CytoDyn Injects First Patient in Its Current Phase III Study

CytoDyn Inc. recently announced that the first patient in its Phase III clinical trial has been injected with PRO 140, the company’s monoclonal antibody for the treatment of HIV. PRO 140 is the first self-injectable antibody in a Phase III protocol involving 300 HIV patients that will each be evaluated over a 25-week period.

The company believes that upon successful completion of this Phase III study, CytoDyn will have the opportunity to seek accelerated approval based on previously FDA-granted fast-track candidate designation.

Additionally, CytoDyn intends to apply for a breakthrough designation for PRO 140, as the first self-injectable antibody for HIV monotherapy for patients with resistance issues to the current standard of care, referred to as HAART (Highly Active AntiRetroviral Therapy).

The company’s recently completed Phase IIb treatment substitution trial demonstrated that 98% of patients treated with PRO 140 successfully passed 4 weeks of monotherapy without virologic failure. At the completion of the study some of these patients were offered the option to continue in an extension trial. CytoDyn recently announced that the first group of patients in the extension trial passed 1 year of monotherapy with complete viral load suppression. Currently, 11 patients are in the extension trial, and all 11 have now passed 1 year of monotherapy with PRO 140.

The company’s first Phase III trial is designed to allow PRO 140 as a component of a HAART regimen for treatment experienced patients. Management believes the market size for a HAART therapy, which includes the PRO 140 antibody, along with other PRO 140 indications, could exceed $1 billion dollars. CytoDyn believes that its PRO 140 antibody has compelling advantages over other approved drugs on the market for HIV. These advantages include less toxicity, fewer side effects, and once-a-week versus daily administration, which together may improve patient compliance.

“We are very pleased to have moved so quickly from completion of our Phase IIb clinical trial to the formal initiation of our Phase III licensing trial with the injection of the first patient with PRO 140,” said Dr. Nader Pourhassan, President and CEO of CytoDyn.

PRO 140 belongs to a new class of HIV/AIDS therapeutics (viral-entry inhibitors) that are intended to protect healthy cells from viral infection. PRO 140 is a fully humanized IgG4 monoclonal antibody directed against CCR5, a molecular portal that HIV uses to enter T-cells. PRO 140 blocks the predominant HIV (R5) subtype entry into T-cells by masking this required co-receptor, CCR5. Importantly, PRO 140 does not appear to interfere with the normal function of CCR5 in mediating immune responses. PRO 140 does not have agonist activity toward CCR5 but does have antagonist activity to CCL5, which is a central mediator in inflammatory diseases. PRO 140 has been the subject of seven clinical trials, each demonstrating efficacy by significantly reducing or controlling HIV viral load in human test subjects. PRO 140 has been designated a “fast track” product candidate by the FDA. 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.

CytoDyn is a biotechnology company focused on the clinical development and potential commercialization of humanized monoclonal antibodies for the treatment and prevention of Human Immunodeficiency Virus (HIV) infection. The company has one of the leading monoclonal antibodies under development for HIV infection, PRO 140, which has finished Phase II clinical trials with demonstrated antiviral activity in man and is currently in Phase III. PRO 140 blocks the HIV co-receptor CCR5 on T-cells, which prevents viral entry. Clinical trial results thus far indicate that PRO 140 does not negatively affect the normal immune functions that are mediated by CCR5. Results from six Phase I and Phase II human clinical trials have shown that PRO 140 can significantly reduce viral burden in people infected with HIV. A recent Phase IIb clinical trial demonstrated that PRO 140 can prevent viral escape in patients during several weeks of interruption from conventional drug therapy. CytoDyn intends to continue to develop PRO 140 as a therapeutic anti-viral agent in persons infected with HIV. For more information, visit