CCR5 Antagonist Shows Activity Against 4-Class Drug Resistant HIV-1 From Heavily Treatment Experienced Subjects

Washington-based CytoDyn Inc. today announced that a research paper entitled “Leronlimab (PRO 140) activity against 4-class drug-resistant HIV-1 from Heavily Treatment Experienced Subjects” has been accepted, peer-reviewed, and is available as a journal pre-proof on ScienceDirect.

The Leronlimab study was conducted as an in-vitro clinical study of 25 HIV-1-infected patients harboring a documented 4-class drug-resistance nucleoside reverse transcriptase inhibitors (“NRTIs”), non-nucleoside reverse transcriptase inhibitors (“NNRTIs”), protease inhibitors (“PIs”), and integrase strand transfer inhibitors (“INSTIs”) enrolled in the Italian PRESTIGIO Registry.

Significant findings from the study and observations from the authors include:

• Leronlimab maintained total activity in the presence of extensive resistance to the four main antiviral classes.
• Leronlimab IC50 did not appear significantly altered by previous or current exposure to maraviroc.
• In vitro, leronlimab and maraviroc have been reported to have synergistic activity, further corroborating the different mechanisms of the two drugs despite the same CCR5 target.
• In vitro susceptibility to leronlimab is not affected by extensive drug resistance and exposure to maraviroc.
• Leronlimab may have some advantages over maraviroc as a clinically valuable CCR5 antagonist, including lower toxicity, less drug-drug interaction issue, and less frequent dosing.
• Leronlimab can play a key role in subjects with minimal therapeutic options and CCR5-tropic virus.

“We would like to thank our Italian colleagues for understanding the importance of leronlimab in the treatment of HIV. This is further proof that leronlimab can benefit CCR5 tropic HIV patients, including those patients with multidrug resistance. HIV patients deserve the opportunity for multiple, effective treatment options,” stated CytoDyn’s Chief Medical Officer, Scott A. Kelly M.D., in a press release issued on January 10, 2022.

Leronlimab, among various potential applications, is a viral-entry inhibitor in HIV/AIDS.

It binds to CCR5, thus protecting healthy T cells from viral infection by blocking the predominant HIV (R5) subtype from entering those cells. Leronlimab does not work on other strains of HIV (for example, X4). However, R5 is the most dominant strain of HIV.

Five clinical trials have demonstrated leronlimab could significantly reduce or control HIV viral load in humans. In addition, the leronlimab antibody appears to be a powerful antiviral agent with fewer side effects and less frequent dosing requirements than currently used daily drug therapies.

CytoDyn is a late-stage biotechnology company located in Vancouver, WA, developing innovative treatments for multiple therapeutic indications using leronlimab, a novel humanized monoclonal antibody targeting the CCR5 receptor.