New HIV Drug Could Mean No More Pills, But Two Injections Per Week
A new HIV drug could mean the end of daily pills even sooner than expected. But it also would mean injecting yourself twice a week.
PRO 140, manufactured by Cytodyn, is an injectable antibody that already has shown complete viral supression for more than 10 months in two patients in phase II clinical trials. Because not all of the 21 patients in the trial received the drug at the same time, some only have demonstrated viral suppression for six months.
Cytodyn is a manmade antibody, not a synthetic drug, and so far has shown no toxicities.
HIV Equal listened in Friday afternoon on an investor update for the drug. While the presentation contained several “forward-looking statements,” which essentially can be described as speculation, the U.S. Food and Drug Administration (FDA) and National Institutes of Health (NIH) have shown confidence in PRO 140.
The FDA has given the drug fast-track designation, and the NIH has funneled more than $20 million toward research, including $8 million to test the drug in patients with substance abuse-induced adherence problems.
Use of the drug calls for patients injecting themselves with it twice weekly – once in each thigh. Cytodyn hopes to get its NDA (new drug application) to the FDA as early as November of next year. If approved it could become the first injectable antibody in the world to treat HIV, with potential revenues of $1 billion annually, investors were told Friday.
Phase III trials are set to begin soon in patients who have failed to achieve viral suppression with their current regimens. Cytodyn will be given a week to show efficacy. If the drug achieves a success threshold of about half of what it demonstrated in phase II in terms of viral suppression, the other half of the 300-person blinded placebo trial will be given the drug, too.
PRO 140 works as a viral entry inhibitor, meaning it actually blocks HIV from entering a cell. Most medications work by inhibiting the enzymes HIV needs to replicate once it gets inside the cell.
“The PRO 140 antibody appears to be a powerful antiviral agent leading to potentially fewer side effects and less frequent dosing requirements as compared to daily drug therapies currently in use,” the company declared in a news release.
The inventor of PRO 140, Dr. Paul Maddon, will be overseeing the phase III trials. “Maddon is a molecular virologist and immunologist who has made major contributions to our understanding of HIV entry and infection,” the news release stated. “As a graduate student at Columbia University, he isolated the gene encoding CD4 and demonstrated that CD4 serves as the primary receptor for entry of HIV into immune system cells. While at Progenics (another biotech company), Dr. Maddon and his collaborators discovered that a second receptor, CCR5, is also required for HIV entry. He led the discovery and development of PRO 140, a humanized monoclonal antibody to CCR5 designed to treat HIV infection.”