By Colin Kellaher


Merck & Co. on Monday reported positive results from a Phase 1 study evaluating the safety, tolerability and pharmacokinetics of its investigational islatravir subdermal implant for the prevention of HIV-1 infection.

The Kenilworth, N.J., drugmaker said the data support the potential for a once-yearly dosing regimen for islatravir using a subdermal implant for pre-exposure prophylaxis, or "PrEP," of HIV-1 infection.

Merck said the implant achieved active drug concentrations above the pre-specified threshold at 12 weeks across the three doses of islatravir studied and is projected to provide drug concentrations likely above threshold for one year at the highest dose.

Based on the findings, Merck said it plans to launch a Phase 2 trial to further explore the potential of a subdermal implant containing islatravir as a long-acting option for PrEP for up to 12 months.

The company is studying islatravir across a variety of doses, formulations and frequencies for both the treatment of HIV-1 infection in combination with other antiretroviral agents and for the prevention of HIV-1 infection as a single agent.

Shares of Merck rose nearly 3% in midday trading Monday.


Write to Colin Kellaher at


(END) Dow Jones Newswires

March 08, 2021 12:17 ET (17:17 GMT)

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