Vonaday Tablet (Tenofovir Disoproxil fumarate (300mg) + Efavirenz (600mg) + Lamivudine (300mg))

Vonaday Tablet is a once-daily fixed-dose antiretroviral combination containing efavirenz 600 mg, lamivudine 300 mg and tenofovir disoproxil fumarate 300 mg. Efavirenz is an NNRTI; lamivudine and tenofovir are NRTIs. The three medicines suppress HIV at complementary points in reverse transcription.

Efavirenz 600 mg-based single-tablet regimens were widely used as first-line ART for many years. Current international guidelines often prefer integrase-inhibitor-based regimens such as dolutegravir because of improved tolerability and resistance profile, but efavirenz 600 mg tablet-based therapy remains an established alternative in selected settings.

Vonaday Tablet is prescribed for the treatment of:

• HIV-1 Infection
  

This fixed-dose combination is used for the treatment of HIV and is not indicated for PrEP due to the efavirenz tablet contained in this drug, which makes a full treatment regimen. The doctor reviews the resistance profile to HIV, renal function, presence of hepatitis B, pregnancy conditions, and other drugs used before taking this combination or when switching to this drug. Tenofovir isoproxil fumarate 300 mg and another NRTI in this combination are effective against hepatitis B; thus, withdrawal of the combination in those patients infected with hepatitis B may worsen the condition.

Efavirenz 600 mg tablet inhibits an enzyme known as HIV reverse transcriptase, which is required by HIV in replication of its genetic material. On the other hand, tenofovir disoproxil fumarate 300 mg tablets and lamivudine 300 mg tablets get metabolized in the body to form compounds that are analogous to nucleotides for viral DNA synthesis and prevent further replication of the viral genome.

Efavirenz-based ART trials: Clinical trials in large patients demonstrated that the efavirenz 600mg tablet with the two NRTIs was able to reduce the viral load of HIV. This made the efavirenz 600 mg-based treatment a valuable first-line treatment strategy previously.

Modern comparative trials: However, more recent research indicated that dolutegravir-based regimens have better resistance and tolerability profiles.

Vonaday Tablet side effects may be varied, depending on the dosage and patient reaction to the medication. Side effects can be managed, but some may need immediate medical attention. These include:

Common side effects

• Dizziness
  
• Vivid dreams or sleep disturbance
  
• Headache
  
• Nausea
  
• Rash
  
• Fatigue
  
• Difficulty concentrating

Serious side effects

• Severe psychiatric symptoms
  
• Severe skin reactions
  
• Hepatotoxicity
  
• Renal toxicity from TDF
  
• HBV flare after discontinuation
  
• QT prolongation in susceptible patients
  

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.

Take a missed dose when remembered unless close to the next dose. Do not double. Maintaining daily adherence is critical to avoid viral rebound and resistance.

• HIV viral load will help evaluate how the therapy is managing the infection.
  
• The CD4 count test may be performed when necessary to assess the status of the immune system.
  
• The kidney function must be evaluated because the tenofovir disoproxil fumarate tablet has an impact on the kidneys.
  
• The status of the liver needs to be assessed because the efavirenz 600mg tablet may lead to liver dysfunction.
  
• The hepatitis B virus (HBV) infection needs to be controlled, particularly in patients with HIV/HBV co-infection.
  
• Psychological and nervous system status needs to be evaluated, including mood disturbances, dizziness, confusion, and sleep disorders.
  

• Current efavirenz/tenofovir fixed-dose prescribing information as applicable https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=fc9c2149-8d40-401b-af13-5ae7f953950a​
• Current WHO/DHHS/IAS-USA HIV treatment guidelines https://www.iasusa.org/2025/04/08/hiv-drug-resistances-recommendations/​
• ADVANCE and other modern ART comparative trials for current regimen context https://pmc.ncbi.nlm.nih.gov/articles/PMC12617324/​​