	US 12,133,862 B2
	Implantable pharmaceutical composition prepared from components consisting of calcium sulfate alpha-hemihydrate, vancomycin and gentamicin
Sean Sydney Aiken, Staffordshire (GB); Phillip Anthony Laycock, Staffordshire (GB); John Joseph Cooper, Staffordshire (GB); John Stephen Bratt, Staffordshire (GB); and Michael Christopher James Harris, Staffordshire (GB)
Assigned to BIOCOMPOSITES LIMITED, Staffordshire (GB)
Filed by Biocomposites Limited, Staffordshire (GB)
Filed on Jun. 16, 2022, as Appl. No. 17/842,689.
Claims priority of application No. 2108727 (GB), filed on Jun. 18, 2021.
Prior Publication US 2022/0401471 A1, Dec. 22, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. A61K 33/06 (2006.01); A61K 9/16 (2006.01); A61K 31/7036 (2006.01); A61K 38/14 (2006.01)

CPC A61K 33/06 (2013.01) [A61K 9/1682 (2013.01); A61K 31/7036 (2013.01); A61K 38/14 (2013.01)]

17 Claims

1. A pharmaceutical composition prepared from components consisting of:

a) 18.4 g pharmaceutical grade, phase pure calcium sulfate α-hemihydrate;

b) 500 mg of vancomycin hydrochloride; and

c) 240 mg of gentamicin sulfate, the gentamicin sulfate in the form of a solution;

wherein the calcium sulfate α-hemihydrate is prepared by first converting a source of pharmaceutical grade calcium sulfate dihydrate to soluble calcium sulfate anhydrite by hydrothermal treatment in suspension, and then converting the resulting soluble anhydrous calcium sulfate to calcium sulfate α-hemihydrate by:

i) adding the calcium sulfate dihydrate to a quantity of water in a water:calcium sulfate dihydrate ratio of 0.3:1-0.5:1 to form a suspension and autoclaving the suspension at 235-265° C. for 1-2 hours to dehydrate to form soluble anhydrite;

ii) allowing the soluble anhydrite to cool in the autoclave in suspension to rehydrate back to calcium sulfate dihydrate; and

iii) draining off excess water and autoclaving again at 110-150° C. for 1-2 hours to convert the rehydrated calcium sulfate dihydrate to calcium sulfate α-hemihydrate.