[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: 21CFR660.25]

[Page 122-123]
 
                        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 C_Blood Grouping Reagent
 
Sec. 660.25  Potency tests without reference preparations.

    Products for which Reference Blood Grouping Reagents are not 
available shall be tested for potency by a method approved by the 
Director, Center for Biologics Evaluation and Research.
    (a) Potency requirements. Blood Grouping Reagents recommended for 
the test tube methods, including the indirect antiglobulin tests, shall 
have the following potency titer values, unless other values are 
approved by the Director, Center for Biologics Evaluation and Research.
    (1) For Anti-K, Anti-k, Anti-Jk a, Anti-Fy a, 
Anti-C w, at least 1+ reaction with a 1:8 dilution of the 
reagent.
    (2) For Anti-S, Anti-s, Anti-P1, Anti-M, Anti-I, Anti-e 
(saline), Anti-c (saline), and Anti-A1, at least 1+ reaction 
with a 1:4 dilution of the reagent.
    (3) For Anti-U, Anti-Kp\a\, Anti-Kp\b\, Anti-Js\a\, Anti-Js\b\, 
Anti-Fy\b\, Anti-N, Anti-Le\a\, Anti-Le\b\, Anti-Lu\a\, Anti-Lu\b\, 
Anti-Di\a\, Anti-M\g\, Anti-Jk\b\, Anti-Co\b\, Anti-Wr\a\, and Anti-
Xg\a\, at least 2+ reaction with undiluted reagent.
    (b) Products recommended for slide tests or microplate techniques. 
Blood Grouping Reagent recommended for slide test methods or microplate 
techniques shall

[[Page 123]]

produce clearly positive macroscopic results when both undiluted reagent 
and reagent diluted with an equal volume of diluent are tested by all 
methods recommended in the manufacturer's package insert using red blood 
cells showing heterozygous or diminished expression of the corresponding 
antigen. The dilution shall be made with an equal volume of compatible 
serum or approved diluent.
    (c) Products recomended for use in an automated system. The 
manufacturer of Blood Grouping Reagent that is recommended for use in an 
automated system shall demonstrate that its product when used both 
undiluted and diluted with an equal volume of diluent satisfactorily 
performs when tested with cells representing heterozygous or diminished 
expression of the corresponding antigen.

[53 FR 12764, Apr. 19, 1988, as amended at 67 FR 9587, Mar. 4, 2002; 70 
FR 14985, Mar. 24, 2005]