Successful viral suppression in a two-year-old child with human immunodeficiency virus infection treated with bictegravir/emtricitabine/tenofovir alafenamide

Abstract

Background. Adherence to antiretroviral therapy (ART) is a major challenge in pediatric human immunodeficiency virus (HIV) management, especially in young children due to medication formulation, administration difficulties, and psychosocial barriers. Single-tablet regimens (STRs) have been shown to improve adherence and viral suppression in adults and adolescents, yet their use in younger children remains limited. Bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) is an STR with a high genetic barrier to resistance, making it a promising option for pediatric patients with adherence difficulties. Case Presentation. We report a case of a 2-year-old girl with perinatally acquired HIV who experienced persistent viremia despite multiple ART regimens. The mother received zidovudine prophylaxis during delivery, and the infant was started on zidovudine (AZT) prophylaxis on the first day of life. The patient’s ART history included AZT monotherapy at birth, followed by combination therapy with lamivudine (3TC), lopinavir/ritonavir (LPV/r), and later tenofovir/emtricitabine (TDF/FTC) with dolutegravir (DTG). Despite these regimens, poor adherence related to medication administration difficulties and caregiver challenges contributed to persistent viremia. A multidisciplinary team approach was implemented to address adherence barriers. Given the patient’s ongoing virological failure and resistance mutations (L76V and V179E), off-label use of BIC/FTC/TAF (50mg/200mg/25mg) was approved. The dosage was adjusted based on weight, and medication administration was closely monitored. Within one month of treatment, HIV RNA levels significantly declined from 1,800,000 to 207 copies/mL. Viral suppression was maintained over subsequent three-month intervals, with HIV RNA levels of 35, 40, and 43 copies/mL, alongside immune recovery as indicated by increased CD4 counts. Conclusion. The successful off-label use of BIC/FTC/TAF in a treatment-refractory pediatric HIV case highlights its potential efficacy in young patients facing adherence challenges. Its high genetic barrier to resistance and favorable tolerability make it a promising option when standard therapies fail. Further research is needed to optimize pediatric ART strategies and expand access to STRs globally.