TAFER

Tenofovir alafenamide (TAF) instructions
Product name: TAF
Common name: tenofovir alafenamide
Dosage form: tablets
Packing: 30 tablets
Specification: 25 mg
Origin: India, Bangladesh

Product introduction
Tenofovir alafenamide (tenofovir Alafenamide (TAF) is an innovative, targeted new drug against hepatitis B virus. It is the first drug approved for the treatment of CHB in the past decade. TAF is a new type of nucleoside reverse transcriptase inhibitor that has been proven in clinical trials to have very high antiviral efficacy at a dose lower than one-tenth of Gilead's marketed drug tenofovir disoproxil (TDF). It can also improve renal function and bone parameters:

1. TAF has better bone safety for hepatitis B patients. Compared with the original hepatitis B drugs, TAF can effectively improve the bone safety coefficient and reduce the risk of osteoporosis. Under normal dosage, TAF compared with TDF caused a decrease in hip bone density of -0.29% vs -2.16%; a decrease in spine bone density of -0.88% vs -2.51%. TAF can greatly slow down the loss of bone density in patients with hepatitis B when taking medication.

2. At the same time, TAF has better renal safety. The decline in glomerular filtration rate (eGFR) is an important indicator for the diagnosis of chronic kidney disease, and its decline reflects the health of kidney function. In terms of the degree of decrease in eGFR (glomerular filtration rate) compared with baseline, TAF and TDF were 1.2 mL/min vs 5.4 mL/min.

Indications
Applicable to the treatment of adults with chronic hepatitis B (HBV) infection.

Usage and dosage
The recommended dose of TAF is 25mg/day, once a day.

Latest label update

Recently, the U.S. Food and Drug Administration (FDA) announced that it has approved an update to the label for Vemlidy (TAF, tenofovir alafenamide), adding the latest data on the long-term safety data of this hepatitis B drug and whether it interacts with the hepatitis C specific drug G4.

In the "Adverse Reactions" section of the instructions for TAF (tenofovir alafenamide), safety data for adult patients with chronic hepatitis B and compensated liver disease in Study GS-US-320-0108 and Study GS-US-320-0110 have been added. Analysis at week 96 showed that the most common adverse reaction was headache (occurring in ≥10% of patients). The proportion of patients who discontinued treatment with TAF (tenofovir alafenamide) or tenofovir fumarate (TDF) due to adverse reactions of any severity was 1.5% and 0.9%, respectively.

At Week 120, the safety profile of TAF (tenofovir alafenamide) was observed to be similar to that of patients who continued to receive the blinded treatment at Week 96. Additionally, the safety profile of patients who received TAF (tenofovir alafenamide) during the open-label phase was similar to that of patients who switched from TDF to TAF at week 96.

Latest safety data on changes in renal laboratory parameters and the impact on bone mineral density (BMD) have also been added to the package insert.

Pooled analysis showed that in the TAF (tenofovir alafenamide) group, the median change in eGFR from baseline to week 96 was -1.2 mL per minute, compared with -4.8 mL per minute in the TDF group. The mean percentage change in bone mineral density assessed by dual-energy X-ray absorptiometry (DXA) from baseline to week 96 also improved in the TAF (tenofovir alafenamide) group compared with the TDF group.

The revised labeling also increases the incidence of laboratory abnormalities (ALT, LDL-C, glycosuria, AST, creatine kinase, serum amylase) after taking TAF (tenofovir alafenamide) or TDF in Studies 108 and 110.

In addition, this revision also updates the drug interaction section, adding that: there is no clinically significant interaction between the hepatitis C specific drugs sofosbuvir/velpatasvir (the third generation of Gizumab) and sofosbuvir/velpatasvir/voxilaprevir (the fourth generation of Gizumab) and TAF (tenofovir alafenamide).