Foundations of ART Management in Heavily Treatment–Experienced Patients

Fostemsavir, a gp120 attachment inhibitor, is the other relatively recently approved drug in a new class. The BRIGHTE study was undertaken in highly treatment–experienced patients.^20,21 It consisted of 2 cohorts. The randomized cohort consisted of 272 people with 1 or 2 remaining antiretroviral classes, and these individuals were randomized to receive either fostemsavir (n = 203) or placebo (n = 69) with their failing regimen. The primary endpoint was mean reduction in HIV-1 RNA at 8 days. At Day 8, there was an approximate 0.8 log₁₀ reduction in HIV-1 RNA in those who received fostemsavir vs only 0.17 log₁₀ reduction in those who received placebo. Therefore, intrinsic potency was established. Both arms of this cohort went on to received fostemsavir 600 mg twice daily with an OBR.

The nonrandomized cohort who had no remaining classes on which to rely were given fostemsavir 600 mg twice daily plus OBR. These patients were allowed to take other investigational agents if any were available.

In the randomized cohort, 60% had HIV-1 RNA <40 copies/mL at Week 96.²² In the nonrandomized group, only 37% achieved this endpoint. As we saw with ibalizumab, these patients achieved high levels of virologic suppression despite the limited options available when they received a new drug in a new class.

Overall, the safety profile with fostemsavir was quite good. Adverse events were rare and mostly mild.^20,22