Claims for Patent: 4,742,158

Summary for Patent: 4,742,158

Title:	Purification of hepatitis pre-S antigens by polymerized serum albumin affinity binding
Abstract:	Recombinant pre-S-HBsAg is purified by a rapid and efficient two step chromatographic process. Yeast cells expressing recobinant pre-S-HBsAg are disrupted, the cell contents are clarified and separated by polymerized human serum albumin affinity chromatography. The pre-S-HBsAg is further purified by hydrophobic interaction chromatography using butyl agarose. This process results in pre-S-HBsAg that is greater than 90% pure.
Inventor(s):	Lehman; E. Dale (Lansdale, PA), Schaefer; Ted F. (Collegeville, PA), McAleer; William J. (Ambler, PA)
Assignee:	Merck & Co., Inc. (Rahway, NJ)
Application Number:	07/045,792
Patent Claims:	1. A method of purifying recombinant expressed hepatitis B virus pre-S surface antigens comprising: a. attachment of pre-S(2) containing antigen to a polymerized serum albumin matrix; b. elution of the antigens from the matrix with a salt formed by an alkali metal and a halogenated acetic acid; and c. final purification of the antigens using butyl agarose affinity chromatography and an acceptable eluant. 2. A method according to claim 1, step a, wherein the albumin is human or chimpanzee serum albumin. 3. A method according to claim 1, step a, wherein the albumin is human serum albumin. 4. A method according to claim 1, step a, wherein the antigen is pre-S(2)-HBsAg, pre-S(1)S(2)-HBsAg, pre-S(1)S(2) or pre-S(2). 5. A method according to claim 1, step b, wherein the alkali metal is lithium, sodium or potassium. 6. A method according to claim 4 wherein the alkali metal is sodium. 7. A method according to claim 1, step b, wherein there is one, two or three molecules of the halogen. 8. A method according to claim 1, step b, wherein the halogenated acetic acid contains three molecules of fluorine, chlorine, bromine, or iodine. 9. A method according to claim 1, step b, wherein the alkali metal salt of the halogenated acetic acid is trichloroacetate.

Details for Patent 4,742,158

Applicant	Tradename	Biologic Ingredient	Dosage Form	BLA	Approval Date	Patent No.	Expiredate
Grifols Therapeutics Llc	ALBUKED, PLASBUMIN-20, PLASBUMIN-25, PLASBUMIN-5	albumin (human)	For Injection	101138	10/21/1942		2006-04-25
Baxalta Us Inc.	BUMINATE, FLEXBUMIN	albumin (human)	Injection	101452	03/03/1954		2006-04-25
Csl Behring Ag	ALBURX	albumin (human)	Injection	102366	07/23/1976		2006-04-25
Grifols Biologicals Llc	ALBUTEIN	albumin (human)	Injection	102478	08/15/1978		2006-04-25
Instituto Grifols, S.a.	HUMAN ALBUMIN GRIFOLS	albumin (human)	Injection	103352	02/17/1995		2006-04-25
Instituto Grifols, S.a.	HUMAN ALBUMIN GRIFOLS	albumin (human)	Injection	103352	06/11/2003		2006-04-25
Csl Behring Llc	ALBUMINAR, ALBUMINAR-20, ALBUMINAR-25, ALBUMINAR-5	albumin (human)	Injection	103955	03/17/2000		2006-04-25