Date:          May 16, 1996   

From:          Director, Center for Biologics Evaluation and Research

Subject:       Additional Recommendations for Testing Whole Blood, Blood
               Components, Source Plasma and Source Leukocytes for Antibody
               to Hepatitis C Virus Encoded Antigen (Anti-HCV)

To:            All Registered Blood and Plasma Establishments


On April 23, 1992, August 5, 1993, and August 19, 1993, FDA
issued memoranda to all registered blood and plasma
establishments, which provided recommendations for testing for
antibody to Hepatitis C Virus Encoded Antigen (anti-HCV). This
memorandum supplements those previous  memoranda by
transmitting additional recommendations for testing for
antibody to anti-HCV in blood establishments.  (See attached
recommendations.)

In a public meeting of the Blood Products Advisory Committee
(BPAC) on March 21, 1996, after review and discussion of the
relevant information available, concern was expressed that the
use of a supplemental test for anti-HCV that uses fewer
antigens than the screening test for anti-HCV may cause
uncertainties. In particular, the Committee discussed its
concern that the use of the Chiron RIBA HCV 2.0 Immunoblot
Assay (SIA) as a supplemental test for anti-HCV should not be
used for donor re-entry if the Ortho  HCV Version 3.0 ELISA
Test System was used as a screening test.  FDA has considered
the BPAC concerns and sets forth in the attached rcommendations
donor re-entry and counseling procedures that should be used in
this situation. 

According to the attached recommendations, the use of either
the Abbott HCV EIA 2.0 or the Ortho  HCV 2.0 ELISA Test System
to screen donor blood remains acceptable and no changes or
clarifications to previous FDA HCV recommendation memoranda are
needed. The Chiron RIBA 2.0 SIA would continue to be used as a
supplemental test for both donor counseling and re-entry
following screening with the latter assays.

Although this guidance document does not create or confer any
rights, privileges or benefits for or on any person, and does
not operate to bind FDA or the public, it does represent the
agency's current thinking with regard to determining donor
re-entry for donors who test repeatedly reactive when using the
Ortho  HCV Version 3.0 ELISA Test System.





Questions or comments concerning these recommendations may be
directed to the Laboratory of 
Hepatitis, Division of Transfusion Transmitted Diseases,
FDA/CBER, (HFM-325), 1401 Rockville Pike, Rockville, MD 20852;
Phone: (301) 827-3011; FAX: (301) 496-0338.







                         ______________________________
                         Kathryn C. Zoon, Ph.D.








Attachment: Additional Recommendations for Testing Whole Blood,
Blood Components, Source Plasma and Source Leukocytes for
Antibody to Hepatitis C Virus Encoded Antigen (Anti-HCV)

               
               













    Additional Recommendations for Testing for Antibody to
     Hepatitis C Virus Encoded Antigen (Anti-HCV)In Blood
                        Establishments

                         May 16 , 1996

On April 23, 1992, August 5, 1993, and August 19, 1993, FDA
issued memoranda to all registered blood and plasma
establishments, which provided recommendations for testing for
anti-HCV. Additional recommendations are listed below. 

1.   The use of either the Abbott HCV EIA 2.0 or the Ortho  HCV
2.0 Elisa Test System to screen donor blood remains
acceptable and no changes or clarifications to previous FDA
HCV recommendation memoranda are needed. The Chiron RIBA
HCV 2.0 SIA would continue to be used as the supplemental
test for these screening tests.

2.   When testing donor blood, the same version of the HCV
screening test, e.g., either 2.0   or 3.0, should be used for
all initial and duplicate repeat tests.

3.   For the purpose of determining re-entry to the donor pool,
donors who test repeatedly reactive using the Ortho  HCV
Version 3.0 ELISA Test System may not be reinstated as suitable
donors using the Chiron RIBA HCV 2.0 SIA as a supplemental test.
Such donors should be temporarily deferred pending the availability of
a licensed supplemental test  containing the NS5 antigen.

    The reason for this recommendation is that the Ortho  HCV
Version 3.0 ELISA Test System contains an antigen, NS5, which
is not part of the Chiron RIBA 2.0 SIA design.    Therefore,
until a supplemental test is licensed that includes the NS5
antigen, re-entry is not recommended.

     It is recommended, however, that samples from donors who
test repeatedly reactive with the Ortho  HCV 3.0 Version
ELISA Test System be stored at -20oC or colder until a
suitable Licensed supplemental test is available.

4.   For purposes of donor counseling and as a aid in
diagnosis, donors who test repeatedly   reactive using Ortho 
HCV Version 3.0 ELISA Test System may be tested using the
Chiron RIBA 2.0 SIA. However, caution should be exercised when
a negative Chiron   RIBA 2.0 SIA test result is obtained 
because this supplemental test does not detect    antibodies to
the NS5 region.

5.   FDA will notify blood establishments should a supplemental
test become available that is suitable in all cases for
the evaluation of donors who test repeatedly reactive using the
Ortho  HCV Version 3.0 ELISA Test System.