MK-2048 is the Merck & Co. designation for a molecule in its pre-clinical drug discovery portfolio that is an integrase inhibitor-class of agent selected for development as a preventative treatment against HIV infection.[1] Its second generation integrase design was hypothesized to be superior to the first available integrase inhibitor, raltegravir, in that "MK-2048 has a dissociation half-life of 32 hours on wild-type integrase—more than four times that of raltegravir",[1][2] and its dissociation half-life against the important HIV integrase mutant N155H was on the same order of magnitude as that of raltegravir against wild-type virus. These findings led Merck representatives to suggest the possibility of "reduced susceptibility to resistance mutations" for the second generation drug.[1] MK-2048 has been investigated for use as part of a pre-exposure prophylaxis (PrEP) approach to the treatment of HIV infection;[3] however, the results of a 2015-2016 placebo-controlled human clinical trial[4] indicated no observed correlation between tissue-associated VCV and/or MK-2048 and the inhibition of HIV infection, limiting expectations for this compound's efficacy for such applications.[5] At the time of these reports, there was no indication of the time by which "MK-2048, or related compounds, [would] be ready for clinical trials".[1]
^Clinical trial number NCT02356302 for "Safety and Pharmacokinetics of Intravaginal Rings Containing Vicriviroc (MK-4176) and/or MK-2048" at ClinicalTrials.gov