Virostatics Doses First Patient in Phase IIa Trial of VS411 for the Treatment of HIV Infection

SASSARI, Italy & PRINCETON, N.J.--(BUSINESS WIRE)--Virostatics, srl, a privately-held pharmaceutical company focused on the discovery and development of combination therapeutics in HIV/AIDS, virology, and other chronic diseases, today announced it has initiated dosing of subjects in its five-arm, dose-ranging, proof of principle study VS411-C201: A randomized double-blind dose-finding multi-centre Phase IIa study with VS411 for HIV-1 infection. Investigators in four countries, Italy, Russia, Uganda, and Argentina, will enroll 60 patients into five randomized blinded arms containing varying dosages of enterically-coated didanosine and hydroxyurea, the two components of VS411.

“In the RIGHT 702 study it was shown that a lower hydroxyurea dose of 600 mg daily achieved better antiretroviral activity than higher doses, together with better CD4+ cell count increases and fewer adverse effects”

"We are pleased to have reached this Phase IIa milestone with the dosing of our first subjects in Pavia, Italy," said Michael Stevens, PharmD and Chief Development Officer of Virostatics. “VS411 is the first once daily, combination product designed to not only directly target HIV replication but also to modulate the hyper-proliferation of CD4 T cells now believed to drive the progression to AIDS. We are honored to be working with our colleagues at the International Antiviral Therapy Evaluation Center (IATEC) and leading HIV researchers in Eastern and Western Europe, Africa, and the Americas to investigate this novel approach to the management of HIV disease.”

The combination of didanosine and hydroxyurea has been studied in many HIV-1 infected patients; however, these studies were performed with relatively high doses of 1000 to 1500 mg of hydroxyurea and 400 mg of didanosine per day, most often in combination with stavudine. VS411 has been designed to yield lower peak plasma concentrations of didanosine with improved dosing flexibility to investigate lower doses of hydroxyurea to further reduce toxicity and enhance efficacy. “In the RIGHT 702 study it was shown that a lower hydroxyurea dose of 600 mg daily achieved better antiretroviral activity than higher doses, together with better CD4+ cell count increases and fewer adverse effects,” said study investigator Renato Maserati, MD of Fondazione IRCCS Policlinico San Matteo in Pavia, Italy. “This innovative Phase IIa study will allow us to not only select the best dose to take forward into Phase IIb, but also to investigate to what extent the observed increase in antiviral efficacy and improved safety and tolerability of the VS411 combination may be due to the transition from cytotoxic to cytostatic effects at lower hydroxyurea concentrations.”

The VS411-C201 study will investigate hydroxyurea doses between 300 mg and 900 mg/day in combination with 200 mg or 400 mgs of enterically-coated didanosine administered over a four-week period using traditional measures of efficacy, pharmacokinetic parameters, safety, and tolerability. In addition, two non-traditional tests will be also used to further differentiate between the five arms. Intense intracellular pharmacokinetics will be performed to investigate the interaction between low dose hydroxyurea and the conversion of didanosine to its active form, dideoxyadenosine triphosphate, within CD4 cells and novel immunological tests will study the conservation of immune system cells with high proliferative capacity.

About Virostatics

Virostatics srl, an Italian pharmaceutical company with operations in Sassari and Pavia, Italy and Princeton, NJ, is committed to discovering and developing novel combination therapeutics to address significant medical needs in HIV/AIDS, chronic infections and related fields. The company is developing its lead product, VS411, as a fixed-dose combination of two drugs to not only decrease HIV replication but to also protect and conserve the immune system. VS411 has completed Phase I and has now begun a multinational Phase II development program. ViroStatics has developed a proprietary screening methodology to rapidly and efficiently identify cytostatic agents with potential to control the over-stimulation of the immune system that is believed to drive the progression of HIV to AIDS. Virostatics is committed to expanding its pipeline and product portfolio by in-licensing early- and late-stage compounds and exploring co-development opportunities that fit the Company's expertise in specialty pharmaceuticals and biopharmaceuticals in HIV/AIDS. For more information, visit Virostatics.com.