Medical Chronicle recently hosted a product webinar on the launch of Tavirant, highlighting it as a crucial alternative when necessary. Dr Kay Mahomed, the keynote speaker, provided an in-depth analysis of Tavirant, a product developed by Cipla, emphasizing its role as a first-line antiretroviral therapy (ART) option. 

To watch this webinar, go to: https://rb.gy/uc4a85 

Dr Mahomed discussed several factors that underline the importance of alternative ART options like Tavirant, particularly in the context of an ageing HIV-positive population and those with various comorbidities. Key issues include: 

• Ageing population: Increased incidence of comorbidities such as hypertension and diabetes mellitus
• Renal issues: Both inherent renal complications and those arising from HIV-associated nephropathy and certain medications
• Chemotherapy: For patients undergoing cancer treatment
• Medications: Interactions with drugs like Purbac, acyclovir, amphotericin B, kanamycin, and NSAIDs
• Acute and opportunistic infections:
  Such as osteoporosis and a history of fractures, especially in elderly and post-menopausal women.

Given these factors, Dr Mahomed stressed the importance of having alternative ART options that are safe, have minimal side effects or toxicity, and are suitable for various populations including children and adolescents. 

TDF vs TAF: Understanding the differences 

Dr Mahomed highlighted the differences between tenofovir disoproxil fumarate (TDF) and tenofovir alafenamide (TAF), both of which are key components in ART regimens. 

• Virological efficacy: Both TDF and TAF exhibit similar virological efficacy
• TDF: Dosage of 300mg, known for reduced dyslipidaemia
• TAF: Dosage of 25mg, a prodrug with 90% lower plasma concentration. It achieves four times higher levels in lymphocytes and hepatocytes, reducing proximal tubular toxicity and the risk of bone mineral density loss.

Clinical applications of TDF, ABC, and TAF 

Dr Mahomed provided guidance on the use of TDF, abacavir (ABC), and TAF based on patients’ glomerular filtration rate (GFR): 

• GFR >60: TDF is recommended
• GFR <60 and >30: TAF is preferred as an alternative to ABC, with the benefits of not requiring Hepatitis B surface antigen testing or human leukocyte antigen typing
• GFR <30: ABC is recommendedOsteoporosis: Patients with osteoporosis in the lumbar spine or femoral neck should consider TAF
• Adolescents and paediatrics: Considerations around pill size for ease of administration
• Cost: A factor in the selection of the appropriate regimen.

Personal observations 

Drawing from personal experience, Dr Mahomed shared insights on the successful use of Tavirant: 

1. Usage abroad: Tavirant has been employed as a first-line option with positive outcomes
2. Liver function: Patients with abnormal liver function tests switched from TEE (a combination of TDF, emtricitabine, and efavirenz) to TER (TAF, emtricitabine, and rilpivirine) without virological failure (VF) or significant side effects
3. Neurological side effects: Shift workers experiencing neurological side effects on TEE switched to TER, with no VF or side effects observed.
4. Long-term switch: All patients initially on TEE were switched to TER a decade ago, with sustained success and no VF or side effects.
5. Proactive switching: Emphasis on the importance of not waiting for renal issues to arise before switching to more suitable alternatives like TER.