1. Field of the Invention
This invention relates to treatment of cervical intraepithelial neoplasia including the administration of a chemexfoliating agent; and more particularly, to compositions and therapeutic films for delivering pharmaceutically active epithelial exfoliating reagents to the cervix. In particular, the films can also be used to deliver alpha-hydroxy acids (AHA), and/or trichloroacetic acid (TCA) as a chemical exfoliant for treatment of cervical intraepithelial neoplasia (CIN) 1, 2, and 3. Further, this invention relates to devices for using the therapeutic films, and combinations of films and devices which facilitate the use of these films.
2. Description of the Related Art
Cervical cancer was the third most commonly diagnosed cancer in women in 2008, with an estimated 529,800 new cases worldwide, more than 85% of which were in developing countries.
The current method for diagnosing cervical cancer is colposcopy in which acetic acid is used as a staining agent to visualize abnormal tissue. Meanwhile, current management of patients with cervical intraepithelial neoplasia (CIN) includes the following treatments: Loop Electrical Excision Procedure (LEEP), Cold Knife Conization (CKC), cryosurgery, laser ablation, or hysterectomy. These procedures lead to partial destruction of the cervix. At the very least, the destruction will render the patient's future colposcopies unsatisfactory, because the physician will be unable to clearly visualize the squamo-columnar junction due to scarring. A more serious side effect is cervical incompetence, which poses the most impact to women of reproductive age who are still planning to have children. This destruction is of most concern for patients with recurrent disease, because additional treatments on a shorter cervix are more challenging surgically.
Despite its long history as a diagnostic procedure, colposcopy continues to have varying success. In conjunction with acetic acid, the sensitivity of colposcopy to distinguish normal from abnormal tissue is relatively high. The accuracy, however, to distinguish low-grade lesions from high-grade lesions and cancer remains low. Additionally, a substantial proportion of high-grade lesions may fail to be identified at colposcopy, resulting in no treatment and subsequent further neoplasia. In a post hoc analysis of more than 47,000 women, approximately 20% additional CIN 2 or worse and CIN 3 or worse was identified in women who did not have a visible lesion on colposcopy. Therefore the treatment of CIN I may be just as important as treating CIN II or III. However, the current above methods for removing CIN 1 abnormal tissue is traumatic, and consequently non-prescribed, largely due to the lack of a simple, non-invasive, and inexpensive procedure.
Therapeutic compositions for treatment of cervical intraepithelial neoplasia include a chemexfoliating agent, including for example, trichloroacetic acid (TCA).
In some embodiments, physiologically acceptable films for the delivery of pharmaceutically active reagents for the treatment of cervical intraepithelial neoplasia in women (CIN 1, 2, 3) include suspensions of chemical epithelial exfoliating agents in a topical film having at least one dissolvable treatment layer. The dissolvable treatment layer immediately begins to dissolve upon contact with the moist epithelial tissue of the cervix. Suspended or dissolved agents in the dissolved film will then interact with the epithelial layer in contact with the treatment layer. In one embodiment, a therapeutic concentration of trichloroacetic acid (TCA) is dissolved or suspended in the dissolvable film, and is quickly released as the dissolvable film ablates. In another embodiment, alpha-hydroxy acids may be used as the exfoliating reagent.
Another embodiment includes a capping layer of either a non-dissolving or relatively slower dissolvable film cap, or cup, enclosing the treatment layer on the top and, optionally, on the perimeter sides of the therapeutic patch. The capping layer serves to isolate the treatment layer to just the epithelial tissue immediately underneath the treatment layer to thus prevent the TCA from migrating outside of the perimeter of the therapeutic patch which may result in possible irritation of adjacent vaginal epithelium. The capping layer's rate of dissolving is calculated to provide containment protection for at least as long as the treatment layer is still chemically active.
In one embodiment, a neutralizing reagent is provided in the capping layer to neutralize any remaining TCA or AHA after ablation of the treatment layer. When the capping is exposed to the released TCA in the ablated treatment layer, it may activate or react with an appropriate halochromic chemical compound as a pH indicator to permit visual indication and verification of final consumption of the exfoliating reagent and the end of the physiological activity. In order to ensure total consumption of the TCA or AHA, a neutralizing agent may be incorporated in the capping layer as well, or in an intermediate neutralizing layer. The neutralizing layer is disposed intermediate of the treatment layer and the capping layer. The neutralizing agent is released during the ablation of the neutralizing layer, and after the ablation of the treatment layer, to ensure neutralization of the TCA or AHA, the neutralizing agent being provided in a concentration sufficient to neutralize an anticipated amount of TCA or AHA residual.
In another embodiment, the capping layer or the neutralizing layer may also contain allantoin to provide a moisturizing and keratolytic effect, increasing the water content of the extracellular matrix and enhancing the desquamation of upper layers of dead skin cells resulting from the physiological activity of the TCA or AHA. Also, the allantoin will increase the smoothness of the replacement epithelial skin layer, promote cell proliferation and wound healing; and provide a soothing, anti-irritant, and skin protectant effect by forming complexes with any remaining reagents. The allantoin is released upon ablation of the neutralizing layer, or the capping layer. In an embodiment where the capping layer is not-dissolvable, the allantoin may be made available by leaching the allantoin from a porous capping layer matrix.
In yet another embodiment of the therapeutic patch of this invention, the capping layer may be a non-dissolving layer that includes an inside surface that when adjacent to the dead epithelial cells, will have a mechanical or chemical attachment system for attaching to the dead cells and allowing easy removal of the dead cells upon extraction of the undissolved capping layer. This layer may also include a pH indicator for visually confirming cessation of reagent activity.
In another embodiment the dispersion of the suspended reagent may be uniform throughout the reagent layer thus providing an even introduction of the TCA or AHA over time and surface area. The reagent may also be dispersed, or suspended, to provide a vertical concentration gradient to thus provide time dependent reagent delivery rate to the treatment area. Alternately, or additionally, the reagent may be dispersed, or suspended to provide a radial concentration gradient to focus treatment on a particular area (e.g., the cervix opening) while providing lesser or no treatment in other areas covered by the film.
In another related aspect of this invention, an insertion device for attaching the film of this invention includes a concave cup to conform to the generally convex, or toroidal shape of the cervix, the cup having at least an opening for vacuum clamping a therapeutic film of this invention, and a vacuum relief for releasing the film once the film is attached to the cervix. In an alternate embodiment of the insertion device, the therapeutic patch may be provided releasable pre-attached to the concave surface of the insertion tool, which can release the patch once the patch is introduced to the cervix, or the insertion tool left in place while the treatment layer is ablated, and then removed when the treatment layer has sufficiently completed its ablation.
In yet another related aspect of this invention, an assemblage of therapeutic patches, insertion devices, various swabs, saline solution, and, other devices such as speculums are included in a convenient kit in sufficient quantities to provide a complete course of treatment for a single patient therapy session. Variants of the kit will include therapeutic patches having various physical criteria suitable for the condition to be treated. Other variants of the kit include an auxiliary kit adaptable to be included in addition to the above described kit. The auxiliary kit will include solutions, such as Monsel paste and Lugols® solution, and devices, such as a speculum light that can be shared across multiple patient visits.
To accomplish the foregoing and related ends, certain illustrative embodiments of the invention are described herein in connection with the following description and the annexed drawings. These embodiments are indicative, however, of but a few of the various ways in which the principles of the invention may be employed and the present invention is intended to include all such aspects and their equivalents. Other advantages, embodiments and novel features of the invention may become apparent from the following description of the invention when considered in conjunction with the drawings. The following description, given by way of example, but not intended to limit the invention solely to the specific embodiments described, may best be understood in conjunction with the accompanying drawings, in which:
The following embodiments are described in sufficient detail to enable those skilled in the art to make and use the invention. It is to be understood that other embodiments would be evident based on the present disclosure, and that system, process, mechanical, or chemical changes may be made without departing from the scope of the present invention.
In the following description, numerous specific details are given to provide a thorough understanding of the invention. However, it will be apparent that the invention may be practiced without these specific details. In order to avoid obscuring the present invention, some well-known compositions, system configurations, and process steps are not disclosed in detail.
The drawings showing embodiments of the system are semi-diagrammatic and not to scale and, particularly, some of the dimensions are for the clarity of presentation and are shown exaggerated in the drawing figures.
Where multiple embodiments are disclosed and described having some features in common, for clarity and ease of illustration, description, and comprehension thereof, similar and like features one to another will ordinarily be described with similar reference numerals. The embodiments have been numbered first embodiment, second embodiment, etc. as a matter of descriptive convenience and are not intended to have any other significance or provide limitations for the present invention.
The term “therapeutic patch” or “therapeutic film” referred to herein are synonymous and can include single layer, or multi-layer patches, or equivalently “thin films” for application to a dermal surface, The therapeutic patch may be the patch itself, or include an insertion tool to which the patch is affixed, or a combination thereof. For example, the therapeutic patch can be a single or multi-layer composition, or a single or multi-layer composition removably bonded to an insertion tool for facilitating the application of the composition to an affected dermal area. The term “film” as referred to herein refers to that portion of the therapeutic patch in which current context of the description applies.
The term “treatment layer” referred to herein means either a single layer of a therapeutic patch that contains the active reagent for performing the treatment once it has made contact with the affected dermal layer. In one embodiment the treatment layer includes an exfoliating reagent that is either dissolved in a supporting solid substrate, or a dispersed solid or microencapsulated reagent in a supporting substrate.
The term “substrate” referred to herein means the composition in which the active reagent is either dissolved or dispersed as a solid suspension. If a solid suspension then the term “matrix” may be used to describe the composition surrounding and supporting the solid active reagent. The term “dissolvable film” is contextually related to the term substrate or matrix, but more specifically includes the characteristic of being a thin film configured to be a patch that may be applied to a predetermined area of dermis, and being dissolvable in the presence of moisture.
The term “reagent” is synonymous with the term “active reagent” and refers to the non-inert component of a layer in the therapeutic patch. For example, in the treatment layer, an exfoliating reagent such as trichloroacetic acid (TCA) may be dissolved as a liquid in a substrate of a water soluble gel, or the TCA may be dispersed as a solid suspension in a water soluble matrix.
The term “capping layer” referred to herein means an outer layer of the therapeutic patch that is the most distal layer from the affected dermis.
Referring initially to the non-limiting example embodiment shown in
Other suitable films may comprise water soluble polymers, or polymers soluble both in water and organic solvents, such as hydroxypropyl cellulose (HPC) and the like. The film is sized to cover the outer dermal surface of the cervix, but not to extend onto the vaginal epithelium.
The chemexfoliating reagent 4 of the treatment layer 2 of the therapeutic film 1 is selected from chloroacetic acids, including preferably trichloroacetic acid (TCA), and alpha hydroxy acids (AHA) (e.g., glycolic acid, lactic acid, malic acid, citric acid, and tartaric acid).
Effective concentrations of TCA in the treatment layer should be equivalent to between 50% and 100% w/v solutions, and preferably between 60% and 90% w/v. For a 25 mm treatment film that is one mm thick, the amount of TCA loading that is equivalent to a ½ milliliter dose of 85% TCA w/v is approximately 0.8 grams of TCA.
If AHA is used in the treatment layer, the amount of AHA dispersed in the dissolvable film dispensed by the treatment layer should be the equivalent of a volumetric dose of approximately ½ milliliter of 60%-90% AHA w/v solution.
The dissolving substrate should be chemically compatible with the TCA (i.e., non-reactive with the TCA), or whichever chemexfoliating agent is chosen, particularly if the exfoliating reagent is dissolved in the substrate material. As shown in
The TCA may be dispersed evenly throughout the dissolvable film as shown in
In one embodiment, a water-dissolvable therapeutic film is prepared in accordance with the above descriptions and that which is known in the art. Crystalline TCA powder having a particle size of one hundred microns or less, and preferably fifty microns or less, is applied to at least one surface of the film, the surface later to be the dermis side of the therapeutic patch. The film and TCA powder may be further coated with a dissolvable layer, such as with a dissolvable polymer coating. In this regard, a dissolvable film is provided with at least one surface of the film being coated with TCA powder and an optional water-dissolvable coating.
In another embodiment, a water-dissolvable thin film is prepared in accordance with the above and that which is known in the art. Crystalline TCA powder is introduced or embedded within the thin film prior to drying. For example, TCA powder can be encapsulated in a carbohydrate glass, such as glucose or other sugar-glass matrix, and the coated TCA particles can be introduced into the polymer film prior to drying. Some sugars are known to be insoluble in acetone and certain other organic solvents. Upon encapsulating the TCA particles in carbohydrate-glass, the encapsulated TCA particles can then be introduced into an organic solvent such as acetone without dissolving the TCA particles. Thus, a polymer such as hydroxypropyl cellulose (HPC), which is bi-soluble in both organic solvents (ex: acetone) and water, can be used to manufacture the films. In sum, HPC is dissolved in acetone forming a polymer solution. TCA powder is encapsulated in a carbohydrate-glass, and the encapsulated TCA powder is introduced into the polymer solution and mixed. Note that the encapsulated TCA will not dissolve in the organic solvent because it is coated with a protective encapsulating layer of sugar-glass (which is not soluble in acetone). The polymer solution and suspended TCA powder is then cast and dried to form the film. The resulting film will include the carbohydrate-glass coated TCA powder suspended in the polymer substrate. Now, with exposure to a moist environment, such as the cervix of a patient, the film which is also water-soluble will begin to ablate, thereby exposing the carbohydrate-glass coated TCA powder to the cervix, the carbohydrate glass is also soluble in water and thus begins the erosion of the carbohydrate-glass encapsulating layer thereby exposing the TCA powder, which in the moist environment will dissolve into a liquid-phase acid for treating a surface layer of epithelial cells about the cervix.
In yet another embodiment, an amount of liquid TCA is introduced into an aqueous solution containing a water-soluble polymer prior to drying. Films are cast or otherwise manufactured from the polymer solution.
In addition to HPC, certain forms of cellulose acetate may provide a suitable bi-soluble polymer for forming water-dissolvable films.
The therapeutic patch of
The therapeutic patch of
The capping layer 6 may be extended to not only cover the distal surface 8 of the treatment layer 2, but the perimeter walls 7 of the treatment layer as well as shown in
Additionally, one or more biologically acceptable tacking agents can be embodied in the capping layer to form a tacky paste or similar layer when the treatment layer is completely dissolved. Any known tacking agent that is suitable for topical biological application may be used. In some embodiments, it may be desirable to provide carbohydrate-glass encapsulated hydrogel microspheres as an exemplary tacking agent. Similar to the carbohydrate-glass encapsulated TCA, the carbohydrate-glass encapsulating layer will erode in the moist environment of the cervix, exposing the hydrogel microspheres which then absorb moisture and form a tacky layer covering the application site.
Thus, in a multi-layer film, a first layer may include a treatment layer comprising TCA or AHA; whereas a second layer may include a tacking agent such as carbohydrate-glass encapsulated hydrogel microspheres. In this embodiment, the second layer forms the “capping layer” of the film. Because it is important to apply the first layer to the surface of the target delivery site, the first and/or second layers can be individually marked to identify the surface which should be applied. The marking may consist of any visual representation, preferably a color or marking.
In another embodiment, and as shown in
As the treatment layer surface is very hygroscopic and self-attaches itself and start dissolving upon contacting any moist epithelial surface, including the vaginal walls, it is desirable to isolate the treatment layer's exposed surface from intermediate epithelial surfaces upon insertion of the therapeutic film through the vaginal canal. The insertion tool 20 of
The insertion device shown in
A cross section view of the insertion device of
In another embodiment, the therapeutic film may come pre-attached to an insertion device as shown in
In another embodiment, the insertion tool may include a hollow cup portion 30 as shown in
In other embodiments, a therapeutic composition comprising a chemexfoliating agent is applied to a cervix of the patient. A method for administering the chemexfoliating agent may comprise, in any order: (i) providing a therapeutic composition comprising a chemexfoliating agent; (ii) first applying an initial amount of the therapeutic composition to at least a portion of a cervical epithelium of a patient; (iii) at least forty eight hours after said first applying: second applying a subsequent amount of the therapeutic composition to the at least a portion of the cervical epithelium of the patient. The method may further comprise: placing the patient in a dorsolithotomy position; introducing a speculum into a vagina of the patient to expose a cervix of the patient, the cervix including the cervical epithelium; clearing discharge or secretion using a swab; visualizing the cervix for gross abnormalities; removing the speculum from the vagina of the patient; or a combination thereof.
The method of claim 17, wherein said chemexfoliating agent comprises trichloroacetic acid (TCA).
The method of claim 19, wherein said chemexfoliating agent comprises TCA in a composition of between 45% and 85% weight to volume in aqueous solution.
Other variations of the instant disclosed features and embodiments, particularly when combined with other features and methods known in the art, are deemed to be included within the spirit and scope of this disclosure.
This application claims the benefit of U.S. Provisional Application No. 62/182,606, filed Jun. 21, 2015, and U.S. Provisional Application No. 62/120,356, filed Feb. 24, 2015; each of which is hereby incorporated by reference.
Number | Date | Country | |
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62182606 | Jun 2015 | US | |
62120356 | Feb 2015 | US |