MK-1439 shows promise in treatment-naive males with HIV
ATLANTA — An investigational inhibitor of the HIV-1 reverse transcriptase was effective and well tolerated in treatment-naive male patients with HIV in both a 25-mg and 200-mg dose, according to phase 1b data presented here.
For the double blind, placebo-controlled study, researchers randomly assigned 18 patients to one of three treatment regimens: 25 mg MK-1439 (Merck), 200 mg MK-1439 or placebo, administered once daily for 1 week. Tolerability, pharmacokinetics, viral resistance and antiviral activity were assessed.
After 1 week, patients were then given an antiretroviral standard of care for 10 days to suppress potential resistance development.
Similarities in pharmacokinetics were observed between HIV-infected patients and healthy controls at similar doses, according to the researchers. On day 7, mean difference in log10 HIV RNA copies/mL between 25 mg MK-1439 vs. placebo was –1.37, and –1.26 for 200 mg vs. placebo. Viral breakthrough was not observed after 7 days of monotherapy.
Adverse events were mild to moderate and were limited. However, newly acquired HCV infection occurred in one patient and was accompanied by elevated liver enzymes. This was unlikely to be related to MK-1439, according to the researchers.

Matt Anderson
“In the end, we found that the compound was very well tolerated,” Matt Anderson, PhD, of Merck, said here. “We have a study that is now enrolling into phase 2b, and I am hopeful it will be a success based on our phase 1 studies.”
For more information:
Anderson M. #100. Presented at: 2013 Conference on Retroviruses and Opportunistic Infections; March 3-6; Atlanta.
Disclosure: Anderson is an employee of Merck.