[Code of Federal Regulations] [Title 21, Volume 7] [Revised as of April 1, 2008] From the U.S. Government Printing Office via GPO Access [CITE: 21CFR660.43] [Page 128] TITLE 21--FOOD AND DRUGS CHAPTER I--FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) PART 660_ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS-- Subpart E_Hepatitis B Surface Antigen Sec. 660.43 Potency test. To be satisfactory for release, each filling of Hepatitis B Surface Antigen shall be tested against the Reference Hepatitis B Antiserum Panel and shall be sufficiently potent to be able to detect the antibody in the appropriate sera of the reference panel by all test methods recommended by the manufacturer in the package insert.