Claims for Patent: 5,212,199

Summary for Patent: 5,212,199

Title:	Sorbitan esters as skin permeation enhancers
Abstract:	Skin permeation enhancer compositions are provided which increase the permeability of skin to transdermally administered pharmacologically active agents. The compositions contain a sorbitan ester in addition to the selected pharmacologically active agent, and may also contain a C.sub.1 -C.sub.4 aliphatic alcohol. Methods and transdermal drug delivery systems for using the compositions are also provided.
Inventor(s):	Heiber; Sonia (Salt Lake City, UT), Patel; Dinesh (Murray, UT), Ebert; Charles D. (Salt Lake City, UT)
Assignee:	Theratech, Inc. (Salt Lake City, UT)
Application Number:	07/871,643
Patent Claims:	1. A method for enhancing the rate of penetration of a pharmacologically active agent through the skin, comprising applying to a selected area of intact skin: (a) a therapeutically effective amount of the pharmacologically active agent; and (b) a permeation enhancer consisting essentially of a sorbitan ester having the structural formula ##STR2## wherein R.sub.1 has the formula --O(CO)R', R' is selected from the group consisting of saturated, mono-unsaturated, di-unsaturated, or tri-unsaturated aliphatic hydrocarbon substituents of 7 to 21 carbon atoms optionally containing 1 to 3 hydroxyl groups, and R.sub.2 and R.sub.3 are independently selected from the group consisting of hydroxyl and --O(CO)R'. 2. The method of claim 1 wherein R' is selected from the group consisting of saturated, mono-unsaturated, di-unsaturated, or tri-unsaturated aliphatic hydrocarbon substituents of 11-21 carbon atoms optionally containing 1-3 hydroxyl groups, and R.sub.2 and R.sub.3 are both hydroxyl. 3. The method of claim 2 wherein the sorbitan ester is selected from the group consisting of sorbitan monooleate, sorbitan monolaurate, and mixtures thereof. 4. The method of claim 1 wherein the pharmacologically active agent is pindolol. 5. The method of claim 1, wherein the pharmacologically active agent and the enhancer are present in a single pharmaceutical composition, and wherein the composition further includes a pharmaceutically acceptable inert vehicle. 6. A method for enhancing the rate of penetration of a pharmacologically active agent through the skin, comprising applying to a selected area of intact skin: (a) a therapeutically effective amount of the pharmacologically active agent; and (b) a permeation enhancer consisting essentially of a sorbitan ester having the structural formula ##STR3## wherein R.sub.1 has the formula --O(CO)R', R' is selected from the group consisting of saturated, mono-unsaturated, di-unsaturated, or tri-unsaturated aliphatic hydrocarbon substituents of 7 to 21 carbon atoms optionally containing 1 to 3 hydroxyl groups, and R.sub.2 and R.sub.3 are independently selected from the group consisting of hydroxyl and--O(CO)R', and a C.sub.1 -C.sub.4 aliphatic alcohol. 7. The method of claim 1 wherein R' is selected from the group consisting of saturated, mono-unsaturated, di-unsaturated, or tri-unsaturated aliphatic hydrocarbon substituents of 11-21 carbon atoms optionally containing 1-3 hydroxyl groups, and R.sub.2 and R.sub.3 are both hydroxyl. 8. The method of claim 7 wherein the sorbitan ester is selected from the group consisting of sorbitan monooleate, sorbitan monolaurate, and mixtures thereof. 9. The method of claim 6 wherein the c.sub.1 -C.sub.4 aliphatic alcohol is selected from the group consisting of ethanol, n-propanol, isopropanol, t-butanol, and mixtures thereof. 10. The method of claim 6, wherein the pharmacologically active agent and the enhancer are present in a single pharmaceutical composition, and wherein the composition further includes a pharmaceutically acceptable inert vehicle. 11. A composition of matter for the transdermal administration of a pharmaceutically active agent, comprising: (a) a therapeutically effective amount of the pharmacologically active agent; and (b) a permeation enhancer consisting essentially of a sorbitan ester having the structural formula ##STR4## wherein R.sub.1 has the formula --O(CO)R', R' is selected from the group consisting of saturated, mono-unsaturated, di-unsaturated, or tri-unsaturated aliphatic hydrocarbon substitutuents of 7 to 21 carbon atoms optionally containing 1 to 3 hydroxyl groups, and R.sub.2 and R.sub.3 are independently selected from the group consisting of hydroxyl and --O(CO)R'. 12. The composition of claim 11 wherein the sorbitan ester has the structural formula ##STR5## wherein R.sub.1 has the formula --O(CO)R', where R' is selected from the group consisting of saturated, mono-unsaturated, di-unsaturated, or tri-unsaturated aliphatic hydrocarbon substituents of 7 to 21 carbon atoms optionally containing 1 to 3 hydroxyl groups, and R.sub.2 and R.sub.3 are independently selected from the group consisting of hydroxyl and --O(CO)R'. 13. The composition of claim 12 wherein R' is selected from the group consisting of saturated, mono-unsaturated, di-unsaturated, or tri-unsaturated aliphatic hydrocarbon substituents of 11-21 carbon atoms optionally containing 1-3 hydroxyl groups, and R.sub.2 and R.sub.3 are both hydroxyl. 14. The composition of claim 13 wherein the sorbitan ester is selected from the group consisting of sorbitan monooleate, sorbitan monolaurate, and mixtures thereof. 15. The composition of claim 11 wherein the pharmacologically active agent is pindolol. 16. The composition of claim 11 further including a pharmaceutically acceptable inert vehicle. 17. A composition of matter for the transdermal administration of a pharmacologically active agent comprising: (a) a therapeutically effective amount of the pharmacologically active agent; and (b) a permeation enhancer consisting essentially of a sorbitan ester having the structural formula ##STR6## wherein R.sub.1 has the formula --O(CO)R', R' is selected from the group consisting of saturated, mono-unsaturated, di-unsaturated, or tri-unsaturated aliphatic hydrocarbon substituents of 7 t 21 carbon atoms optionally containing 1 to 3 hydroxyl groups, and R.sub.2 and R.sub. are independently selected from the group consisting of hydroxyl and --O(CO)R', and a C.sub.1 -C.sub.4 aliphatic alcohol. 18. The composition of claim 17 wherein R' is selected from the group consisting of saturated, mono-unsaturated, di-unsaturated, or tri-unsaturated aliphatic hydrocarbon substituents of 11-21 carbon atoms optionally containing 1-3 hydroxyl groups, and R.sub.2 and R.sub.3 are both hydroxyl. 19. The composition of claim 18 wherein the sorbitan ester is selected from the group consisting of sorbitan monooleate, sorbitan monolaurate, and mixtures thereof. 20. The composition of claim 17 wherein the C.sub.1 -C.sub.4 aliphatic alcohol is selected from the group 21. The composition of claim 17 wherein the pharmacologically active agent is pindolol.