Singapore: Gilead Sciences received complete response letters from the US FDA for its New Drug Applications (NDAs) for elvitegravir and cobicistat for use as part of HIV treatment regimens. In its communications, the FDA stated that it cannot approve the applications in their current forms.

The letters state that during recent inspections, deficiencies in documentation and validation of certain quality testing procedures and methods were observed. Gilead is working with FDA to address the questions raised in the complete response letters and move the applications forward.

Elvitegravir and cobicistat are also components of Gilead's once-daily single tablet HIV-1 regimen Stribild (elvitegravir 150 mg/cobicistat 150 mg/emtricitabine 200 mg/tenofovir disoproxil fumarate 300 mg), which was approved by FDA in August 2012 for treatment-naïve adults. This regulatory action does not affect the marketing authorization or continued use of Stribild.

Gilead submitted its NDAs for elvitegravir and cobicistat in June 2012. Marketing applications are also pending in Europe.