21 CFR § 640.55 - U.S. Standard preparation.

---
identifier: "/us/cfr/t21/s640.55"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "21 CFR § 640.55 - U.S. Standard preparation."
title_number: 21
title_name: "Food and Drugs"
section_number: "640.55"
section_name: "U.S. Standard preparation."
chapter_name: "FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES"
subchapter_number: "F"
subchapter_name: "BIOLOGICS"
part_number: "640"
part_name: "ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS"
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, 351, 352, 353, 355, 360, 371; 42 U.S.C. 216, 262, 263, 263a, 264."
regulatory_source: "38 FR 32089, Nov. 20, 1973, unless otherwise noted."
cfr_part: "640"
---


# 640.55 U.S. Standard preparation.

A U.S. Standard Antihemophilic Factor (Factor VIII) preparation may be obtained from the Center for Biologics Evaluation and Research, (HFM-407) (see mailing addresses in § 600.2 of this chapter) for use in the preparation of a working reference to be employed in a quality control potency test of Cryoprecipitated AHF.

[42 FR 21774, Apr. 29, 1977, as amended at 49 FR 23834, June 8, 1984; 50 FR 4140, Jan. 29, 1985; 55 FR 11013, Mar. 26, 1990; 70 FR 14985, Mar. 24, 2005]