Successful Phase I Study of HIV Vaccine

Mymetics Corporation has announced that its innovative HIV-1 (Human Immunodeficiency Virus type 1) vaccine proved to be safe and well tolerated and demonstrated a high level of immunogenicity in a Phase I trial involving 24 healthy women.

Jacques-François Martin, CEO of Mymetics, commented: "Until the completion of this Phase I trial, the capacity of our HIV-1 vaccine to induce mucosal antibodies in the genital and rectal tracts of women was unknown. Preclinical studies in non-human primates generated extremely promising data demonstrating 100% protection against multiple intra-vaginal challenges with a live virus. These new results in female volunteers strongly confirm the validity of our approach and represent a major milestone for the development of a prophylactic HIV-1 vaccine capable of establishing an efficient front-line defense at the mucosal level."

All vaccinated women rapidly developed lipopeptide P1-specific serum antibodies, confirming the high efficacy of the influenza virosomes as carriers/adjuvants for inducing a Th2 (T helper type 2) response. All vaccinated subjects also developed lipopeptide P1-specific antibodies in vaginal and rectal secretions.

The functional antiviral activity of these mucosal antibodies was demonstrated by the inhibition of HIV-1 transcytosis, as reported by Dr. Morgane Bomsel (INSERM/Cochin Institute, France), a key academic partner.

"This study confirms the safety profile of virosomes and the promising anti-HIV-1 mucosal responses elicited by our MYM-V101 vaccine. We will now plan the next Phase I/II trials to test an additional HIV-1 antigen and a further optimized vaccine formulation. Mymetics will also continue its efforts to develop a vaccine formulation suitable for developing countries that is able to convey cross-clade protection," added Sylvain Fleury, Chief Scientific Officer of Mymetics.

"Although participation in the study necessitated repeated visits and examinations, many young women volunteered and the required number of volunteers was rapidly attained. The vaccine administrations and study procedures were well tolerated, leading to excellent compliance," said Prof. Leroux-Roels, Principle Investigator of the Mymetics trial from the Faculty of Medicine at the University of Ghent, Belgium.

Mymetics co-developed the current HIV-1 vaccine with its industrial partner Pevion Biotech, using proprietary virosome technology. The next trial will also involve the industrial partner Px-Therapeutics (Grenoble, France) for its expertise in recombinant protein production and GMP grade for clinical trials.

With its vaccine, Mymetics aims to provide a first line of defense through mucosal protection as well as a second line of defense against infection through the generation of blood antibodies. This Phase I study confirms Mymetics' previous pre-clinical study conducted on non-human primates, which was published in February 2011 in the journal Immunity. A larger study in non-human primates is currently planned.