Leronlimab (PRO 140) Advances as an HIV Combination Therapy Candidate

The makers of leronlimab (PRO 140) have filed the non-clinical portion of the drug’s Biologics License Application (BLA) as a combination therapy for HIV, the first of 3 sections of the submission, using the US Food and Drug Administration’s (FDA) Rolling Review process.

“This is the most important milestone yet in CytoDyn’s history,” Nader Pourhassan, PhD, president, CEO, and director of CytoDyn, the company developing PRO 140, said in a statement.

“We continue to execute on the submission of our BLA and are well positioned for potential revenue in 2020, subject to final approval. Our team is working diligently to complete the clinical and CMC portions, which represent the remaining two components of the BLA. We are also currently evaluating certain licensing opportunities relating to the commercialization of leronlimab upon approval.”

PRO 140, part of a new class of therapeutics called viral-entry inhibitors, is an investigational humanized IgG4 mAb that acts as a CCR5 antagonist to block the cellular receptors that investigators believe could play a pivotal role in HIV infection. It could ultimately be used as a combination therapy along with highly active antiretroviral therapy (HAART).

To date, leronlimab has been tested in more than 700 individuals across 9 phase 1/2/3 clinical trials, with phase 3 data showing success when used in combination with standard antiretroviral therapy (ART) in treatment-experienced patients with HIV. Participants demonstrated a significantly reduced or controlled HIV viral load on the drug.

The upside for patients is less frequent dosing requirements compared with daily drug therapies, as well as potentially fewer side effects.

A phase 3 investigative trial testing PRO 140 as a once-weekly monotherapy for patients with HIV is also underway.

“Clinical results to date from multiple trials have shown that leronlimab (PRO 140) can significantly reduce viral burden in people infected with HIV with no reported drug-related serious adverse events,” a CytoDyn statement reported. “Moreover, results from a Phase 2b clinical trial demonstrated that leronlimab (PRO 140) monotherapy can prevent viral escape in HIV-infected patients, with some patients on leronlimab monotherapy remaining virally suppressed for more than 4 years.”

CytoDyn also plans to initiate clinical trials to test PRO 140’s efficacy in a cancer setting and is currently conducting trials to test its efficacy in immune cell trafficking.