MEDICAL REVIEW

ADDENDUM

NDA No.: 20-386/SE1-028

DRUG NAME: COZAAR.... Tablets (Losartan Potassium)

SPONSOR: Merck & Co., Inc.

West Point, Pennsylvania 19486

TYPE OF DOCUMENT: New Drug Application-Efficacy Supplement

DATE RECEIVED: November 13, 2001

DATE REVIEW STARTED: January 10, 2002

DATE REVIEW COMPLETED: March 7, 2002

DATE REVIEW REVISED: April 1, 2002

MEDICAL REVIEWER: Juan Carlos Pelayo, M.D.

ERRATA

1. The statement in page 5:

… Hence, the retrospective nature of the subgroup analysis together with the lack of statistical

power for such analysis precludes any valid conclusion on the use of losartan in special populations.

should read:

… Hence, the lack of statistical power for a subgroup analysis precludes any valid conclusion

on the use of losartan in special populations.

2. The statement in page 7:

…Subgroup analysis of the primary endpoint by demographic variables or baseline factors is of

interest, but its retrospective nature together with the lack of statistical power preclude any valid conclusion

on the use of losartan in special populations.

should read:

… Subgroup analysis of the primary endpoint by demographic variables or baseline factors

is of interest, but the lack of statistical power precludes any valid conclusion on the use of losartan in

special populations.

3. The statement in page 24:

… The retrospective nature of the analysis in addition to the small number of patients in each

category per group precludes a valid commentary on the findings.

should read:

… The small number of patients in each category per group, i.e., the lack of statistical

power, precludes a valid commentary on the findings..---------------------------------------------------------------------------------------------------------------------

This is a representation of an electronic record that was signed electronically and

this page is the manifestation of the electronic signature.

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/s/

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Juan Carlos Pelayo

4/1/02 02:35:19 PM

MEDICAL OFFICER