Merck Protease Inhibitor Trial Seeks Persons with CD4 Count Under 50

Protocol 39, Merck's study of the protease inhibitor MK-639
in persons with CD4 count under 50, will recruit 420 patients
at 12 U.S. sites. Enrollment should start in June or July.
Other patients will be recruited in Canada, Australia,
France, Germany, and Switzerland, beginning in September. The
study will last six months; but after 12 weeks, certain
patients in the blinded study may switch to open label. After
the trial, there will be additional extensions if the drug is
generally well tolerated and shows biologic activity.

To enter the BLINDED portion of this study, patients need to
have taken AZT for at least six months, and not have taken
3TC. They will be randomly assigned to receive either MK-639
alone, AZT plus 3TC, or a combination of all three drugs.
They must discontinue treatment with AZT, ddC, ddI, and d4T
two weeks before the study begins, and cannot use rifampin
during the study.

Volunteers who have not taken AZT for six months, or who are
intolerant to AZT, or who have taken 3TC, may be eligible for
an UNBLINDED portion of the study, in which they will receive
open-label MK-639. Rifampin is permitted in this portion of
the study.

Additional entry criteria (for both portions of the study)
include being at least 18 years old, not being pregnant, not
having acute hepatitis, no prior use of protease inhibitors,
no use of investigational agents or immunomodulators within
30 days prior to the study, and no use of immunosuppressive
therapy within two weeks prior to the study. Also, the CD4
count must have been below 50 on two separate tests at least
a week apart. There are additional safety criteria based on
blood, urine, and other tests.

For more information about Protocol 39, call the Merck
protease inhibitor information line, 800/379-1332.