The FDA announced revisions to the Viread label to include use in pediatric patients aged 2 years to less than 12 years with chronic hepatitis B based on 48-week safety and efficacy data.
Investigators administered Viread (tenofovir disoproxil fumarate, Gilead) in treatment-experienced patients during two randomized trials.
Trial 144 comprised 89 pediatric patients who received between 8 mg/kg and 300 mg of tenofovir disoproxil fumarate or placebo. At week 48, 77% of treated patients had HBV DNA less than 400 copies/mL compared with 7% of controls. Additionally, alanine aminotransferase normalization occurred in 66% of treated patients compared with 15% of controls.
The mean percentage of bone mineral density gains from baseline to week 48 in lumbar spine and total body was less in treated patients compared with controls. At week 48, the cumulative percentage of patients with 4% or higher decreases in spine or whole-body bone mineral density was numerically higher in treated patients than controls. The FDA noted that long-term bone health and fracture risks are unknown for pediatric patients.
In both Trial 144 and Trial 115, the investigators found no amino acid substitutions associated with resistance to tenofovir disoproxil fumarate among 14 of 15 patients who had HBV DNA of 400 copies/mL or higher posttherapy.