Ray of Hope at International AIDS Conference
July 16 2004
New Zealand Sheds Ray of Hope at International AIDS Conference
Virionyx Corporation Ltd, the New Zealand biopharmaceutical firm that is developing a promising new treatment for late-stage AIDS, provided a ray of hope at the XV International AIDS Conference in Bangkok, Thailand, yesterday.
As the conference delegates grappled with the announcement that a preventative AIDS vaccine is still years away and with the United Nations report that 14,000 people are infected with human immunodeficiency virus (HIV) every day, the Auckland based company had some good news for them.
Virionyx told the doctors, researchers, scientists, medical professionals and media attending the conference that AIDS and HIV infected patients participating in the pre-Phase II multi dose clinical trials of its biotherapeutic, PEHRG214, at Harvard Medical School are responding favourably to treatment.
The international AIDS and cancer specialist, Associate Professor Bruce Dezube, who is conducting the trials, reported early signs of efficacy in the patients and that they generally tolerated the treatment well, in contrast to the existing AIDS drugs which have significant adverse side effects.
“The only adverse event was a rash – a mild allergic reaction – to the treatment in some of the patients. This was successfully prevented with Benadryl, Tylenol and Allegra on the days they were infused,” he said.
Despite the low dosage levels of PEHRG214 used in the trials, Dr Dezube said many patients showed significant improvement in three vital areas – a reduced amount of virus overall, an increase in the number of healthy CD4 white cells and a reduced number of infected white cells, which are the source of continuing infection in an HIV infected patient.
In his written summary of the trials for the conference, Dr Dezube said immune-based therapies, such as PEHRG214, may work to enhance conventional AIDS drug regimens or even play a key role in maintenance strategies that may eventually allow patients to stop taking drugs.
Back in New Zealand at the Virionyx Corporation laboratories Dr Frank Gelder, the company’s Scientific Director who discovered the proprietary antibody therapy preparation, said he was pleased that the United States Food and Drug Administration (FDA) approved trials on over 40 patients at Harvard and elsewhere were reinforcing and extending the results previously observed with the drug in the compassionate release treatment of 77 patients, some of them in New Zealand, in the late 1990s prior to it entering the formal FDA trial process.
Dr Gelder explained that PEHRG214 is a new approach to AIDS treatment, using antibodies purified from immunised goat plasma to target specific parts of the HIV not recognised by the human immune system.
He said Virionyx maintains two special herds of goats that it uses to produce antibodies against HIV. These antibodies are then formulated by Virionyx’s team of scientists for use in humans.
“Goats have immune systems that can recognise specific parts of HIV not recognised by the human immune system and mount an antibody response to these previously unidentified targets,” Dr Gelder said. “I developed the science for this in the US and brought it to New Zealand because of the unique environment in this country where livestock herds carry a very low incidence of chronic endemic diseases, especially those with potential to transfer to man, and can therefore be utilised to develop antibodies.”
Dr Gelder said under laboratory conditions PEHRG214 demonstrates the ability to destroy cell-free viruses.
“While currently available anti-HIV drugs taken in careful combination are very effective in controlling the ability of the virus to replicate and infect healthy CD4 white cells, sooner or later the virus mutates and escapes these treatment regimens. Trial data to date suggests PEHRG214 is effective even in patients who are failing the highly active anti-retroviral treatments known as HAART,” he said.
Based on advice from Dr Dezube and other international consultants assisting with the trial of PEHRG214, the drug will now immediately proceed to a full US FDA compliant Phase II efficacy trial in 40 patients.