Precautions of Viread

1. Severe Acute Exacerbation of Hepatitis B After Discontinuation of Treatment

Discontinuation of anti-hepatitis B therapy, including tenofovir alafenamide fumarate tablets, may result in severe acute exacerbation of hepatitis B. Patients who discontinue tenofovir alafenamide fumarate tablets should be monitored closely with both clinical and laboratory follow-up for at least several months after stopping treatment. If appropriate, resumption of anti-hepatitis B therapy may be required.

2. Risk of HIV-1 Resistance in Patients with HBV and HIV-1 Coinfection

Due to the risk of development of HIV-1 resistance, tenofovir alafenamide fumarate tablets are not recommended for the treatment of HIV-1 infection alone. The safety and efficacy of tenofovir alafenamide fumarate tablets in patients with HBV and HIV-1 coinfection have not been established. Before initiating treatment with tenofovir alafenamide fumarate tablets, HIV antibody testing should be offered to all patients with HBV infection, and if the result is positive, an appropriate combination antiretroviral regimen recommended for patients with HIV-1 coinfection should be used.

3. New-Onset or Worsening Renal Impairment

Postmarketing cases of renal impairment (including acute renal failure, proximal renal tubulopathy (PRT), and Fanconi syndrome) have been reported with the use of TAF-containing products; although most cases had potential confounding factors that may have contributed to the reported renal events, these factors may also predispose patients to tenofovir-related adverse events [see Adverse Reactions (6.2)].

Patients taking tenofovir prodrugs who have impaired renal function, as well as patients taking nephrotoxic drugs (including nonsteroidal anti-inflammatory drugs), are at increased risk of renal-related adverse reactions [see Drug Interactions (7.2)].

Before initiating or switching to tenofovir alafenamide fumarate tablets, and during treatment with tenofovir alafenamide fumarate tablets on a clinically appropriate schedule, assess serum creatinine, estimated creatinine clearance, urine glucose, and urine protein in all patients. In patients with chronic kidney disease, also assess serum phosphorus. Discontinue tenofovir alafenamide fumarate tablets in patients who develop clinically significant decreases in renal function or evidence of Fanconi syndrome [see Adverse Reactions (6.1) and Use in Specific Populations (8.6)].

4. Lactic Acidosis/Severe Hepatomegaly with Steatosis

Lactic acidosis and severe hepatomegaly with steatosis, including fatal cases, have been reported with the use of nucleoside analogs, including tenofovir disoproxil fumarate (TDF), another tenofovir prodrug, alone or in combination with other antiretroviral drugs. Suspend tenofovir alafenamide fumarate tablets treatment in any patient who develops clinical or laboratory findings suggestive of lactic acidosis or pronounced hepatotoxicity (which may include hepatomegaly and steatosis even in the absence of marked transaminase elevations).