Cytodyn Expands Clinical Apps for Pro 140 Beyond HIV Therapy

CytoDyn Inc., a biotechnology company focused on the development of new therapies for combating human immunodeficiency virus (HIV) infection, announced that recent research data has expanded the potential clinical indications for PRO 140, now in Phase 3 for the treatment of HIV, to include certain inflammatory diseases, autoimmunity, transplantation and cancer.

"CytoDyn is proud to have developed the first self-injectable antibody for the treatment of HIV now at the Phase 3 stage," said Dr. Nader Pourhassan, President and CEO. "With this accomplishment in hand, the company can now move into clinical development on other non-HIV indications for PRO 140. The selection of GvHD as our next clinical program has been an ongoing effort without losing focus on HIV. We have already completed a Key Opinion Leader (KOL) conference on GvHD and are prepared to submit a protocol to the FDA within the next few months, under a new IND (Investigative New Drug application) for this indication."

The chemokine receptor, CCR5, is expressed on a variety of cells that play a central role in inflammatory responses. The receptor is activated by a chemokine mediator called CCL5, which has been shown to be a central figure in many inflammatory disease processes. Blocking the interaction of CCL5 with the receptor CCR5 is believed to be of therapeutic benefit.

The monoclonal antibody PRO 140 targets the chemokine receptor CCR5, binding to it in a way that prevents HIV from using it as an entry gateway without activating the immune function of the receptor. The company's recent research data indicate that PRO 140 also interferes with activation of the receptor by the mediator CCL5.

The company has selected a transplantation indication called Graft versus Host Disease (GvHD) as its first non-HIV clinical indication. Graft-versus-host disease (GvHD) is a complication that can occur after a stem cell or bone marrow transplant. With GvHD, the newly transplanted donor cells attack the transplant recipient's body.

GvHD may occur after a bone marrow or stem cell transplant in which an individual receives bone marrow tissue or cells from a donor. This type of transplant is called allogeneic. The new, transplanted cells regard the recipient's body as foreign. When this happens, the newly transplanted cells attack the recipient's body.

The CCR5 receptor, the target for PRO 140, is an important mediator of GvHD, especially in the organ damage that is the usual cause of death. The only approved CCR5 inhibitor, Maraviroc, is currently in a Phase 2 study in GvHD and results are expected in 2016.

CytoDyn believes that PRO 140 has significant advantages over Maraviroc in more favorable dosing and pharmacokinetics, less toxicity and side effects, and no direct stimulation (agonist activity) of the CCR5 receptor.

In the United States, in 2011, over 7,500 unrelated donor bone marrow transplants were performed and another 10,000 conducted outside the U.S. One-year survival is now approximately 60 percent with the most common causes of death being relapse or GvHD. The market in the U.S. is expected to reach $500 million in the next several years.

"The company has sponsored a research program over the past year gathering data to support the use of PRO 140 in non-HIV indications. The PRO 140 target is the key receptor in the activation and migration of cells of the immune system to sites of inflammation," said Dr. Denis R. Burger, Vice Chairman and Immunology Consultant. "The results of these studies give us confidence that PRO 140 can have a significant therapeutic benefit in several inflammatory diseases, with GvHD being our first clinical target."