V526

V526 is Merck's investigational **HIV-1 preventive vaccine** comprising replication-defective adenovirus serotype 5 and adenovirus serotype 6 vectors encoding near-consensus clade B HIV-1 **Gag, Pol, and Nef** antigens. The combined-vector approach was designed to induce HIV-specific cellular immune responses while potentially mitigating the effect of pre-existing immunity to a single adenovirus vector serotype. In the completed V526-001 Phase 1 trial in healthy HIV-seronegative adults, the regimen was administered intramuscularly on day 1 and at weeks 4 and 26; vaccine-induced ELISPOT responses were predominantly directed against Nef. ([journals.asm.org](https://journals.asm.org/doi/10.1128/cvi.00144-09))

Other names

MRKAd5+6 HIV-1 trigene vaccineMRKAd5+6 trigene vaccine