In a statement, the Vancouver-based company said HIV-infected patients received 350 mg, 525 mg, or 700 mg of leronlimab once a week with 150 patients showing “sustained viral suppression” after a year of monotherapy.
Separately, the rate of viral load suppression after 10 weeks of monotherapy was 68%, 94%, and 85% respectively for HIV-infected patients on a 350 mg, 525 mg, and 700 mg drug dose regimen.
“The failure criteria after 10 weeks was three increasing viral loads over 50 cp/mL, or one viral load over 1000 cp/mL,” said the company in a statement.
READ: CytoDyn finalizes key test which will guide discussions with FDA on lead drug leronlimab as a monotherapy
CytoDyn CEO Nader Pourhassan commented: "These results position us well for our upcoming face-to-face meeting with the Food and Drug Administration regarding our pivotal monotherapy trial protocol.”
CytoDyn has been granted an in-person meeting with the FDA to discuss its pivotal Phase 3 monotherapy protocol that could lead to label expansion approval should leronlimab have its first approval as a combination therapy.
The company said over 110 HIV patients on leronlimab monotherapy for almost one year and five patients from the company’s original Phase 2 monotherapy extension have now reached almost five years without viral breakthroughs.
"Even more impressive is the long-term durability of the antiviral response in some patients in our other trials, with six patients reaching three years successfully on monotherapy and another four patients nearing the five-year mark for suppressed viral load," said Pourhassan.
Combatting pill fatigue
The CEO said a monotherapy with leronlimab, if approved, may allow patients with 'pill fatigue to maintain a disciplined compliance regimen.'
In the HIV and AIDS setting, leronlimab acts as a viral-entry inhibitor; it masks CCR5, thus protecting healthy T cells from viral infection by blocking the predominant HIV (R5) subtype from entering those cells.
In June, the company announced the development of a receptor occupancy test to measure the expression of CCR5 in HIV and tumor cells that are occupied by leronlimab.
In layman’s terms, a receptor occupancy assay measures the degree to which the test drug occupies its target receptor in tissues.
Pourhassan said that "recent data suggests that the receptor occupancy test being finetuned by Dr Bruce Patterson may effectively identify potential responders to monotherapy at the time of screening, thereby potentially raising the success rate in the monotherapy program.”
To date, over 830 HIV patients have participated in clinical trials with leronlimab (PRO140), including over 600 patients in ongoing and previous monotherapy trials. There have been no drug related serious adverse events reported in any of the HIV patients treated with leronlimab, the company noted in its statement.
Contact Uttara Choudhury at [email protected]
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