Two once-daily oral HIV-1 medicines have been approved by the Food and Drug Administration, according to Merck: Delstrigo, a fixed-dose combination tablet of doravirine (100 mg), lamivudine (300 mg), and tenofovir disoproxil fumarate (300 mg), and Pifeltro (doravirine, 100 mg). Both drugs are indicated for treating HIV-1 infection in adult patients with no prior antiretroviral treatment.
Pifeltro is a nonnucleoside reverse transcriptase inhibitor to be used in combination with other antiretroviral medicines. Delstrigo contains a boxed warning regarding posttreatment acute exacerbation of hepatitis B infection.
Delstrigo and Pifeltro are not curative, according to the announcement by Merck, which manufactures both drugs.
The FDA approval of Delstrigo was based on findings from the DRIVE-AHEAD trial (NCT02403674), which randomized 728 participants with no history of antiretroviral treatment to receive once daily either Delstrigo or efavirenz/emtricitabine/tenofovir disoproxil fumarate (EFV 600 mg/FTC 200 mg/TDF 300 mg). Delstrigo was associated with sustained viral suppression through 48 weeks, meeting its primary endpoint of noninferior efficacy when compared with EFV/FTC/TDF (84% vs. 81%, respectively), according to Merck.
Pifeltro was approved based on the results of the DRIVE-FORWARD trial (NCT02275780), which randomized 766 participants with no history of antiretroviral treatment to receive either Pifeltro once daily or darunavir 800 mg plus ritonavir 100 mg (DRV+r) once daily, each in combination with either emtricitabine (FTC)/TDF or abacavir (ABC)/lamivudine (3TC), as selected by the investigator. Pifeltro was associated with sustained viral suppression through 48 weeks, meeting its primary endpoint of noninferior efficacy when compared with DRV+r, each in combination with FTC/TDF or ABC/3TC (84% vs. 80%, respectively), according to the Merck announcement.