The present methods and devices belong to the field of control temperature for aerosol generation of a drug.
In CN1548934 A a sensor and a circuit to detect the temperature of a heating element are described. Measuring the heating is stopped and the heating element is allowed to stabilize the temperature for a suitable period of time.
In WO03037412A2 a method of controlling the temperature profile of a resistive element for vaporising a medicament is disclosed. Said method includes a pulse heating with a first high duty cycle for the ramp up and a reduced duty cycle to maintain the temperature. The timing of temperature determination is not specified. The device produces a cool central region and a hot region around the centre.
In WO07076688 A1 a method of controlling the temperature of a heating element where the electrical resistance changes monotonically with temperature and where the temperature is sensed after the heating has stopped is described.
In WO14040988 A2 a method of maintaining the temperature of an aerosol generating device providing pulses of electrical current (duty cycle) is described. The method includes determining the temperature of the heating element by determining its resistance and the duty cycle is reduced when the temperature is closer to the target temperature by adjusting the electrical current, e.g., by limiting the voltage applied. The aerosol-forming substrate is based on tobacco.
In US2021219386 AA and US2021145074 an apparatus including two switches; a first switch to interrupt the flow of current to heat a resistive heating element that causes vaporization of a vaporizable material and a second switch to add a reference resistor in series with the resistive heating element is described. The apparatus allows to determine the resistance of the resistive heating element and controlling the amount of power supplied to the resistive heating element based on the determined resistance by adjusting the flow of current.
In WO2015192084A1 an electronic vaporizer including a heating element to heat a fluid to produce a vapour as described. Said vaporizer includes a power control unit configured to regulate the electrical power supplied to the heating element. The regulation is based at least in part in the temperature of the heating element and the temperature setting in order to avoid that the heating element exceeds its temperature setting. The temperature of the heating element may be measured using its resistance based on the known temperature coefficient of resistance characteristics associated with the heating element, the temperature may be determined as often as once every 100 ms. In a different embodiment, the vaporizer includes a machine-readable medium with the temperature coefficient resistance stored in it. The main objective of the vaporizer is to avoid overheating the vapour and maintain the temperature around the boiling point of the fluid. An electronic vaporizer including a heating element to heat a fluid to produce a vapour is described. Said vaporizer includes a power control unit configured to regulate the electrical power supplied to the heating element. The regulation is based at least in part in the temperature of the heating element and the temperature setting in order to avoid that the heating element exceeds its temperature setting. The temperature of the heating element may be measured using its resistance based on the known temperature coefficient of resistance characteristics associated with the heating element, the temperature may be determined as often as once every 100 ms. In a different embodiment, the vaporizer includes a machine-readable medium with the temperature coefficient resistance stored in it. The main objective of the vaporizer is to avoid overheating the vapour and maintain the temperature around the boiling point of the fluid.
In WO2019152873 a disposable cartridge with a drug coated on an electrically heated drug foil substrate is described. The disposable cartridge can be connected to a handheld controller which includes the electronics and electrical components, including the electricity source. The drug foil substrate is heated with a ramp-up to a target temperature and then a heating rate is applied. The heating rate is selected between plateau heating, tampered cooling, and progressive heating. However, the document does not describe how to accurately control the temperature during the ramp-up and heating rate resulting in a high dispersion of the emitted dosc.
The heating of a drug foil substrate to generate an aerosol may be affected by the voltage of the battery which may be different depending on its charging level and may vary, as well, during any given heating cycle if high currents are applied.
The current output of the battery, which as well affects the heating of a drug foil substrate to generate an aerosol, may change depending on its charge level and during any given heating cycle when high currents are applied.
Further, depending on the ambient temperature the heat dissipation from the drug foil substrate may vary from inhalation to inhalation and even during a given inhalation.
Not only that, but the process when the drug of the foil substrate evaporates absorbs energy (known as enthalpy of vaporization), and that extra energy needs to be added in a precise moment, which cannot be foretold, and not in another moment.
Further, on one side, if the heating duration is too short the drug foil substrate may not rest enough time at the temperature required for the evaporation of the drug and the emitted dose will be lower than that required for the therapy, if it is too long the drug foil substrate may rest longer time at the temperature required for the evaporation of the drug and the emitted dose will be higher than the required for the therapy and possibly with more impurities.
Additionally, on another side, if the drug foil substrate is overheated, the aerosol produced may have increased impurities and the emitted dose may be higher than that required for the therapy, on the other side if it is underheated the emitted dose may be lower than that required for the therapy.
In condensation aerosol delivery systems, the aerosol quality of some drugs is very sensitive to the temperature used to vaporize the drug (see e.g., Comparative Example 1 and
In the prior art, electric heating is mainly used in the field of e-cigarettes to heat tobacco, herbal derivatives, or liquid formulations. The temperature control in that field is important in order to provide a suitable particle size and aerosol dosing, but in the field of drug administration, it is much more important to accurately control those parameters in order to administer a precise and reproducible dose of the drug in order to achieve its therapeutic effect without any undesired side effect. Further, the purity of the administered drug is as well of capital importance in the field of drug administration.
Thus, there is a need for a method and device capable of accurately controlling the heating profile of a drug foil substrate so that it is at the desired temperature at each moment of the heating profile.
A first aspect discloses a method of electrically heating a drug foil substrate (205), coated with a solid drug film (207), placed in a disposable cartridge (200) following a first temperature vs. time profile (TP1) to generate a condensation aerosol; the disposable cartridge (200) is suitable to be connected to a handheld controller (100);
A second aspect is a disposable cartridge (200) configured to perform the method of the first aspect and suitable to be connected to the handheld controller (100) of a third aspect including:
A third aspect is a handheld controller (100) configured to perform the method of the first aspect and suitable to be connected to the disposable cartridge (200) of the second aspect including:
A fourth aspect is a medicament including a drug selected from: loxapine, alprazolam, estazolam, fentanyl, zaleplon, almorexant, apomorphine, pergolide, ropinirole, pramipexol, granisetron, ondansetron, palonosetron, nicotine, nicotine meta-salicylate, rotigotine, or its pharmaceutically acceptable salts for use in the method of the first aspect, the handheld controller (100) of the third aspect or the disposable cartridge (200) of the second aspect.
The fifth aspect is a drug deposited on a drug foil substrate (205) of the method of the first aspect, the handheld controller (100) of the third aspect or the disposable cartridge (200) of the second aspect for use in a condition or episode, where the drug is:
Within the present document, the following terms are used with the following meanings.
The first temperature profile (TP1) includes several t_period1, each of which, as illustrated in
The temperature can be calculated using measurement of electrical resistance across the drug foil substrate (205), optical measurement, direct contact measurement with a thermocouple and/or any other method known.
The resistance of the drug foil substrate is measured e.g., using a circuit as the one illustrated in
V=I·R
The measurement circuit (see
The measurement of the voltage drop (V3−V4) due to the known resistor Y Ω (see
I_meas is used, along with the voltage drop around the drug foil substrate, V2−V1 (see
On summary, the resistance (R205) of the drug foil substrate (205) can be calculated as (see
The drug foil substrate has a resistance vs. temperature relationship, i.e., at each temperature it has a different resistance. This relationship can be determined for every drug foil substrate (or a number of them) during manufacturing of the disposable cartridge by heating the drug foil substrate (205) to a set of predetermined temperatures and measuring the corresponding resistance, and the relationship stored in the disposable cartridge.
The temperature can be measured as well using an optical measurement, i.e., by detecting the amount of infrared energy emitted by the drug foil substrate. Its emission properties can be determined for every drug foil substrate (or a number of them) during manufacturing of the disposable cartridge and the relationship stored in the disposable cartridge.
The temperature can be measured as well using direct contact measurement with a thermocouple calibrated for the desired temperature range.
TP1 is illustrated in the flowchart in
In TP1 an embodiment is that one of t_heat1 and t_wait1 is 0 and the other one is t_period1-t_meas1 (see
The next step in
The selection of ratio between t_heat1 and t_wait1 for the second case depends on the performance of the drug (sensibility to temperature, enthalpy of vaporization, and the like) to be vaporized. If it desired that the temperature is not much higher than T_exp, then if T_meas≥T_exp then t_heat1=0 (such as in
Sometimes it is preferred that the temperature is not much lower than T_exp, then if T_meas≥T_exp then t_heat1 can be selected based on the temperature slope of the previous t_period1 so that at the end of the following t_period1 the T_exp (dash line in
Any other ratio between t_heat1 and t_wait1 can be selected depending on the drug to be vaporized. Furthermore, the ratio between t_heat1 and t_wait1 may vary during TP1, for instance it may be desirable to reduce t_heat1 and increase t_wait when approaching tTTP1 in order to avoid surpassing said tTTP1.
The process is repeated until the desired temperature is reached (T_meas≥ tTTP1) or the time for TP1 (HtTP1) has elapsed.
If after the tTTP1 has been reached or HtTP1 has elapsed, it is necessary to control the temperature for longer time or follow subsequent temperature profile, then TP2 is followed.
The flowchart for method following TP2 is illustrated in the flow chart in
In TP2, an embodiment is that both of t_heat2 and t_wait2 are different from 0 and the other one is t_period2−t_meas2 (see
The next step in TP2 (
Then T_meas is compared with the expected temperature for this moment according to the temperature time relationship based on TP2, T_exp, and the next t_heat2 and t_wait2 are set. if T_meas≤T_exp then t_wait2=098% and t_heat1=1−98% of t_period2 (such as in
The selection of the ratio between t_heat2 and t_wait2 for the second case depends on the performance of the drug (sensibility to temperature, enthalpy of vaporization, and the like) to be vaporized. If it desired that the temperature is not much higher than T_exp, then if T_meas≥T_exp then t_heat2=0 (such as in
The process is repeated until the desired temperature is reached (T_meas≥ tTTP2) or the time for TP2 (HtTP2) has elapsed.
A process of aerosol generation is illustrated in
Embodiment 1. A method of electrically heating a drug foil substrate (205), coated with a solid drug film (207), placed in a disposable cartridge (200) following a first temperature vs. time profile (TP1) to generate a condensation aerosol; the disposable cartridge (200) is suitable to be connected to a handheld controller (100);
Embodiment 2. The method of the previous Embodiment which further includes a second temperature vs. time profile (TP2) immediately after the end of TP1;
Embodiment 3. The method according to any of the previous Embodiments, where the heating function in TP1 is a line, a power function, polynomial function, step-function, or a logarithmic function; or in another embodiment the function is a line.
Embodiment 4. The method according to any of the previous Embodiments, where HSTP1 ranges between 1.25 and 4.5° C./ms, in another embodiment between 1.5 and 4.0° C./ms, in another embodiment between 1.75 and 3.5° C./ms, or in another embodiment between 1.75 and 3.0° C./ms.
Embodiment 5. The method according to any of the previous Embodiments, where tTTP1 ranges between 200 and 400° C., in another embodiment between 225 and 390° C., in another embodiment between 25° and 380° C., in another embodiment between 275 and 370° C., or in another embodiment between 30° and 360° C.
Embodiment 6. The method according to any of the previous Embodiments, where HtTP1 ranges between 40 and 400 ms, in another embodiment between, 50 and 350 ms, in another embodiment between 75 and 300 ms, in another embodiment between 90 and 250 ms in another embodiment between 100 and 200 ms, or in another embodiment between 125 and 180 ms.
Embodiment 7. The method according to any of the previous Embodiments, where t_period1 ranges between 0.55 and 4.0 ms, in another embodiment between 0.6 and 3.5 ms, in another embodiment between 0.7 and 3.0 ms, in another embodiment between 0.75 and 2.5 ms, in another embodiment between 0.8 and 2.0 ms, or in another embodiment between 0.9 and 1.75 ms.
Embodiment 8. The method according to any of the previous Embodiments, where t_meas1 ranges between 5 and 35% of t_period1, in another embodiment between 10 and 30% of t_period1, in another embodiment between 15 and 25% of t_period1, or in another embodiment between 15 and 22% of t_period1.
Embodiment 9. The method according to any of the previous Embodiments, where ITP1 ranges between 30 and 300 A, in another embodiment between 50 and 290 A, in another embodiment between 75 and 280 A, in another embodiment between 100 and 280 A, in another embodiment between 125 and 260 A, in another embodiment between 150 and 250 A, or in another embodiment between 175 and 240 A.
Embodiment 10. The method according to any of the previous embodiments, where when T_meas is lower than tTTP1, then c) is if T_meas≤ T_exp then t_heat1=90100% of (t_period1−t_meas1) and t_wait1=t_period1−t_meas1−t_heat1, if not t_heat1=0% of (t_period1−t_meas1) and t_wait1=t_period1−t_meas1−t_heat1.
Embodiment 11. The method according to any of the previous Embodiments, where when T_meas is higher than (TTP1−50° C. and lower than (TTP1−20° C., then c) is if T_meas≤T_exp then t_heat1=7090% of (t_period1−t_meas1) and t_wait1=t_period1−t_meas1−t_heat1, if not t_heat1=0% of (t_period1−t_meas1) and t_wait1=t_period1−t_meas1−t_heat1.
Embodiment 12. The method according to any of the previous Embodiments, where when T_meas is higher than (TTP1−20° C., then c) is if T_meas≤ T_exp then t_heat1=40-60% of (t_period1−t_meas1) and t_wait1=t_period1−t_meas1−t_heat1, if not t_heat1=0% of (t_period1−t_meas1) and t_wait1=t_period1−t_meas1-t_heat1.
Embodiment 13. The method according to any of the previous Embodiments, when T_meas is lower than tTTP1−50° C., step c) is
Embodiment 14. The method according to any of Embodiment 2 to Embodiment 13, where the heating function in TP2 is a line, a power function, polynomial function, step-function, or a logarithmic function; in another embodiment the function is a line.
Embodiment 15. The method according to any of Embodiment 2 to Embodiment 14, where HSTP2 ranges between −0.13 and 0.13° C./ms, in another embodiment between −0.1 and 0.1° C./ms, in another embodiment between −0.08 and 0.08° C./ms, or in another embodiment between −0.05 and 0.08° C./ms.
Embodiment 16. The method according to any of Embodiment 2 to Embodiment 15, where tTTP2 ranges between 20° and 400° C., in another embodiment between 225 and 390° C., in another embodiment between 25° and 380° C., in another embodiment between 275 and 370° C., or in another embodiment between 30° and 360° C.
Embodiment 17. The method according to any of Embodiment 2 to Embodiment 16, where HtTP2 ranges between 0.5 and 1500 ms, in another embodiment between 0.5 and 1000 ms, in another embodiment between 1.5 and 500 ms, in another embodiment between 2.5 and 250 ms, in another embodiment between 3.0 and 125 ms, in another embodiment between 4.5 and 75 ms, in another embodiment between 5.0 and 50 ms, or in another embodiment between 5.5 and 25 ms.
Embodiment 18. The method according to any of Embodiment 2 to Embodiment 17, where t_period2 ranges between 0.55 and 4.0 ms, in another embodiment between 0.6 and 3.5 ms, in another embodiment between 0.7 and 3.0 ms, in another embodiment between 0.75 and 2.5 ms, in another embodiment between 0.8 and 2.0 ms, or in another embodiment between 0.9 and 1.75 ms.
Embodiment 19. The method according to any of Embodiment 2 to Embodiment 18, where t_meas2 ranges between 5 and 35% of t_period2, in another embodiment between 10 and 30% of t_period2, in another embodiment between 15 and 25% of t_period2, or in another embodiment between 15 and 22% of t_period2.
Embodiment 20. The method according to any of Embodiment 2 to Embodiment 19, where ITP2 ranges between 12 and 45 A, in another embodiment between 15 and 40 A, in another embodiment between 17 and 35 A, in another embodiment between 20 and 30 A, or in another embodiment between 22 and 27 A.
Embodiment 21. The method according to any of Embodiment 2 to Embodiment 20, where in step C) is
Embodiment 22. The method according to any of the previous Embodiments, where the resistance of the drug foil substrate (205) ranges between 1 and 200 mΩ, in another embodiment between 5 and 100 mΩ in another embodiment between 10 and 75 mΩ, in another embodiment between 12 and 50 mΩ, in another embodiment between 12 and 20 mΩ, or in another embodiment between 13 and 20 mΩ.
Embodiment 23. The method according to any of the previous Embodiments, where the drug foil substrate (205) is a metallic drug foil substrate (205).
Embodiment 24. The method according to the previous Embodiment, where the metallic drug foil substrate (205) is a stainless-steel drug foil substrate (205).
Embodiment 25. The method according to any of the previous Embodiments, where the temperature sensor is selected between measurement of electrical resistance across the drug foil substrate (205), optical measurement, and/or direct contact measurement with a thermocouple.
Embodiment 26. The method according to the previous Embodiment, where the temperature sensor is measurement of electrical resistance across the drug foil substrate (205).
Embodiment 27. The method according to the previous Embodiment, where T_meas is measured applying a measurement current I_meas to the drug foil substrate (205) and I_meas ranges between 0.1 and 20 A, in another embodiment between 0.5 and 15 A, in another embodiment between 1 and 10 A, in another embodiment between 1.5 and 7 A, or in another embodiment between 2 and 5 A.
Embodiment 28. The method according to any of Embodiment 26 to Embodiment 27, where the predetermined temperature vs. resistance relationship of the drug foil substrate (205) is stored in a memory (230) of the disposable cartridge (200).
Embodiment 29. The method according to any of the previous Embodiments, where the temperature sensor is measurement of electrical resistance across the drug foil substrate (205) and T_meas is measured applying a measurement current I_meas to the drug foil substrate (205) and I_meas ranges between 0.1 and 20 A, in another embodiment between 0.5 and 15 A, in another embodiment between 1 and 10 A, in another embodiment between 1.5 and 7 A, or in another embodiment between 2 and 5 A.
Embodiment 30. The method according to any of the previous Embodiments, where the HSTP1; tTTP1, and/or HtTP1 are stored in a memory (230) of the disposable cartridge (200).
Embodiment 31. The method according to any of Embodiment 2 to Embodiment 30, where the HSTP2; tTTP2, and/or HtTP2 are stored in a memory (230) of the disposable cartridge (200).
Embodiment 32. The method according to any of the previous Embodiments, where the voltage is from 3 to 13 V, in another embodiment is the voltage is from 3 to 4 V, in another embodiment the voltage is from 6 to 8 V, or in another embodiment the voltage is from 10 to 12 V.
Embodiment 33. A disposable cartridge (200) configured to perform the method of any of the previous Embodiments and suitable to be connected to the handheld controller (100) of any of Embodiment 39 to Embodiment 45 including:
Embodiment 34. The disposable cartridge (200) of the previous Embodiment, further including a memory (230) and data connections (301) between the memory and the handheld controller (100) of any of Embodiment 39 to Embodiment 45.
Embodiment 35. The disposable cartridge (200) of the previous Embodiment, where the memory (230) is a long-term memory (including volatile, non-volatile, or semi-volatile memory), a bar code, a QR code or RFID.
Embodiment 36. The disposable cartridge (200) of any of Embodiment 34 to Embodiment 35, where the memory (230) includes the temperature vs. resistance relationship of the drug foil substrate (205).
Embodiment 37. The disposable cartridge (200) of any of Embodiment 33 to Embodiment 36, where the memory (230) includes the HSTP1; tTTP1, and/or HtTP1.
Embodiment 38. The disposable cartridge (200) of any of Embodiment 33 to Embodiment 37, where the memory (230) includes the HSTP2; tTTP2, and/or HtTP2.
Embodiment 39. A handheld controller (100) configured to perform the method of any of Embodiment 1 to Embodiment 31 and suitable to be connected to the disposable cartridge (200) of any of Embodiment 33 to Embodiment 38 including:
Embodiment 40. The handheld controlled of the previous Embodiment where at least one battery (101) is capable of providing between 3 and 12 V, in another embodiment between 4 and 11 V, in another embodiment between 5 and 10 V, in another embodiment between 6 and 10 V, or in another embodiment between 7 and 9 V.
Embodiment 41. The handheld controller (100) of any of Embodiment 39 to Embodiment 40 where at least one battery (101) is capable of delivering peak currents higher than 30 A, in another embodiment higher than 50 A, in another embodiment higher than 75 A, in another embodiment higher than 100 A, in another embodiment higher than 125 A, in another embodiment higher than 150 A, or in another embodiment higher than 175 A.
Embodiment 42. The handheld controller (100) of any of Embodiment 39 to Embodiment 41, which further includes an airflow sensor which triggers the heating of the drug foil substrate (205).
Embodiment 43. The handheld controller (100) of the previous Embodiment, where the airflow sensor is selected from a differential pressure sensor, one or more thermistors, an air flow or sail switch, a hot wire anemometer, or vane anemometer.
Embodiment 44. The handheld controller (100) of any of Embodiment 42 to Embodiment 43, where the airflow sensor triggers the heating of the drug foil substrate at an airflow higher than 7 L/min; in another embodiment higher than 14 L/min; in another embodiment higher than 20 L/min; in another embodiment higher than 30 L/min, or in another embodiment the airflow is between 7 and 35 L/min.
Embodiment 45. A handheld controller (100) of any of Embodiment 39 to Embodiment 44 or a disposable cartridge (200) of any of Embodiment 33 to Embodiment 38 for use in therapy.
Embodiment 46. The method according to any of Embodiment 1 to Embodiment 31, handheld controller (100) of any of Embodiment 39 to Embodiment 45 or the disposable cartridge (200) of any of Embodiment 33 to Embodiment 38, for use in a condition or episode where when the drug in the solid drug film (207) is selected from:
Embodiment 47. A method of treatment for a condition or episode which includes administering a drug included in the solid drug film (207) coated on at least a portion of the drug foil substrate (205) of the method according to any of Embodiment 1 to Embodiment 31, handheld controller (100) of any of Embodiment 39 to Embodiment 45 or the disposable cartridge (200) of any of Embodiment 33 to Embodiment 38, where when the drug in the solid drug film (207) is selected from:
Embodiment 48. Use of the method according to any of Embodiment 1 to Embodiment 31, previous embodiments, handheld controller (100) of any of Embodiment 39 to Embodiment 45 (previous embodiments) or the disposable cartridge (200) of any of Embodiment 33 to Embodiment 38 for the manufacturing of a medicament for the treatment of a condition or episode; where when the drug in the solid drug film (207) is selected from:
Embodiment 49. A medicament including a drug selected from: loxapine, alprazolam, estazolam, fentanyl, zaleplon, almorexant, apomorphine, pergolide, ropinirole, pramipexol, granisetron, ondansetron, palonosetron, nicotine, nicotine meta-salicylate, rotigotine, or its pharmaceutically acceptable salts for use in the method according to any of Embodiment 1 to Embodiment 31, (previous embodiments) handheld controller (100) of any of Embodiment 39 to Embodiment 45 or the disposable cartridge (200) of any of Embodiment 33 to Embodiment 38.
Embodiment 50. A drug deposited on a drug foil substrate (205) of the method according to any of Embodiment 1 to Embodiment 31, handheld controller (100) of any of Embodiment 39 to Embodiment 45 or the disposable cartridge (200) of any of Embodiment 33 to Embodiment 38 for use in a condition or episode, when the drug is:
The temperature is measured using FLIR Systems infrared cameras, Thermacam SC3000 and A655sc. The SC3000 infrared camera uses quantum well infrared photodetector technology, and the A655sc uses an uncooled microbolometer detector. These cameras are adequate for high sensitivity and accuracy and captures images up to 180 and 200 Hz, respectively. Temperature is calculated based on the amount of emitted infrared light. The camera was calibrated by heating the metal cylinders (resistive heating with a constant current DC power supply) to various steady-state temperatures between 20° and 400° C. and measuring the actual temperature with calibrated thermocouples (Omega, Stamford, CT).
A testing device where a Heat Source 1 is mechanically and electrically attached as shown in
A 100 mm long device such as that in
An 89 mm long device such as that in
A 12.7×63.5, 0.127 mm 304-stainless steel drug foil substrate attached to Device 1 with connexions to receive electrical power from an electrical source. Devices were actuated with a constant airflow of ˜ 30 L/min. An example is depicted in
A 47.2×47.2×0.38 mm 304-stainless steel drug foil substrate is attached to a chemical heat package connected to Device 2. One chemical heat package is shown in
Information on chemical heating packs can be found in WO2004104492, incorporated herein by reference.
In chemical heat package devices, an exothermic thermite reaction from the reactants inside of the heat package rapidly propagated (˜ 0.1 s) and generated heat nearly instantaneously, which vaporized the drug film. The reactants are calibrated to heat the drug foil substrate to a given temperature. Upper and lower housings were welded prior to vaporization. Devices were actuated with a constant airflow of ˜ 30 L/min.
A 31×28×0.127 mm 304-stainless steel drug foil substrate with electrical connections, such as the one in
mg apomorphine HCl (APO) was coated on 2.27 cm2 (0.44 mg/cm2) on the drug foil substrate of Heat Source 1 or 2 and heated to the temperatures specified in the table below.
This data is plotted in
An uncoated drug foil substrate of Heat Source 3 but modified to incorporate a window of calcium fluoride (which is transparent to IR light) was heated using the method where if T_meas≤ T_exp then t_heat1=t_period1−t_meas1 else t_wait1=t_period1−t_meas1. In this example HSTP1 is 1.5° C./ms, tTTP1 is 350° C., t_period_1 is 1.3 ms and t_meas1 is 0.3 ms. The temperature is measured using a resistance of the drug foil substrate vs. temperature relationship using a circuit as that in
When T_meas is close to tTTP1 then when T_meas≤T_exp then t_heat1=10% (t_period1−t_meas1) else t_wait1=t_period1−t_meas1 in order to have a smoother curve and prevent overheating the drug foil substrate. That is why the plot in
For TP2, HSTP2 is −0.05° C./ms, tTTP2 is 313° C.
The same device and conditions as in Example 1 were used but with HSTP1=2.0° C./ms, tTTP1=309° C., HSTP2=0° C./ms, and tTTP2 is 309° C. nine different uncoated drug foil substrates were used.
The reference numbers in the figures mean:
Various embodiments are called out for example purposes and are in no way meant to be limiting.
Number | Date | Country | |
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63289606 | Dec 2021 | US |
Number | Date | Country | |
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Parent | PCT/US2022/052909 | Dec 2022 | WO |
Child | 18742331 | US |