3rd Conf Retro and Opportun Infect. 1996 Jan 28-Feb 1;:164. Unique
A randomized double-blind placebo-controlled study (Syntex 1654) of oral
ganciclovir for the prevention of cytomegalovirus (CMV) disease in 725
people infected with HIV showed that ganciclovir was associated with a
49% risk reduction for the development of CMV disease (log rank p less
than 0.0001). During oral ganciclovir prophylaxis, cultures of urine
(and occasionally blood and/or semen) were performed every 2 months. The
last isolate recovered from each patient after at least 90 days of
treatment was tested for ganciclovir susceptibility by a plaque
reduction assay. Sensitivity was defined as an IC50 less than or equal
to 6 micromolar, and resistance was defined as an IC50 greater than 12
micromolar. The average monthly prevalence of positive CMV cultures (90%
urine-source) during oral ganciclovir prophylaxis was 11 % compared with
46% for the placebo group. 2 of 39 isolates tested to date from 39
patients receiving ganciclovir for a mean of 251 days (range 112-564)
were resistant; 36 isolates were sensitive. All 10 control isolates from
patients receiving placebo for a mean of 313 days(range ll2-519)were
sensitive. The resistant isolates were obtained from urine cultures
after 9 and 10 months of ganciclovir (IC50's=35.8 micromolar and 14.0
micromolar,respectively); after approximately 4 additional months of
prophylaxis CMV retinitis was diagnosed in both patients and failed to
respond to intravenous ganciclovir. Conclusions: Oral ganciclovir
prophylaxis significantly decreased the rate of cytomegalovirus
excretion. The prevalence of ganciclovir resistance was low (less than
l%) after a mean of 8.3 months of prophylaxis. Resistant virus in two
patients was associated with later treatment failure.
Administration, Oral Antiviral Agents/ADMINISTRATION &
DOSAGE/*PHARMACOLOGY/ THERAPEUTIC USE Cytomegalovirus/*DRUG EFFECTS
Cytomegalovirus Infections/*PREVENTION & CONTROL Double-Blind Method
Drug Resistance, Microbial Ganciclovir/ADMINISTRATION &
DOSAGE/*PHARMACOLOGY/THERAPEUTIC USE Human Microbial Sensitivity Tests
Placebos ABSTRACT