Effectiveness of enfuvirtide in a cohort of highly antiretroviral-experienced HIV-1-infected patients in Mexico

Background: Treatments in patients with multidrug resistance often involve the use of multiple agents with partial antiviral activity and overlapping metabolic toxicities. Enfuvirtide is therefore a welcome addition to the antiretroviral management of patients with multiclass resistant virus, given the low risk of systemic toxicities and novel mechanism of action relative to existing drug classes. Methods: Prospective cohort of treatment-experienced HIV-1-infected adults with virological failure who started therapy with an ENF-containing regimen. The effectiveness of ENF treatment was evaluated with percentages of undetectable HIV-1 RNA viral load after 24 and 48 weeks of treatment, and changes in CD4+ cell counts. Results: Forty patients >18 years were included. After 24 weeks of treatment, 91% of patients had HIV-1 RNA viral load <400 copies/mL and 65.8% had <50 copies/mL. At week 48 of treatment, 81.4% of the patients had HIV-1 RNA <400 copies/mL and 55.5% had <50 copies/mL; in both cases p <0.0001 compared to baseline. Increase CD4+ cells were also statistically significant at weeks 24 and 48 with respect to the baseline. Pain at the site of injection was the main adverse event in 100% of patients. Conclusion: Our study provides clinically important evidence of the effectiveness and safety of ENF in highly ARV-experienced HIV-1-infected patients. These findings strengthen the results of previous randomized controlled trials with this agent.