Janssen has launched REZOLSTA®, a new single tablet, once-daily, fixed-dose combination containing darunavir (marketed as PREZISTA®) and the pharmacokinetic enhancing or "boosting" agent cobicistat (marketed as TYBOST® by Gilead Sciences, Inc.), indicated for use in combination with other antiretroviral medicinal products for the treatment of human immunodeficiency virus-1 (HIV-1) infection in adults aged 18 years or older with no darunavir resistance-associated mutations.1 The availability of this treatment means that for the first time, patients are able to take darunavir, the UK's most prescribed protease inhibitor2, combined with a booster in only one tablet.
The availability of the darunavir/cobicistat combination treatment in the UK follows its authorisation by the European Medicines Agency (EMA), based on bioequivalence data for darunavir and cobicistat fixed-dose combination tablet versus single agents, and data evaluating the safety and efficacy of cobicistat-boosted darunavir.3-5 The data demonstrated that once-daily darunavir/cobicistat offers effective virological suppression over 48 weeks and that a high genetic barrier to resistance of darunavir is retained with the cobicistat booster.5,6
Professor Anna Geretti, Department of Virology & Infectious Diseases at the Institute of Infection & Global Health of the University of Liverpool, commented:
"The availability of this new formulation means that, for the first time, patients will be able to take a protease inhibitor and boosting agent once a day, in a single tablet, in combination with other required antiretroviral medicines. Reducing the pill burden in this way could increase patient adherence to treatment."
It is estimated that there are 100,000 people living with HIV in the UK and approximately 6,000 new diagnoses confirmed each year.7 Thanks to treatment advances over the past three decades, HIV is no longer considered a fatal illness in developed countries.8 However, adherence to treatment is essential in order to prevent low drug levels in the blood allowing the virus to become resistant to treatment.9 Evidence demonstrates that 39% of patients show less than 90% adherence to their treatment regimen10 and that after eight months of treatment, only 65% of patients achieve 100% compliance.9
Studies have shown that the once-daily, single tablet darunavir/cobicistat combination, demonstrates a similar tolerability profile to darunavir.3-5 The treatment was generally well tolerated over 48 weeks and only 5% of patients discontinued treatment due to adverse events.11
"Janssen is dedicated to improving the lives of all people living with HIV and the simplification of treatment regimens can be an important aspect of this. We believe this convenient 'one tablet, once daily' regimen will be a valuable addition to the options available to prescribers and, most importantly, to their patients," commented Peter Barnes, Medical Director at Janssen.
Janssen will continue to make darunavir available, as a single agent in tablets, so patients and their physicians can decide which HIV treatment regimen is best for them.
About Prezista® (darunavir)12
Darunavir is a protease inhibitor used for the treatment of human immunodeficiency virus (HIV-1) infection and can be taken with either ritonavir (indicated for use in adults and pediatric patients from the age of 3) or cobicistat (indicated for use in adults only). Darunavir received initial approval in Europe in 2007 for use in HIV-1 infected highly pre-treated patients, with later approvals for treatment-naïve and less experienced adult patients, and then for use in pediatric patients. Darunavir/ritonavir is approved for use in pediatric patients aged 3-17.
Tybost (cobicistat 150 mg tablets) is a cytochrome P450 3A (CYP3A) inhibitor. It boosts blood levels of atazanavir or darunavir by inhibiting CYP3A, an enzyme that metabolizes these drugs in the body. Cobicistat acts only as a pharmacokinetic enhancer and has no antiviral activity. Cobicistat was developed by Gilead Sciences Inc. and is a pharmacokinetic enhancer or boosting agent used with the protease inhibitors darunavir and atazanavir for the treatment of HIV, and is also found in STRIBILD® (elvitegravir / cobicistat / emtricitabine / tenofovir). Gilead Sciences Inc. is responsible for the manufacture, development and commercialization of cobicistat as a stand-alone product.