Claims for Patent: 10,603,293

Summary for Patent: 10,603,293

Title:	Solid-forming local anesthetic formulations for pain control
Abstract:	Solid-forming local anesthetic formulations for pain control can include a lidocaine base and tetracaine base, polyvinyl alcohol, water, and an emulsifier. The formulation can be prepared to be in a semi-solid state prior to application to a skin surface, can form a soft solidified layer after application, and can provide pain relief when applied to a skin surface proximate a pain site.
Inventor(s):	Zhang; Jie (Salt Lake City, UT)
Assignee:	Crescita Therapeutics Inc. (Mississauga, CA)
Application Number:	16/008,417
Patent Claims:	1. A formulation for pain control, comprising: from about 4 wt % to about 10 wt % lidocaine; from about 4 wt % to about 10 wt % tetracaine; from about 10 wt % to about 18 wt % polyvinyl alcohol; from about 2 wt % to about 6 wt % of an emulsifier selected from sorbitan monopalmitate or sorbitan monostearate; from about 25.94 wt % to about 51.87 wt % water; from about 2 wt % to about 13 wt % petrolatum; and from about 18 wt % to about 36 wt % dicalcium phosphate; wherein the formulation has an initial viscosity that ranges from about 40,000 centipoise to 370,500 centipoise. 2. The formulation of claim 1, wherein the formulation has an initial viscosity of from 47,800 centipoise to 370,500 centipoise. 3. The formulation of claim 1, wherein the formulation comprises 7 wt % of the lidocaine and 7 wt % of the tetracaine. 4. The formulation of claim 1, wherein the lidocaine and the tetracaine are present in the formulation at a weight ratio ranging from 2:1 to 1:2. 5. The formulation of claim 1, wherein the polyvinyl alcohol has an average molecular mass ranging from 20,000 daltons to 100,000 daltons. 6. The formulation of claim 1, wherein the polyvinyl alcohol has an average molecular mass ranging from 30,000 daltons to 80,000 daltons. 7. The formulation of claim 1, wherein the lidocaine and tetracaine comprise a eutectic mixture. 8. The formulation of claim 1, wherein the emulsifying agent is sorbitan monopalmitate. 9. The formulation of claim 1, wherein the emulsifying agent is sorbitan monostearate. 10. The formulation of claim 1, wherein the formulation is for application to a skin surface. 11. The formulation of claim 1, wherein the lidocaine and the tetracaine are each in their base form. 12. The formulation of claim 1, wherein the formulation has an increase in viscosity after 3 freeze-thaw cycles of 8 times or less the initial viscosity, each of the 3 freeze-thaw cycles being determined by placement of the formulation in an environment of -18.degree. C. to -22.degree. C. for a period of time of 48 hours followed by thawing of the formulation at room temperature (about 25.degree. C.) for a period of 48 hours. 13. The formulation of claim 1, wherein the formulation has an initial viscosity of at least 50,000 centipoise and has an increase in viscosity after 3 freeze-thaw cycles of less than 8 times the initial viscosity with a maximum viscosity of 1,500,000 centipoise, each of the 3 freeze-thaw cycles being determined by placement of the formulation in an environment of -18.degree. C. to -22.degree. C. for a period of time of 48 hours followed by thawing of the formulation at room temperature (about 25.degree. C.) for a period of 48 hours. 14. The formulation of claim 1, wherein the formulation has an initial viscosity of at least 50,000 centipoise and has an increase in viscosity after 3 freeze-thaw cycles of less than 5 times the initial viscosity with a maximum viscosity of 1,500,000 centipoise, each of the 3 freeze-thaw cycles being determined by placement of the formulation in an environment of -18.degree. C. to -22.degree. C. for a period of time of 48 hours followed by thawing of the formulation at room temperature (about 25.degree. C.) for a period of 48 hours.