July 2012 

The approaching Quad (Stribild)

Gilead Sciences has developed a single tablet for HIV treatment that contains all of the following drugs:

  • elvitegravir – a new integrase inhibitor
  • cobicistat – a new drug whose purpose is to raise the concentration of elvitegravir in the blood
  • tenofovir – a nuke that is widely used and sold under the brand name Viread and also found in Truvada, Atripla and Complera
  • FTC – another nuke that is widely used and also found in Truvada, Atripla and Complera

The co-formulation of these four drugs—elvitegravir, cobicistat, tenofovir and FTC—has been nicknamed the Quad. This new co-formulation is meant to be taken as a once-daily regimen for the treatment of HIV infection by people who have not previously been treated.

Most drug companies first seek approval for the sale of their medicines in the United States. That country’s drug regulatory agency, the Food and Drug Administration (FDA), is expected to license the Quad by the end of this summer. Regulatory agencies in Canada, Australia and the European Union are also reviewing data on the Quad. Health Canada is expected to license the Quad in the autumn of 2012.

The FDA has compiled an analysis of the data submitted for the licensure of the Quad. In this issue of TreatmentUpdate we make use of that FDA analysis to bring to our readers in-depth information about the Quad’s effectiveness, with a particular focus on its safety. This latter point is particularly important because the Quad is not just another once-daily regimen in a pill; it contains two new medicines—elvitegravir and cobicistat—that will be used by HIV-positive people for many years. Moreover, Gilead is collaborating with other drug companies to co-formulate cobicistat with other anti-HIV drugs, such as the protease inhibitor atazanavir (Reyataz). Therefore, it is critical to be aware of the risks and benefits of the new drugs contained in the Quad.

— Sean R. Hosein