F/TAF plus cobicistat-boosted PIs maintained virologic suppression in children with HIV

Treatment with emtricitabine/tenofovir alafenamide (F/TAF) and cobicistat-boosted atazanavir (ATV/c) or darunavir (DRV/c) maintained high rates of virologic suppression through 48 weeks in children living with HIV, based on two cohorts of the GS-US-216-0128 study presented at IAS 2025.

“Nucleoside/nucleotide reverse transcriptase inhibitors, [such as F/TAF], in combination with boosted protease inhibitors (PIs) are guideline-recommended regimens for the treatment of HIV-1 in children with intolerability or resistance to integrase strand transfer inhibitors,” said the researchers.

However, “in the paediatric population, efficacy and safety data are limited for cobicistat-boosted PIs, including boosted PIs in combination with F/TAF,” they noted.

Hence, the researchers conducted a phase II/III, multicentre, open-label, multicohort study involving children aged 2 to <12 years and weighing ≥14 to <40 kg with HIV. The participants were divided into two groups: cohort 2 (aged 6 to <12 years and weight of ≥25 to <40 kg; n=23) and cohort 3 (aged ≥2 years and weight of ≥14 to <25 kg; n=26). They were given F/TAF 200/25 mg or 120/15 mg (low dose), respectively, in addition to ATV/c or DRV/c.

Among participants with available data, virologic suppression (HIV-1 RNA <50 copies/mL) was achieved and maintained through week 48 by 100 percent of participants in cohort 2 and 96 percent in cohort 3. [IAS 2025, abstract TUPEB041]

Cohort 2 experienced a decrease in median CD4 count from 876 cells/µL at baseline to 785 cells/µL at week 48, while cohort 3 had a decline from 940 to 769 cells/µL over the same period.

On the other hand, CD4 percentages increased in both cohorts, from 36.2 percent to 38.7 percent in cohort 2 and from 34.8 percent to 37.4 percent in cohort 3.

According to the researchers, “absolute CD4 counts and percentages remained within the expected range of physiological fluctuations for this age group” at week 48.

As for safety outcomes, overall drug-related adverse events (DRAEs) occurred in 29–33 percent of cohort 2 and 27 percent of cohort 3.

Participants in cohort 2 did not experience any serious DRAEs, whereas two participants in cohort 3 had hyperbilirubinaemia.

However, those who received F/TAF plus ATV/c were more likely to discontinue treatment due to AEs in cohort 2 than in cohort 3 (29 percent vs 7 percent).

No deaths were reported in any treatment groups.

Furthermore, none of the treatment groups showed clinically significant changes in height, weight, BMI, bone mineral density, or estimated glomerular filtration rate from baseline to week 48, the researchers noted.

“Overall, in this 48-week analysis of children with HIV aged 2 to <12 years and weighing ≥14 kg to <40 kg, F/TAF in combination with ATV/c or DRV/c demonstrated favourable efficacy, safety, and acceptability,” said the researchers.

“These data support further evaluation of F/TAF in combination with ATV/c or DRV/c in children with HIV,” they added.