04 Aug 2006

New Aids patch offers hope

Patches have been used for years to help smokers kick the habit. Now a team of Hungarian and US researchers is looking to use the same technology to deliver a vaccine against HIV/Aids by as early as 2009.

Genetic Immunity, the company developing the vaccine, has just completed the first safety trials on humans in the Szent Laszlo hospital in Budapest, clearing the way for more clinical trials on the actual efficiency of the vaccine.

"The first trial was carried out on nine people," the CEO of Genetic Immunity's Hungarian arm, Zsolt Lisziewicz, told Deutsche Presse-Agentur (dpa). "The goal was to check the safety and toxicity of the vaccine. We didn't find any side effects."

The next step is to prove that the vaccine patch, named DermaVir, can work as well on humans as it did on monkeys during an earlier trial.

Human trials starting soon
Human trials in Sweden, the US and other European countries are set to begin in September, with results expected in 2008.

According to Lisziewicz, the vaccine operates by training the patient's immune system to suppress the HI-virus, as opposed to the traditional antiretroviral drugs' method of targeting the virus directly.

While the vaccine is not designed to prevent the spread of HIV/Aids or cure the disease completely, the researchers believe it could be used to prevent full-blown Aids ever developing.

"If we can keep the viral load down, the quality of life of HIV suffers will be increased," Lisziewicz said.

Hungarian scientist Julianna Lisziewicz has been leading the vaccine development in the US since 1996, and the monkey trials seemed to show great results.

"The very first trial we did was with late-Aids monkeys that were expected to live for only two weeks," Lisziewicz said. "They survived for over a year."

Virus may be suppressed
However, he said that the animal trials showed that if the disease was caught early enough, the immune system could be trained to almost completely suppress the virus.

"The goal was to suppress the viral load and in the best monkeys we did this to almost under the level of recognition," he said.

The clinical trial found that rhesus macaques infected with HIV who were treated with a combination of DermaVir and antiretroviral drugs saw their median viral load fall from 33 860 copies/ml to less than 200 copies/ml.

Average viral load of the monkeys with Aids that were treated with the same combination fell from over four million to less than 200. Monkeys that did not receive DermoVir showed no drop in viral load.

Patch could simplify treatment
The delivery system through a patch is also something that the company feels could be of major benefit due to its simple nature.

"With the patch you don't need to use needles, which can be dangerous garbage after use," Lisziewicz said. "In Africa and Asia it is difficult to control re-use of needles because the infrastructure is not so developed."

The researchers believe that, based on their preliminary data, the treatment would consist of applying the patch to a patient's back for a two-hour period six times a year.

Despite the fact that the trials on the monkeys also used antiretroviral drugs, the researchers hope the patch could also eliminate the need to take a daily concoction of pills.

An end to ARVs?
"Our realistic objective today is to treat people with HIV without (antiretroviral) drugs," said Lisziewicz. "If we give them DermaVir, they will probably never need drug treatment."

Antiretrovirals, which slow down the spread of the HI-virus, need to be taken in combination and this can mean taking many different types of pills throughout the day.

However, there is still a long way to go before anyone can get too excited, and outside observers remain guarded.

Still early days
A spokesman for The World Health Organization's HIV/Aids department declined to comment, saying that the research was in too early a phase, with little information on efficacy and/or the safety of the trials.

However, he said that immune-based therapy could be a promising therapeutic area in the future for HIV and many other infectious diseases.

Nonetheless, Genetic Immunity believes it is on the right track, and hopes to have some kind of limited production in Hungary by 2009. "Phase 2 clinical trials are expected to finish next year. If we get a good toxicity profile and acceptable efficacy, we hope to receive limited marketing approval," Lisziewicz said.

"We then do Phase 3 and we hope to have the patch ready not much later than 2009, although this is the most optimistic and assumes the next two trials will go well," he continued. – (Sapa-dpa)