Tenofovir alafenamide exhibits similar efficacy, safety to Viread in HBV
BARCELONA — Tenofovir alafenamide was safe and showed non-inferior efficacy rates to Viread in hepatitis B e antigen-positive patients, according to phase 3 study results presented in a general session at International Liver Congress.
“If patients want long-term therapy, I think [tenofovir alafenamide] is the better option,” Henry L-Y Chan, MD, director of the Digestive Disease Institute at The Chinese University of Hong Kong in China, said during his presentation.
Henry L-Y Chan
Chan and colleagues assigned 873 hepatitis B e antigen (HBeAg)-positive chronic HBV patients to a treatment regimen of either 25 mg of tenofovir alafenamide, (Gilead Sciences; n = 581) a prodrug of tenofovir, or 300 mg of Viread (tenofovir disoproxil fumarate, TDF; Gilead Sciences; n = 292) for 96 weeks. A quarter of patients were treatment-experienced, according to Chan’s presentation.
After completion of those 96 weeks, patients received open-label tenofovir alafenamide for 48 weeks. The primary endpoint of the study was the number of patients with HBV DNA less than 29 IU/ml by 48 weeks, to determine whether or not the efficacy of tenofovir alafenamide was non-inferior compared with TDF.
Patients treated with tenofovir alafenamide had an overall 63.9% virologic response rate compared with 66.8% in patients treated with TDF. Treatment difference was –3.6%, Chan said.
More patients treated with tenofovir alafenamide reached normal alanine aminotransferase levels compared with patients treated with TDF. In addition, patients who received tenofovir alafenamide also experienced less decline in hip and spine bone mineral density, and a smaller increase in serum creatinine compared with patients treated with TDF.
Rates of discontinuations (n = 30 for tenofovir alafenamide, n = 14 for TDF) due to treatment were comparable between the patient groups. Serious adverse events were also similar.
“In the resistance analysis at 48 weeks, no sequence changes were significantly different and no resistance was detected in either group,” Chan said.
Chan concluded: “Tenofovir alafenamide was safe and well-tolerated in hepatitis B e antigen-positive patients. Safety was improved, with less change in bone and renal parameters.”
In a press release from EASL, Tom Hemming-Karlsen, MD, PhD, EASL vice-secretary, said, “While tenofovir disoproxil fumarate is an effective treatment option for patients with chronic hepatitis B, we are pleased that this treatment … could provide patients with an equally effective, and yet safer, treatment option.” – by Melinda Stevens
Chan HLY, et al. Abstract GS12. Presented at: International Liver Congress; April 13-17, 2016; Barcelona.
Disclosure: Chan reports serving as a consultant and lecturer for Gilead Sciences. Please see the full abstract for a list of all other authors’ relevant financial disclosures.