• At Week 96, 73.1 percent of the treatment group achieved viral suppression
• Previously reported - at week 48 DOR met its primary efficacy endpoint of non-inferiority compared to DRV+r
• PDUFA action date set for October 23, 2018

Merck (NYSE: MRK)  announced on 7/24/18 Week 96 results from the Phase 3 DRIVE-FORWARD clinical trial evaluating the efficacy and safety of doravirine (DOR), the company’s investigational non-nucleoside reverse transcriptase inhibitor (NNRTI), in combination with other antiretroviral agents, for the treatment of HIV-1 infection in adult patients with no prior antiretroviral treatment history (treatment-naïve). At Week 96, 73.1 percent (277/379) of the group treated with once-daily DOR achieved viral suppression as measured by the proportion of patients who achieved HIV-1 RNA of less than 50 copies/mL, compared to 66.0 percent (248/376) of the group treated with once-daily ritonavir-boosted darunavir (DRV+r) (treatment difference: 7.1%, 95% confidence interval: 0.5, 13.7). These study results were presented today as a late-breaking abstract at the 22nd International AIDS Conference (AIDS 2018) taking place July 23-27, 2018, in Amsterdam.

Previously, the findings at Week 48 demonstrated that once-daily DOR met its primary efficacy endpoint of non-inferiority compared to DRV+r, each in combination with emtricitabine/tenofovir disoproxil fumarate (FTC/TDF) or abacavir/lamivudine (ABC/3TC). These data were presented at the Conference on Retroviruses and Opportunistic Infections in 2017.

“These Week 96 data reinforce the efficacy and safety of doravirine found at 48 weeks, and support the potential use of doravirine in the clinic as an important new treatment option for people living with HIV-1,” said Professor Chloe Orkin, lead for HIV and HIV/Hep C research, Ambrose King Centre, Royal London Hospital.

Doravirine (DOR) is an investigational NNRTI being evaluated by Merck for the treatment of HIV-1 infection. DOR is being evaluated in several ongoing clinical trials both as a once-daily single-entity tablet in combination with other antiretroviral agents in a tailored regimen, and as a once-daily fixed-dose combination (DOR/3TC/TDF) in a complete single tablet regimen. Phase 3 trials include DRIVE-FORWARD, a trial comparing DOR to once-daily ritonavir-boosted darunavir (DRV+r), each administered in combination with FTC/TDF or ABC/3TC, in treatment-naïve adults; DRIVE-AHEAD, a trial comparing DOR/3TC/TDF to efavirenz (EFV)/FTC/TDF in treatment-naïve adults; and DRIVE-SHIFT, a trial evaluating a switch to DOR/3TC/TDF in HIV-1 infected adults who are currently virologically suppressed on another antiretroviral regimen. Other ongoing Phase 2 clinical trials include an evaluation of DOR/3TC/TDF in treatment-naïve adults with transmitted resistance to NNRTIs and in people switching from EFV due to intolerability.

Earlier this year, the U.S. Food and Drug Administration (FDA) accepted for review New Drug Applications for DOR and DOR/3TC/TDF for the treatment of HIV-1 infection in treatment-naïve adults. The FDA has set a target action date of October 23, 2018 for both applications.