concentrations at around 2-3 wt % while a cryogel can still be formed. Drugs (water soluble or water-insoluble) can be dispersed into the aqueous solution of PVOH at such concentration as solid powder, solution, or dispersion. The drug-loaded mix can then undergo freezing-thawing cycle(s), by which the drug would be entrapped into the PVOH cryogel structure. Drug release would then be governed by either a diffusion mechanism if the gel is mechanically strong, or by a combined diffusion-erosion mechanism if the gel is structurally weak. A cryogel formed at such concentrations, loaded with the drug, can be housed into, for example, a soft or hard gelatin capsule for oral administration. In another embodiment, a crush resistant abuse-deterrent cryogel composite can be simply formed in any desirable shape for faster disintegration and guaranteed emptying from the stomach. This, for instance, can simply be achieved by shredding the cryogel or cryogel composite, and molding the material into desired dimensions or shapes. These cryogels can also be easily prepared in the form of a thick slab, thin film, extruded, or molded product, to suitably address the service needs.
In another embodiment, a cryogel composite containing an abuse-deterrent agent is disclosed, where drug is entrapped within its structure, and then released in a controlled manner under regular oral administration in the acidic stomach.
The PVOH cryogels of this invention possess advantages such as ease of manufacturing (one step preparation, no need for purification), ease of sterilization, simple and stable polymer structure, minimum drug-polymer interaction, absence of other chemicals or excipients, no residual processing chemicals, ease of drug loading by any form, drug loading at room temperature, and feasible processing such as molding and cutting.
Polyvinyl alcohol (PVOH) aqueous solutions were prepared by dissolving PVOH in ultrapure water at 90° C. for two hours with constant stirring. Solutions were then allowed to cool at room temperature before being used. After being cooled, a specific weight of the solution was transferred into plastic molds (dimensions 4.1×4.1×0.8 cm) and placed into a bench-top cooler (VWR Boekel Mini Fridge II 260009). The solutions were then subjected to two freeze-thaw cycles consisting of four hours of freezing at −10° C. followed by two hours of thawing at 25° C.
PVOH cryogels (5%, 8% and 10% w/w) still in their plastic molds were subjected to adhesive tests using a texture analyzer (CT3, Brookfield Engineering). Tests were performed using an acrylic probe of 12.7 mm diameter and 35 mm length (TA10) attached to the arm of the texture analyzer. The probe was lowered toward the sample until a trigger load of 67 mN was achieved. After this trigger, the probe was moved into the sample at a rate of 0.5 mm/sec to a distance of 4 mm. This was repeated for 2 cycles on each sample and a plot of load (mN) versus time (sec) was used by the instrument software (TexturePro CT) to achieve the desired parameters of adhesive force, adhesiveness, and gumminess. All tests were performed in triplicates at room temperature. Adhesive force (N or mN) is the maximum force required to pull the probe away from the sample. Adhesiveness (mJ) is the work required overcoming attractive forces between the sample and the surface of the probe. Gumminess is the energy required converting a semi-solid to a state ready to swallow. Gumminess is calculated by multiplying hardness of the substance with cohesiveness of the substance. The test apparatus is shown in
PVOH cryogels (5%, 8% and 10% w/w) still in their plastic molds were subjected to hardness testing using a texture analyzer (CT3, Brookfield Engineering). Testing was performed using Volodkevich Bite Jaws, (TA-VBJ, Brookfield Engineering) an accessory attached to the arm of the texture analyzer. The probe was lowered toward the sample until a trigger load of 67 mN was achieved. After this trigger, the probe was moved at a rate of 0.5 mm/sec to a distance of 4 mm into each sample to calculate the hardness work (mJ) done by the instrument software (TexturePro CT). All tests were performed in triplicates at room temperature. The test apparatus is shown in
Prepared PVOH cryogels (3%, 5%, 8% and 10% w/w) were trimmed into square dimensions weighing 1 gm. The square samples were then placed into 50 ml of ultrapure water at room temperature and allowed to swell freely. At specific time points, the samples were removed from the swelling medium, surface dried with a Kim Wipe, and weighed.
Table 24 and
Table 25 and
Table 26 and
Table 27 and
Table 28 and
APAP-PVOH cryogels were prepared by first making PVOH aqueous solutions in ultrapure water at a concentration of 5 and 10% w/w. After solutions were cooled to room temperature, 10 mg of acetaminophen powder (Sigma-Aldrich) per gram of PVOH solution was added under constant stirring until completely dissolved. A specific weight (2, 3.5, 5 g) of the drug loaded solution was then cast into plastic molds (dimensions 4.1×4.1×0.8 cm) and placed into a bench-top cooler (VWR Boekel Mini Fridge II 260009). The solutions were subjected to two freeze-thaw cycles consisting of four hours of freezing at −10° C. followed by two hours of thawing at 25° C.
APAP-PVOH cryogels were released from their molds and average thickness determined by digital caliper. The cryogels were then subjected to dissolution studies using a USP 2 paddle method (Distek dissolution system 2100A) in 900 ml of ultrapure water at 37.5° C. at a paddle rotational speed of 50 rpm. APAP concentration in the dissolution medium was analyzed using UV-Visible spectroscopy at 243 nm (UV-1700, Shimadzu) over time.
Tramadol-PVOH cryogels were prepared by first making a PVOH aqueous solution in ultrapure water at a concentration of 5% w/w. After the solution was cooled to room temperature, each cryogel was made by adding 20 mg of tramadol hydrochloride (Medisca, Inc.) to 2 gm of PVOH solution. Each mixture was mixed until tramadol was completely dissolved. The drug loaded solution was then cast into plastic molds (dimensions 4.1×4.1×0.8 cm) and placed into a bench-top cooler (VWR Boekel Mini Fridge II 260009). The solutions were subjected to two freeze-thaw cycles consisting of four hours of freezing at −10° C. followed by two hours of thawing at 25° C.
Tramadol-PVOH cryogels were released from their molds and subjected to dissolution studies using a USP 2 paddle method (Distek dissolution system 2100A) at a paddle rotational speed of 50 rpm. The dissolution media were 900 ml of ultrapure water, and 0.1N HCl, all at 37.5° C. Tramadol concentration in the dissolution medium was analyzed over time using UV-Visible spectroscopy at 271 nm (UV-1700, Shimadzu).
Table 29 and
Croscarmellose sodium PVOH cryogel composites were prepared by first making a PVOH aqueous solution in ultrapure water at a concentration of 5% w/w. After the solution was cooled to room temperature, 10% of croscarmellose sodium (Ac-di-Sol®) was added and uniformly mixed. The composite mixture was then cast into plastic molds (dimensions 4.1×4.1×0.8 cm) and placed into a bench-top cooler (VWR Boekel Mini Fridge II 260009). The solutions were subjected to two freeze-thaw cycles consisting of four hours of freezing at −10° C. followed by two hours of thawing at 25° C.
PVOH cryogels were released from their molds and allowed to swell in either ultrapure water, 0.1N HCl, or 40% w/v ethanol at room temperature. At different time intervals, the cryogels were removed from the swelling medium, and surface-dried using a Kim wipe before being weighed. The reported values, shown in Table 30 and
Load-Deformation measured by a bench-top comparator:
PVOH cryogels were released from their molds and allowed to swell in ultrapure water or in 0.1N HCl. Unswollen cryogels were used as a comparison. After being allowed to swell for 12 hours, the cryogels were removed from the swelling medium and surface-dried using a Kim wipe. The cryogels were then placed on the working surface of a bench-top comparator (2W, B.C.Ames). The thickness of each cryogel was measured under increasing load and the percent of deformation measured. Each test was performed on two samples at room temperature and the average reported in Table 32 and
Testing was performed using Volodkevich Bite Jaws, (TA-VBJ, Brookfield Engineering) an accessory (TA-VBJ, Brookfield Engineering) attached to the arm of the texture analyzer. The probe was lowered toward the sample until a trigger load of 67 mN was achieved. After this trigger, the probe was moved at a rate of 0.5 mm/sec to a distance of 4 mm into each sample to calculate hardness work (mJ) done by the instrument software (TexturePro CT). Results are illustrated in
Tramadol-PVOH composite cryogels were prepared by first making PVOH aqueous solution in ultrapure water at a concentration of 5% w/w. After the solution was cooled to room temperature, each cryogel was made by adding 20 mg of tramadol hydrochloride (Medisca, Inc.) to 2 gm of PVOH solution. Each solution was mixed until tramadol HCl was completely dissolved. Next, 10% of croscarmellose sodium (Ac-di-Sol®) was added and uniformly mixed. The drug loaded mixture was then cast into plastic molds (dimensions 4.1×4.1×0.8 cm), and placed into a bench-top cooler (VWR Boekel Mini Fridge II 260009). The solutions were subjected to two freeze-thaw cycles consisting of four hours of freezing at −10° C. followed by two hours of thawing at 25° C.
Drug Release from Cryogel Slab
Tramadol-PVOH composite cryogels were released from their molds and subjected to dissolution studies using a USP 2 paddle method (Distek dissolution system 2100A) in 900 ml of ultrapure water at 37.5° C. at a paddle rotational speed of 50 rpm. After 850 minutes, the dissolution medium was changed to 0.1N HCl by adding concentrated hydrochloric acid into the dissolution medium. Tramadol concentration in the dissolution medium was analyzed using UV-Visible spectroscopy at 271 nm (UV-1700, Shimadzu) over time. Results are shown in Table 33 and
Tramadol-PVOH composite cryogels were released from their molds and placed into a micro-mill grinder (Bel-Art Products) for 5 seconds. The shredded pieces were then subjected to dissolution studies using a USP 2 paddle method (Distek dissolution system 2100A) in 900 ml of ultrapure water at 37.5° C. at a paddle rotational speed of 50 rpm. After 840 minutes, the dissolution medium was changed to 0.1N HCl by adding concentrated hydrochloric acid into the dissolution medium. Tramadol concentration in the dissolution medium was analyzed using UV-Visible spectroscopy at 271 nm (UV-1700, Shimadzu) over time. Results are shown in Table 34 and
Tramadol-PVOH composite cryogels were released from their molds and subjected to dissolution studies using a USP 2 paddle method (Distek dissolution system 2100A) in 900 ml of 0.1N HCl at 37.5° C. at a paddle rotational speed of 50 rpm. Tramadol concentration in the dissolution medium was analyzed using UV-Visible spectroscopy at 271 nm (UV-1700, Shimadzu) over time. Results are shown in Table 35 and
In accordance with the invention, a deterrent cage can be formulated with an abusable medication, providing a crush-resistant platform having the ability to release its drug in a sustained manner. In another embodiment, the same platform can be used to release the drug in an immediate fashion. The deterrent cage is composed of three different polymers including a water-swellable polymer, a water-soluble polymer, and a water-insoluble polymer, that can optimally be prepared by mixing individual polymers at certain ratio, or by using pre-mixed commercially available products, as shown in Table 36.
The example formulation tested is shown in Table 36.
Extraction Studies:
Physical mixture was transferred to 20 mL glass vial. 10 mL of water was added and vortexed for 5 seconds followed by centrifugation@1500 rpm for 5 minutes. The dispersion was filtered through 0.25 μm syringe filter, and 0.5 mL of the filtrate was diluted to 10 mL. The solution was analyzed for drug concentration by UV spectroscopy @271 nm. The results are shown in Table 37 and
Drug Release Studies:
Prepared tablets were studied for their drug release profile in ultrapure water and 0.1N HCl @ 50 rpm and 37±2° C. (USP II). Samples were pulled at different time points and the % drug released was plotted versus time. The first 5 hours, the release was studied in ultrapure water, and then the medium was changed to 0.1N HCl by adding concentrated HCl. The results are shown in Table 38 and
The formulation is composed of only one deterrent agent (croscarmellose, Ac-di-Sol®). Trapping capacity of this formulation is 69%, 22%, 67%, 77% in water, saline, EtOH40%, and pH 3 medium respectively. Such composition can release about 92% of its contents in 0.1N HCl providing an immediate release profile.
Formulation:
The formulation tested is shown in Table 39.
Preparation of Tablets:
Each ingredient was weighed and added to glass mortar where they were mixed by geometric dilution. Physical mixture was transferred to tablet press and compressed@2000 pounds force.
Extraction Studies:
Physical mixture was transferred to 20 mL glass vial. 10 mL of water was added and vortexed for 5 seconds followed by centrifugation@1500 rpm for 5 minutes. As can be seen in
Drug Release Studies:
Prepared tablets were studied for their drug release profile in ultrapure water and 0.1N HCl @ 50 rpm and 37±2° C. Samples were pulled at different time points and graphs were plotted with % drug released vs time. Results are shown in Table 40 and
The sustained release formulation in trial 1 is composed of Ticalose® 6000 as a viscosifying agent. This composition provides a sustained release profile with different release profiles in water and in 0.1N HCl. As shown in the graph (
The formulation tested is shown in Table 41.
Preparation of tablets: Each ingredient was weighed and added to glass mortar where they were mixed by geometric dilution. Physical mixture was transferred to a tablet press and compressed @2000 pounds force. Results are shown in Tables 42 and 43, and
The formulation in trial 2 is composed of Ticalose® 6000 as a viscosifier and Kollidon® SR as a plastic agent providing crush resistance when heated at 120° C. for 1 hr.
Formulation:
The example formulation tested is shown in Table 44.
Preparation of Tablets:
Each ingredient was weighed and added to a glass mortar where they were mixed by geometric dilution. Physical mixture was transferred to tablet press and compressed @2000 pounds force. Results are shown in Tables 45 and 46, and
The formulation in trial 3 is composed of Ticalose® 6000 as a viscosifier and Kollidon® SR as a plastic agent at higher concentration of Kollidon® SR providing crush resistance when heated at 120° C. for 1 hr. Addition of more SR into composition reduces the ultimate amount of release from (93-100%) down to (78-88%) in 0.1N HCl. The heated tablet provides more hindrance to release.
Formulation (Trial 1):
The formulation tested is shown in Table 47.
Preparation of Tablets:
Each ingredient was weighed and added to glass mortar where they were mixed by geometric dilution. Physical mixture was transferred to tablet press and compressed @2000 pounds force. Results are shown in Tables 48-49 and
Regular tablets (non-heated) provide immediate but hindered release in water up to 50%, whereas the same formulation in 0.1N HCl releases almost all its contents in an immediate fashion. Contrary to other compositions containing Kollidon® SR with sustained release property, the composition containing Kollidon® SR and a superdisintegrant provides immediate release in both water and 0.1N HCl if not heat-treated.
As opposed to non-heated tablets which provided immediate release profile, same heated tablets containing Kollidon® SR and superdisintegrant provided a 24 hr sustained release in 0.1N HCl. Same composition displayed a hindered sustained release of maximum 44% in water. The amount of drug release from same heated composition in pH 3 medium was reached to 87%.
Tablet Crusher
Tablets prepared as in Trial 1 (immediate and sustained release) were tested using a regular tablet crusher. Composition containing 30% of Ac-di-Sol® and 50% of Kollidon® SR displayed different resistance to crushing when tested in a tablet crusher. As can be seen in
Tablets were heat treated for 1 h@120° C. Non-treated and heat treated tablets of a same composition were then placed in a heavy-duty grinder (MicroMill®II by Science Ware) for 10 sec. Crushed tablets were collected and characterized for particle size distribution. Sieve analysis was carried out by placing sieves (#20, 35, 60, 120, 325 and bottom) on sifter (SS-3CP by Cole Palmer). Tapping was done for one minute at 60 taps per minute. Results are shown in
The formulation tested is shown in Table 50 and results are shown in
The formulation tested is shown in Table 51 and results are shown in
The formulation tested is shown in Table 52 and results are shown in
Relative particle size is shown in
Effect of Deterrent Concentration on Tramadol Release from Deterrent Cage
Regular Tramadol Tablets with No Heat-Treatment
The formulation tested is shown in Table 52, tested in water, as shown in Table 54, and in HCl, as shown in Table 55.
As can be seen in
As can be seen in
As can be seen in
As can be seen in
Release data for heat-treated tramadol tablets in water are shown in Table 56, and for HCl in Table 57.
As can be seen in
As can be seen in
As can be seen in
As can be seen in
Crush Resistance of the Deterrent Cage (Immediate and Sustained Release Trial 1) by Ball Mill
The formulation tested is shown in Table 59.
Tablet preparation: Ingredients were mixed in glass mortar with pestle and compressed on Carver press @ 2000 pounds force. The prepared tablets were heat treated @120° C. for 1 hour.
Crushing tablets using ball-mill: Both heat treated and regular tablets were crushed using a ball-mill for 5 minutes at a frequency of 25 Hz. In this test, the configuration included a Retsch Mixer mill MM200, # of balls 2, ball diameter 10 mm, with both balls and the mill container made of stainless steel, as shown in
Polyethylene oxide (PEO) is the most common polymer used in the preparation of Nucynta® ER, reformulated OxyContin, reformulated Opana® ER, as well as a number of other abuse-deterrent formulations. Some formulations benefit from its solution properties while others benefit from both of the solution and solid properties of PEO. Major advantages of this polymer is its low melting point in solid state, and high viscosity build up in solution state. Moreover, the polymer is non-toxic, can be used at high concentration, and has least interactions with the active within the formulation. Due to its excellent film forming capability at low temperatures, and ability to build high viscosity in water and hydroalcoholic solutions, this polymer can provide crush and extraction resistance in solid and solution states respectively. Out of different grades, the high molecular weight PEOs have practically been used to achieve crush and extraction resistance as PEOs at higher molecular weight (POLYOX™ Coagulant) can provide superior mechanical properties and solution viscosity. On the other hand, the polymer has certain weaknesses, in particular in its solution state. The solutions of PEO are extremely sensitive to boiling temperatures, high shear rates (rate of mixing), and salts. In other words, the high viscosity built up by PEO in water or hydroalcoholic solutions would be significantly lost if the temperature of the PEO solution is brought up to high temperatures, agitated at high speed, and mixed with salts.
Various deterrent agents capable of binding, absorbing, and adsorbing a basic drug such as Tramadol HCl are described. However, the deterrence efficiency of some deterrents can be sensitive to the medium that abusers use to extract the drug, and this is attributed to the mechanism by which these deterrents function. Those based on organics (such as crosslinked carboxymethylcellulose) are more effective at low ion and alcohol concentrations due to their purely anionic structure. Moreover, their degree of carboxyl substitution can significantly affect the deterrence capacity of this deterrent. Those based on inorganics (such as bentonite clay) tend to bind to the drug effectively even in the presence of 0.1N HCl. Others functioning via adsorption mechanism (such as charcoal) are sensitive to the presence of alcohol while they can provide excellent binding even in the presence of hydrochloric acid. Abusers, in practice, utilize any effective liquid, individually or in combination, to maximize the yield of drug extraction. Therefore, a deterrent blend or composition is envisioned within the disclosure in order to maximize the deterrence capacity when two or more of these extracting medium (water, alcohol, salt, juices, etc.) are used.
The instant invention offers a very effective formulation strategy to provide crush and extraction resistance to abusable medications. Methods to achieve effective crush resistance properties of PEO together with extraction resistance of the deterrent agents are discussed. It is shown that it's not necessary to use a high molecular weight PEO to achieve crush resistance; in fact the data shows that even the lowest molecular weight PEO grade (100K, Sigma Aldrich) could provide a level of crush resistance similar to that of the highest molecular weight PEO grade (Polyox™ WSR 303). This is primarily due to lower film forming temperature of the lower grades which enhances the adhesiveness and hence the integrity of the tablet composition. The lower film forming temperature of the lower grades also means that the tablets containing PEO can thermally be processed at lower temperature or for shorter period of time at higher temperatures, reducing the risk of drug degradation or interaction with other excipients. The instant invention discloses a tablet composition containing tramadol HCl, lower molecular weight PEOs, and crosslinked carboxymethylcellulose (AcDiSol®) at 1/1 weight ratio, heat treated at temperatures lower than 100° C. for 1 hr. Such composition can provide two completely different release profiles in water and in 0.1N HCl. In other words, contrary to compositions containing PEO providing almost same extended release profiles in both solutions, this composition displays very limited release in water and completed release in 0.1N HCl.
Moreover, such composition is extremely resistant to mechanical crushing utilizing pill crusher, ball mill (at different frequency and time), and grind mill.
Immediate Release Formulations with No Crush Resistance Feature Containing a Deterrent Agent
The deterrence capacity of a composition containing high amounts of crosslinked carboxymethyl cellulose has previously been reported. In consideration of this, a test formula is provided in Table 62.
Extraction studies: The physical mixture was transferred to 20 mL glass vial. 10 mL of solvent was added and vortexed for 5 seconds followed by centrifugation@1500 rpm for 5 minutes. The dispersion was filtered through 0.25 μm syringe filter, and 0.5 mL of the filtrate was diluted to 10 mL. The solution was analyzed for drug concentration by UV spectroscopy @271 nm. Results are shown in
Drug Release Studies: Prepared tablets were studied for their drug release in ultrapure water and 0.1N HCl @ 50 rpm and 37±20 C (USP II). Samples were pulled at different time points and the % drug released was plotted versus time. The first 5 hours, the release was studied in ultrapure water, and then the medium was changed to 0.1N HCl by adding concentrated HCl. Results are illustrated in
The formulation is composed of only one deterrent agent (Ac-di-Sol®). Trapping capacity of this formulation is 69%, 22%, 67%, 77% in water, saline, EtOH40%, and pH 3 medium, respectively. Such composition can release about 92% of its contents in 0.1N HCl providing an immediate release profile. However, this formulation is not resistant to any mechanical forces and simply grinds into powder.
Heat Treatment
The following examples show how binding property of polyethylene oxide can be utilized in preparation of crush resistant compositions containing a deterrent agent. The tablets containing PEO were heat treated at different temperatures.
Formulation: Tramadol HCl (100 mg), AcDiSol® (250 mg) and PEO WSR Coagulant (150 mg). Tablets were prepared by mixing the ingredients in a glass pestle and mortar, compressed at 20001b force on a Carver press. Data are shown in Tables 63-68.
Regular Tablets Undergone No Heat Treatment
Tablets Undergone Heat Treatment at 65° C./1 hr
Tablets Undergone Heat Treatment at 120° C./1 hr:
Ball Mill Studies:
Tablets were crushed using a ball mill (Retsch Mixer Mill MM200). Two steel balls (1 cm in diameter) were used at frequency of 25/sec for 5 minutes. The crushed powder was transferred to sieves and particle size distribution was determined. Sieves were placed in a column by their sieve number (20, 35, 60, 120 and 325) and receiver at the bottom. Top sieve was loaded with the sample and sieves were placed on a sifter (Sieve sifter SS-3CP by Cole Parmer). Tapping was run for one minute @ 60 tapping per minute. Particles retained on each sieve were separated and weighed.
With reference to
After ball milling for 5 min, same tablets were treated in a grind mill for 10 sec. Compositions containing 0/500, 100/400, 150/350, 200/300, and 250/250 completely resisted the grind milling.
DSC Studies:
Different grades of PEO were weighed and transferred to aluminum pans and sealed hermetically. The first heating cycle was as follows: 1 min at 25° C., heating the sample to 150° C. @ 10° C./min, held for one min at 150° C., and cooled back to 25° C. The first cycle was conducted to erase the thermal history. Second cycle was performed similar to the first cycle to obtain actual softening or melting data.
The first cycle is illustrated in
With reference to
At A/PEO ratio of 1, the effect of PEO molecular weight on crush resistance was studied, as shown in Tables 71.
Tablet preparation: 250 mg of AcDiSol® and 250 mg of each PEO grade were mixed in a pestle and mortar, compressed into tablet at 2000 lb on a Carver press, and then heated at 120° C. for 1 hr.
With both ball mill and grind mill studies, the PEOs of different grades predominantly produce particles larger than 850 μm (retained on sieve #20). With reference to
Since PEO205 was found to be as effective as high molecular weight PEOs including PEO coagulant and 303, we performed additional studies on tablets composed of 50% AcDiSol® and 50% PEO205, to evaluate the effect of curing temperature on crush resistance. The the graphs in
Tablet composition: Tramadol HCl (25 mg), AcDiSol® (250 mg) and PEO 205 (250 mg). Tablets were prepared by mixing the ingredients in a glass pestle and mortar. Physical mixture was compressed at 2000 lb pressure on a Carver press, and then heat treated at 90° C. for 1 hr. Results are shown in Tables 72 and 73.
Drug Release Studies
As shown in
Crush Resistance Studies
Untreated and heat-treated tablets were processed using a ball mill for 5 min, and then with a grind mill for 10 sec, with results illustrated in
Pill Crusher Study
Ball Mill Study
Grind Mill Study
A release study of a PEO (100K)-based tablet is shown in Tables 74-75, and is illustrated in
Results of a crush resistance study using a ball mill and a grind mill are illustrated in
Tablet preparation: Physical mixture of 25 mg tramadol HCl, 250 mg PEO (coagulant and PEO 100K) and 250 mg AcDiSol® compressed into tablet at 2000 lb force using a Carver press. Some tablets were also heat treated at 90° C. for 1 hr (NH for no heat treatment and H for heated in the following graphs).
Grind mill studies: Both non treated and heat treated tablets were crushed in a grind mill for 30, 60 and 120 sec, and particle size distribution was determined using sieve analysis, with results illustrated in
Pill Crusher Study
Ball Mill Study
Grind Mill Study
Tables 76 and 77 show release data for tablets based on PEO 100K, as illustrated in
An abuse-deterrent cage of the invention is composed of a water-swellable polymer that relatively grows or expands in size when exposed to an aqueous medium. It also effectively binds to the active cationic ingredient such as pain medications carrying positive charges in their structure. The drug binding to the water swellable component of the cage is pH sensitive; in other words the binding is effective at normal pHs; however, it becomes ineffective at physiological pHs close to 1. The cage also includes a water-insoluble hydrophobic polymer that possesses a relatively low glass transition temperature preferably ranging 25-60° C. and advantageously ranging between 27 and 40° C. When tablet containing the drug, the water swellable polymer and the hydrophilic polymer is heated above the glass transition temperature of the hydrophobic component of the cage, the tablet becomes integrated or sintered into one strong body that can resist abuse by crushing and extraction. Elsewhere herein it is disclosed that if the tablet is heat treated at 120° C. for 1 hour, its mechanical strength would be sufficiently high to resist ball milling and heavy duty grind milling. For instance, if such tablet is processed in a ball mill (having 2 steel balls each 10 mm in diameter) at a frequency of 25/min for 5 min, the tablet generally stays intact or generates over 80% of large particles (greater than 250 μm). This disclosure relates to using sintering enhancers to lower the temperature at which the tablet is sintered into one integrated piece with sufficient mechanical strength against abuse forces. The disclosure includes the use of Carbowax™ (polyethylene glycol 8000) in combination with a water-swellable binding polymer (AcDiSol®) and a hydrophobic polymer (Kollidon® SR). The tablet is heat treated at generally lower temperature than what was previously reported. According to this invention, a 500 mg tablet composition containing 100 mg of tramadol HCl, 250 mg of Kollidon® SR, 150 mg of Ac-Di-Sol® and 25 mg of PEG8000, heat-treated at 90° C. for 1 hr can offer improved resistance to abuse by crushing and extraction.
A plasticizer has been incorporated into the formulation in accordance with Table 78.
Preparation of Tablets:
Individual excipient was weighed and mixed in a glass mortar. The physical mixture was transferred to Carver press and compressed @ 2000 pound force. Prepared tablets were heat treated @120° C. for 1 hour. Heat treated tablets were evaluated for their crush resistance.
Ball Mill Method:
Each tablet was weighed and transferred to a stainless steel container, and ball milled using two stainless steel balls (10 mm in diameter) at a frequency of 25/sec for 5 minutes.
Sieve Analysis:
Sieves were placed in a column by their sieve number (20, 35, 60, 120 and 325) and the receiver was placed at the bottom. Top sieve was loaded with the sample and sieves were placed on a sifter (Sieve sifter SS-3CP by Cole Parmer). Tapping was performed for one minute @ 60 tapping per minute. Particles retained on each sieve were separated and weighed according to the formula % retained on sieve# ((powder retained on sieve #/total powder weight)*100), with results shown in Table 79 and
All heat-treated tablets were ball-milled under similar conditions, and resisted crushing and generated only large particles under crushing forces. There is a slight effect on crush resistance as PEG concentration increases, however the effect reaches plateau at 25 mg concentration, as shown in Table 80 and
Since there is no difference in particle size distribution of the 25 mg and the 50 mg heat-treated compositions when processed via ball milling for 5 minutes, the 25 mg heated composition was evaluated for further testing, ball milling for longer period of time, and the use of a heavy duty crusher (grind milling).
Ball Mill Method:
Each tablet was weighed and transferred to a stainless steel container with two stainless steel balls (10 mm in diameter). The milling was performed for 15, 30 and 45 minutes at the frequency of 25/sec.
Grind Mill Method:
Tablets, after the ball mill experiment, were transferred to a heavy-duty grinder and processed for 10 sec. The ground tablets were analyzed for particle size distribution by sieve analysis.
Sieve Analysis:
Sieves were placed in a column by their sieve number (20, 35, 60, 120 and 325) and the receiver at the bottom. Top sieve was loaded with the sample and sieves were placed on a sifter (Sieve sifter SS-3CP by Cole Parmer). Tapping was performed for one minute @ 60 tapping per minute. Particles retained on each sieve were separated and weighed.
% retained on sieve #: (powder retained on sieve #/total powder weight)*100
Results are shown in Table 82 and
Control Tablet with No PEG:
Heat-Treated Control Tablets with No PEG:
Ball mill duration did not affect particle size distribution, and hence tablets remained crush resistant. Results are shown in Table 83 and
Heat-treated control tablets with no PEG show almost no difference in resistance to grind milling with milling duration. However, comparison of the two graphs shows that grind milling is much more effective than ball milling in crushing the tablets into finer particles.
As can be seen in Table 84 and
As can be seen in Table 85 and
Control tablets with no PEG collectively (over total milling duration) resist ball milling, however when crushed using grind milling, 30% more of finer particles were generated, as shown in
Plasticized tablets containing 25 mg PEG 8000 collectively resist ball milling to full extent of 100%, however they showed relatively less resistance to grind milling as 16% finer particles were generated during the process. The effect of crushing process was shown to be significant. Tablets containing 25 mg of PEG 8000 generate 14% less finer particles, as shown in
When processed through ball milling, control and plasticized tablets both showed almost same crush resistance. In other words, for plasticized tablets, the effect of crushing process (ball versus grind milling) is much less compared to tablets with no plasticizer, as shown in
When processed through grind milling, control tablets with no plasticizer showed significantly less resistance to crushing compared to plasticized tablets, as shown in
The plasticized formulation is shown in Table 86, and the results are shown in Table 87 and
Tablets ball-milled at 15, 30, and 45 min, processed in a grind mill for 10 sec. Results are shown in Table 88, and in
The plasticized formulation is shown in Table 89, and the results are shown in Table 90 and
Tablets ball-milled for 15, 30, and 45 min, processed in a grind mill for 10 sec. Results are shown in Table 91, and are illustrated in
Table 92 and
All data for the tablets which have undergone different heat treatments at different grinding times are shown in
Control and plasticized tablets (with 25 mg PEG8000) to be heat treated are formulated as in Table 93, with release results for no heat-treatment shown in Table 94 and
It has previously been disclosed, for example in U.S. Patent No. 61/918,880, which is incorporated herein by reference in its entirety, that the addition of bentonite clay into a tablet dosage form containing tramadol HCl will significantly reduce the amount of available drug if the dosage form is tampered. Bentonite clay can directly be added into a solid dosage form containing the controlled substance drug tramadol HCl. Alternatively, the drug can be formulated into a complex with the clay before being formulated into a final dosage form. This drug-clay complex will not readily release drug if an abuser were to sniff the powder from crushed tablets as compared to free drug. Moreover, the clay itself is irritating in powder form; as would occur when tablets are crushed into fine particles. In the case where free clay particles are incorporated into a dosage form, the clay will immediately form a strong complex with the basic drug in solution, preventing the abusable drug from being extracted into solution. The following graph shows the powerful binding effect of bentonite clay with tramadol HCl.
With reference to
For extraction/injection purposes, abusers are likely to disperse crushed tablet(s) in an aqueous medium (<10 mL in volume), then filter the medium to obtain a clear solution for injection. It is known that bentonite particles can strongly bind to tramadol HCl molecules in an aqueous medium, and the objective of this disclosure is to enhance this effect by reducing filtrate volume (volume passing through filter), enhancing binding capacity through molecular entrapment and coagulation, and preventing drug extraction from an aqueous dispersion. This disclosure discloses that 1) addition of a minute amount of very high molecular weight polyethylene oxide (PEO) in solid state can induce coagulation (as shown below) in a dispersion system composed of tramadol HCl and bentonite clay. As shown herein, a tablet formulation containing tramadol HCl, bentonite clay, and minute amounts of a PEO polymer possesses better deterrence capacity than control tablet without PEO. Compared to control tablets containing drug and bentonite clay, new tablets containing addition of PEO can enhance the deterrent capacity by about 4-5% due to molecular entrapment of the drug and 8-10% by reducing the filtrate volume. The new tablets also display aversive properties once in solution; and addition of sodium bentonite to a pharmaceutical compositions containing an abusable medication can enhance drug binding and prevent drug extraction due to its binding and dispersion stability.
Experimental:
A drug stock solution containing tramadol HCl in deionized water (2.5 mg/mL) was prepared. Different amounts of the bentonite clay were added into 20 mL scintillation vials, to which 10 mL of the drug solution was added. The dispersion was mixed by vortexing for 5 seconds followed by centrifugation at 1500 rpm for 5 minutes. The supernatant was then extracted and filtered through a 0.2 micron syringe filter. Concentration of drug remaining in this filtered extract was then measured by UV-Visible spectroscopy at 271 nm (Shimadzu UV-1700 spectrophotometer).
Sample Preparation:
Control: 0.5 mL of drug solution (2.5 mg/mL) was diluted to 10 mL with DI water to measure drug binding.
Non-coagulated suspension: To three different glass vials containing 10 mL of drug solution (2.5 mg/mL) was added 50 mg, 75 mg and 100 mg of bentonite. The suspensions were then centrifuged for 5 min at 1500 rpm and the supernatants were filtered. A 0.5 mL of filtered supernatants were diluted to 10 mL with DI water to measure drug binding.
Coagulated suspension: To three different glass vials containing 10 mL of drug solution (2.5 mg/mL) was added 50 mg, 75 mg and 100 mg of bentonite, and then 2 mg of polyethylene oxide (PEO). The dispersions were centrifuged for 5 min at 1500 rpm. The 0.5 mL of filtered supernatants were diluted to 10 mL with DI water to measure drug binding.
The amount of drug bound (%) to clay particles for the control, non-coagulated, and coagulated dispersion systems are shown in Table 97, and are illustrated in
Starting with 10 mL of an initial drug solution, the filtrate recoverable after clay flocculation was determined volumetrically. As shown in
With reference to
Suspension behavior of different sodium bentonite samples after centrifugation at 1500 RPM for 5 min compared with that of calcium bentonite suspension is described below. Sodium bentonite prepared using 40-50% sodium carbonate displayed maximum stability.
The main characteristic differences observed between sodium bentonite and its calcium form are shown in the Table 98.
Experimental: A 200 mg of calcium bentonite (Sigma) and sodium bentonite (Alfa Aesar) were dispersed in 10 mL of ultrapure deionized water. The suspension was then filtered under negative vacuum pressure of 200 mmHg through a filter membrane (tea bag). A 20 mL of ultrapure deionized water was passed through the filter after each experiment to clean the filter. For each experiment, the amount of time needed for the dispersion to pass through the filter was recorded, as illustrated in
Bentonite retention on filter membrane (tea bag) after vacuum filtration can be visualized in
Suspension stability of sodium and calcium bentonite clays have been examined under normal gravity for 12 hours. Sodium bentonite remained well suspended while calcium clay settled as shown in Table 99.
Thermogravimetric analysis was used to determine the amount of moisture in different bentonite clays, as shown in Table 101, and as illustrated in
Binding with Diphenhydramine:
Drug solutions (at different concentrations) were prepared by dissolving the desired amount of diphenhydramine HCl in 200 mL DI water. A 25 mg of desiccated clay sample was added to 10 mL of this solution in a centrifuge tube. The suspension was vortex-mixed for 30 sec., centrifuged at 2500 RPM for 5 min, and the supernatant was filtered through a 0.2 micron filter. A control solution with no clay content was prepared for each drug concentration, and the absorbance of all solutions was determined by UV spectrophotometer at 258 nm.
Table 106 and
Flocculation behavior of two bentonite samples was studied by adding 2 mg of PEO to 10 mL of the suspension containing 25 mg clay, as shown in Table 111.
Particle Size of the Clays Used in this Study:
With reference to
200 mg of Croscarmellose sodium was added to 10 ml solution of 25 mg of Dextromethorphan HBr in water. Mixture was thoroughly mixed by vortexing for 30 seconds, and centrifuged @1500 rpm for 5 minutes. Supernatant solution was separated from the complex and washed with deionized water three times. Washings were collected and drug concentration (UV absorption at 276 nm) was determined in both supernatant and washings, per Tables 113 and 114.
In a 20 ml scintillating vial containing 10 ml of 0.1N HCl, 200 mg of the complex was added. Solution was vortexed and centrifuged@1500 rpm for 5 minutes. Supernatant solution was separated and drug concentration was determined at λmax of 276 nm, per Table 115.
This data shows that 200 mg of sodium croscarmellose can bind to about 18 mg of dextromethorphan HBr.
10 g of Croscarmellose sodium was added to 500 ml drug solution (2.5 mg/ml). Complex prepared was centrifuged and separated. Prepared complex was washed under vacuum three times with deionized water and dried in a hot air oven @65° C. Dried complex was crushed into fine powder in a ball mill and passed through sieve #60(250 microns). Powdered complex was further used for preparation of tablets, and the physical blend was used as control.
All ingredients were weighed and mixed in a glass mortar and pestle. 500 mg of mixture was transferred to carver press and compressed into a tablet @2000 lb load force. Prepared tablets were studied for their drug release profiles and extraction studies.
200 mg of the complex was added to different extraction solvents including 0.1N hydrochloric acid (0.1N HCl), pH3 solution, normal saline, 40% ethanol-water solution (40% EtOH), 60% ethanol-water solution (60% EtOH), and pure ethanol (100% EtOH). The solution was vortex mixed and left standing for 15 min to reach equilibrium extraction. A physical blend of CCS and DEX (8:1 weight ratio similar to the complex) was also subjected to extraction in above solvents. Both the complex and physical blend solutions were centrifuged @1500 rpm for 5 min, and the supernatants were analyzed by UV spectrophotometry @276 nm to determine the amount of drug extracted into the solvents. 1 mL of the supernatant was diluted 10 times in the corresponding solvent. Table 118 shows the amount of DEX extracted and % extraction in different solvents for physical blend and complex.
The following experiments show that the yield of complexation increases as drug concentration in solution increases.
Croscarmellose—DEX Complexes were prepared at ratios of 8:1 (200 mg of CCS and 25 mg DEX), 2:1 (200 mg CCS and 100 mg DEX), 1.4:1 (200 mg CCS and 140 mg DEX), and 1:1 (140 mg CCS and 140 mg DEX). Complexes were washed with DI water three times and dried at 65° C. for 4 hours. The dried complexes were crushed into fine particles using ball mill and passed through 60 # sieve. To compare complexation or entrapment efficiency of these complexes, a fixed weight of the complex was added to 0.1N HCl. For 8:1, 2:1, and 1.4:1 ratios, 200 mg of complex was added to 10 mL of 0.1N HCl and 150 mg of complex was added to 10 mL of 0.1 N HCl for the 1:1 ratio. The solution was vortex mixed and left standing for 15 min to reach equilibrium extraction. After 15 min, solutions were centrifuged @1500 rpm for 5 min and supernatants were collected and analyzed by UV spectrophotometer @276 nm. Table 119 and
Blend: 500 mg of croscarmellose sodium and 25 mg of DEX were weighed and added to 300 ml of different solvents (water, pH3 and 0.1N HCl). Samples were pulled at different time points (5, 15 and 30 min) and their drug concentrations were determined using UV. Similar procedure was repeated for 2500 mg of croscarmellose sodium and 125 mg of drug (5 times the initial amounts).
Complex: Complex equivalent to 125 mg (five doses) of DEX was weighed and added to 300 ml of different solvents including water, pH3 solution, and 0.1 N HCl, under magnetic stirring. Samples were pulled at 5, 15 and 30 min form each solvent, and then analyzed for drug content using UV spectrophotometer @ 276 nm. Percentage of drug released was calculated using standard curve equations in each solvent, as shown in Table 120.
All ingredients were weighed and mixed in a glass mortar and pestle. 500 mg of mixture was transferred to carver press and compressed into a tablet @2000 lb load force. Prepared tablets were studied for their drug release profiles and crush resistance studies, as shown in Table 122 and
In
Table 124 shows that 22.8 mg (100% added as complex) is being released in 0.1N HCl.
In conclusion, the invention exemplifies a variety of compositions useful for inhibiting and/or preventing the isolation and concentration of drug constituents for misuse. These compositions are anticipated to reduce the incidence of tampering and abuse of pharmaceutical products and alcohol worldwide.
All patents and publications mentioned in this specification are indicative of the levels of those skilled in the art to which the disclosure pertains. All patents and publications are herein incorporated by reference to the same extent as if each individual publication was specifically and individually indicated to be incorporated by reference. It is to be understood that while a certain form of the disclosure is illustrated, it is not intended to be limited to the specific form or arrangement herein described and shown. It will be apparent to those skilled in the art that various changes may be made without departing from the scope of the disclosure and the disclosure is not to be considered limited to what is shown and described in the specification. One skilled in the art will readily appreciate that the present disclosure is well adapted to carry out the objectives and obtain the ends and advantages mentioned, as well as those inherent therein. The compositions, pharmaceutical compositions, methods, procedures, and techniques described herein are presently representative of the preferred embodiments, are intended to be exemplary and are not intended as limitations on the scope. Changes therein and other uses will occur to those skilled in the art which are encompassed within the disclosure. Although the disclosure has been described in connection with specific, preferred embodiments, it should be understood that the disclosure as ultimately claimed should not be unduly limited to such specific embodiments. Indeed various modifications of the described modes for carrying out the disclosure which are obvious to those skilled in the art are intended to be within the scope of the disclosure.
In addition, unless mention was made above to the contrary, it should be noted that all of the accompanying drawings are not to scale. There are many different features to the present invention and it is contemplated that these features may be used together or separately. Thus, the disclosure should not be limited to any particular combination of features or to a particular application of the disclosure. Further, it should be understood that variations and modifications might occur to those skilled in the art to which the disclosure pertains. Accordingly, all expedient modifications readily attainable by one versed in the art from the disclosure set forth herein are to be included as further embodiments of the present invention.
This application claims the benefit of priority to U.S. Provisional Patent Application No. 62/244,637, filed on Oct. 21, 2015, the content of which is hereby incorporated by reference in its entirety.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US16/58097 | 10/21/2016 | WO | 00 |
| Number | Date | Country | |
|---|---|---|---|
| 62244637 | Oct 2015 | US |
