Temirazer Tablet (Tenofovir Disoproxil Fumarate 300mg and Emtricitabine 200mg)

Temirazer Tablet combines tenofovir disoproxil fumarate (TDF) 300 mg and emtricitabine (FTC) 200 mg, two nucleotide/nucleoside reverse-transcriptase inhibitors (NRTIs). Together they form a two-drug antiretroviral backbone. For HIV-1 treatment, TDF/FTC must be used with another fully active antiretroviral agent or as part of a complete regimen.

The same fixed-dose combination is also widely used for HIV pre-exposure prophylaxis (PrEP) in appropriately tested HIV-negative people, subject to the approved label and renal/bone assessment. Because both agents are active against hepatitis B virus, stopping them in a person with HBV can trigger severe hepatitis flares.

Temirazer Tablet is prescribed for:

• HIV-1 infection—In combination with antiretroviral drugs to control the viral infection.
  
• HIV prevention (PrEP)—In patients at high risk of contracting HIV infection who are HIV negative.
  
• Hepatitis B virus (HBV)—The combination of tenofovir disoproxil fumarate 300 mg with emtricitabine 200 mg has shown efficacy against HBV infection, but the treatment protocol will depend upon the individual patient's condition.

For treating HIV infection, the Temirazer Tablet is not taken as monotherapy but in combination with other HIV medications. For HIV prophylaxis, an HIV test needs to be performed before beginning the treatment to ensure that there is no pre-existing infection, and further HIV tests need to be performed during the treatment course. As the medication acts against both HIV and hepatitis B, stopping its use in individuals having an HBV infection can lead to severe consequences.

Both tenofovir and emtricitabine have to undergo metabolism before becoming biologically active. The resultant compounds block the reverse transcriptase of HIV, an essential enzyme that HIV uses in order to produce viral DNA. In doing so, they prevent the virus from replicating. They are also capable of inhibiting one of the enzymes needed for HBV replication.

• iPrEx: Daily oral tenofovir disoproxil fumarate 300 mg and emtricitabine 200 mg reduced HIV acquisition among adherent men who have sex with men and transgender women.
  
• Partners PrEP and other studies: Tenofovir disoproxil fumarate-containing PrEP regimens showed strong preventive efficacy when taken consistently.
  
• ART evidence: Tenofovir disoproxil fumarate 300 mg and emtricitabine 200 mg has been a widely validated NRTI backbone in combination ART.
  

Just like any other medication, the Temirazer Tablet is also associated with some side effects. Most of the side effects are minor and usually go away within some time. Here are some of the symptoms, including:

Common side effects

• Headache
  
• Nausea
  
• Diarrhoea
  
• Fatigue
  
• Abdominal discomfort
  
• Mild creatinine changes

Serious side effects

• Renal impairment/Fanconi syndrome
  
• Loss of bone mineral density
  
• Severe HBV flare after discontinuation
  
• Lactic acidosis/severe hepatomegaly (rare)
  

Important: Dose and regimen must be prescribed by the treating specialist. Tablet/vial strength is not necessarily the patient dose. Do not start, stop, split, combine or substitute treatment based on website information.

In case there is a skipped dose of the Temirazer Tablet, take the dose as soon as you remember it unless the time for the subsequent dose is close by. In that case, avoid taking the skipped dose and proceed as per your schedule. Do not consume two doses at once. Repeated skipping of doses can reduce the effectiveness of HIV treatment and may need medical consultation.

• It is important to test HIV and viral load to verify the HIV status and the efficacy of the treatment.
  
• It is important to test creatinine, eGFR, and urine to assess the functioning of the kidneys.
  
• Testing for hepatitis B virus (HBV) may be recommended prior to the start of PrEP or a change in HIV treatment.
  
• Bone health may be assessed in patients with increased risk of bone problems.
  
• Regular monitoring should include medication use and adherence, and STI screening in case of PrEP.
  

• Current TDF/emtricitabine (Truvada/reference) prescribing information https://www.gilead.com/-/media/736839e6330640e58f0d73f518c9abaf.ashx​
  
• CDC/WHO current PrEP guidance https://www.cdc.gov/hivnexus/hcp/prep/index.html​
  
• Grant RM, et al. iPrEx. New England Journal of Medicine https://pubmed.ncbi.nlm.nih.gov/21091279/​
  
• Baeten JM, et al. Partners PrEP. New England Journal of Medicine https://www.nejm.org/doi/full/10.1056/NEJMoa1108524​​