ViiV Healthcare announced the start of a phase III programme to support regulatory filings for a two-drug regimen of dolutegravir (Tivicay) and lamivudine (Epivir) as a treatment for HIV-1 infection in adults who have not received prior antiretroviral therapy.

The phase III programme comprises two identical studies (GEMINI 1 and 2) comparing a two-drug regimen of dolutegravir plus lamivudine with a three-drug regimen of dolutegravir plus the fixed-dose tablet tenofovir/emtricitabine (Truvada). The studies together will include approximately 1,400 men and women living with HIV and are being conducted at research centres in Europe, Central and South America, North America, South Africa and Asia Pacific.

HIV care is a long-term prospect for those living with the disease, requiring life-long adherence to treatment. Since the introduction of highly active antiretroviral therapy 20 years ago, HIV treatment regimens have predominantly included three antiretroviral drugs. ViiV Healthcare is looking to the future and exploring how HIV treatment could evolve to reduce drug exposure and improve treatment adherence, while maintaining the level of efficacy achieved with three-drug regimens.

John C Pottage, Jr, MD, chief scientific and medical officer, ViiV Healthcare, commented, “We believe the clinical profile for dolutegravir presents an important opportunity to investigate the possibility of first-line treatment of HIV with a two-drug regimen. With this ambitious phase III programme, we will explore whether this two-drug regimen can fundamentally change the existing HIV treatment strategy, reducing the number of medications and potentially streamlining treatment regimens for people living with HIV.”

The GEMINI trials are the third development programme undertaken by ViiV Healthcare to investigate a two-drug regimen for the treatment of HIV.

Each study is a randomised, double-blind study and will compare the safety, efficacy, and tolerability of a two-drug regimen of dolutegravir plus lamivudine administered once daily, against dolutegravir plus two nucleoside reverse transcriptase inhibitors (tenofovir/emtricitabine fixed-dose combination) administered once daily in HIV-1 infected adult subjects that have not previously received antiretroviral therapy.

Each study will include approximately 700 subjects who will be randomised 1:1 to receive dolutegravir plus lamivudine or dolutegravir plus tenofovir/emtricitabine fixed-dose combination. Both studies are designed to demonstrate the non-inferior antiviral activity of a dolutegravir plus lamivudine regimen to that of dolutegravir plus tenofovir/emtricitabine fixed-dose combination. The primary efficacy endpoint will be measured at week 48 and the study will continue to evaluate the long term antiviral activity, tolerability and safety of dolutegravir plus lamivudine through week 148.

Dolutegravir (Tivicay) is an integrase strand transfer inhibitor (INSTI) for use in combination with other antiretroviral agents for the treatment of HIV. Integrase inhibitors block HIV replication by preventing the viral DNA from integrating into the genetic material of human immune cells (T-cells). This step is essential in the HIV replication cycle and is also responsible for establishing chronic infection. Tivicay is approved in over 100 countries across North America, Europe, Asia, Australia, Africa and Latin America.
About lamivudine

Lamivudine is a nucleoside analogue used in combination with other antiretroviral agents for the treatment of HIV infection. Lamivudine is available in branded (Epivir) and generic forms.