21 CFR § 660.4 - Potency test.

---
identifier: "/us/cfr/t21/s660.4"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "21 CFR § 660.4 - Potency test."
title_number: 21
title_name: "Food and Drugs"
section_number: "660.4"
section_name: "Potency test."
chapter_name: "FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES"
subchapter_number: "F"
subchapter_name: "BIOLOGICS"
part_number: "660"
part_name: "ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "21 U.S.C. 321, 331, 351, 352, 353, 355, 360, 360c, 360d, 360h, 360i, 371, 372; 42 U.S.C. 216, 262, 263, 263a, 264."
cfr_part: "660"
---


# 660.4 Potency test.

To be satisfactory for release, each filling of Antibody to Hepatitis B Surface Antigen shall be tested against the Reference Hepatitis B Surface Antigen Panel and shall be sufficiently potent to detect the antigen in the appropriate sera of the reference panel by all test methods recommended by the manufacturer in the package insert.

[40 FR 29711, July 15, 1975]