ODEFSEY – a new combination pill containing rilpivirine (Edurant – an existing NNRTI), TAF (tenofovir alafenamide), and FTC (Emtriva – emtricitabine) was registered in Australia by Gilead Sciences in October 2016, and has now become available (from 01 May 2017) on the Pharmaceutical Benefits Scheme (PBS) for patient co-payment subsidy.
Odefsey is a combination product containing tenofovir alafenamide (TAF) which is prodrug of tenofovir (TDF). The clinical dose of TAF is much lower than the clinical dose of TDF. TAF (25mg) is already available in a number of other treatments that contained the higher dose (300 mg) ‘TDF’, such as the change of Truvada to Descovy, and Stribild to Genvoya, and now Eviplera to Odefsey.
Odefsey has been compared with Atripla (TDF/FTC/EFV) in Study 1160, and with Eviplera (TDF/FTC/RPV) in study 1216, and results suggests its usefulness for ongoing treatment. Study 0109 also investigated switching to TAF-based Genvoya, from a range of existing other treatments. Studies for initial (starting) treatment have also suggested its usefulness, through Genvoya-associated and Rilpivirine-associated studies. Many of these studies have also shown that TAF-based formulations (such as within Odefsey) have less of an impact on bone mineral density and kidney function.
Odefsey should not be prescribed for people starting treatment with HIV viral loads greater than >100,000 (which can occur in early infection) as rilpivirine (contained in Odefsey) is not considered to be effective at such high viral loads.
Odefsey is taken as one pill, once a day, and has a low side effect profile. Odefsey is indicated for initial (starting) treatment or ongoing (continuing) treatment. Odefsey must be taken with food. If you are currently taking Eviplera (containing TDF) ask your doctor whether a switch to Odefsey (containing TAF) may be relevant for you.
Odefsey has not formally been tested in the following populations:
- people co-infected with hepatitis B virus – Gilead states that “the safety and efficacy of Odefsey have not been established in patients co-infected with HBV and HIV”.
- people aged 65 years or older – Gilead state that the dose level of Odefsey should be used with caution in this population, although Genvoya (containing TAF/FTC) based studies have shown no difference in safety or efficacy in the elderly (>65yo), but rilpivirine (a component of Odefsey) studies “did not include sufficient numbers of people aged 65 and over”.
- pregnant women – Gilead states that “Odefsey should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus”.