VIRxSYS Announces Interim Results from VRX496 Gene Therapy Phase II Trial

GAITHERSBURG, Md., Feb. 6 /PRNewswire/ -- VIRxSYS Corporation, a privately held company developing gene therapies for HIV and genetic diseases, presented results from its Phase II trial of VRX496, a gene therapy for the treatment of AIDS, at the 2008 Annual Conference on Retroviruses and Opportunistic Infections (CROI) in Boston, MA.

"This appears to be a significant demonstration of slowing and possibly halting the replication of the infectious HIV virus in humans," said Dr. Gary Blick, Medical Director, Circle Medical LLC. "VRX496 appears to cause wt-HIV particles to lose their envelopes and the in vivo pressure delivered by a patient's own modified cells leads to massive quasispecie reductions and production of impaired and less replicative virions. This treatment shows tremendous promise."

VRX496 has the potential to change HIV/AIDS care. Currently there are a variety of drugs available for HIV-infected patients, but all have long-term complications. To date, there have been no reported adverse events in any patient receiving VRX496 in clinical trials. In addition, VRX496 does not require daily administration.

"We are proving the effectiveness of our lentiviral vector approach in attacking HIV," said Dr. Laurent Humeau, VP of R&D for VIRxSYS. "Our lentiviral vector VRX496 appears to sustain expression of the RNA antisense targeting the HIV envelope for a long period of time, with a measurable effect on the HIV replicative fitness up to 3 years following a single injection. We believe this will prove to be an important step in the treatment of this disease."

VRX496 is a different viral vector than those used in previous gene therapy trials. VRX496 is derived from HIV-1 itself and has it disease-causing elements removed. Currently, VRX496 is being investigated as a therapeutic treatment (a treatment for those already infected with HIV). Unlike other viral vectors, lentiviral vectors appear to sustain expression of the delivered genes of interest for a longer period of time. Their safety profiles are currently being evaluated in clinical trials.

"These results are everything we've been hoping for," said Dr. Riku Rautsola, CEO and President of VIRxSYS. "VRX496 is a remarkably promising treatment for HIV. We are very excited about what we are seeing so far in our trials and are confident that these results will continue into Phase III."

The VIRxSYS results were presented at CROI on Tuesday, February 5th from 1-4 PM at session 124 in Hall A. The VIRxSYS poster was number 753.

About VIRxSYS

VIRxSYS is a private biotechnology company using proprietary lentiviral vector delivery and RNA payload platforms to develop therapies for serious human diseases. The Company's initial lentiviral delivery technology was exclusively licensed from The Johns Hopkins University and has been substantially advanced in the Company's laboratories. The RNA payload technology was acquired and has been integrated with the Company's lentiviral delivery technology. In addition to preclinical programs for genetic and other serious diseases, the Company is currently developing gene and vaccine therapies for HIV, one of which has advanced to Phase 2 human clinical trials. More information regarding VIRxSYS can be found at www.virxsys.com. Details for the Phase II study can be found at the NIH clinical trials website at clinicaltrials.gov/show/NCT00131560.

Contact: Paul Gibney

Phone: (212) 255-5340

E-mail: [email protected]

SOURCE VIRxSYS Corporation