AIDS vaccine trial offers new hope

By Cassandra Bernard

A recent vaccine trial gives hope to those living with HIV, says the executive director of AIDS PEI, Mark Hanlon.

The biggest vaccine trial ever was performed in Thailand and produced encouraging results. Volunteers who received the vaccine had a 31 per cent deduction in the rate of HIV compared to those who took the placebo, according to a recent study.

Hanlon said the only catch is the antibodies are never close enough to match HIV perfectly because forms of HIV around the world can differ and have different genetic structures.

“There was success in Thailand, but that doesn’t mean the vaccine will be successful elsewhere.

About 16,400 volunteers took part in the trial. Half were injected with the vaccine and only 51 were infected. When the other half took the placebo to fight HIV, 74 of them were infected.

The trial examined vaccine impact on risk of infection and on viral load among vaccine and placebo recipients who received the vaccine and went on to acquire HIV.

 The vaccine has two components; an immune system primer, Sanofi-Pasteur’s ALVAC Canary, a canaryprox virus engineered to contain HIV genes. The second component AIDS Vax mimics the genetic makeup of HIV. It makes the body react and produce antibodies to fight off the HIV.

The vaccine contained fragments of the subtype E strain common in Thailand and Southeast Asia, and fragments of subtype B strain common in Europe and North America. It is not known if it would be effective in strains found in other geographical regions. Follow up studies will be conducted later on to determine this.

Every other trial performed was ineffective and in some cases increased the risk of HIV, Hanlon said.

“The fact they got this far, at 31 per cent, it is hugely encouraging.”

Hanlon said trials have taken place in Canada but failed. Researchers and scientists thought they were usless, but are now hopeful that the vaccine could someday be used as a treatment.

“There is hope clients and people that live with HIV can be injected and not have to take a pill every day, it could be a new method of treatment.”

It’s difficult to know where researchers will be in 10 years from now, Hanlon said.

“Thirty-one per cent is a high number, but not as high as we would like, we need to be at at least 80 per cent.” 

Bachir Sarr with The Canadian Aids Society in Ottawa said the study started in 2003 and ever since then they send out all information and results to every AIDS organization in the country.

“The results of the trial in Thailand will be discussed in more detail in Paris at the end of October.”

The  main thing is they have to be cautious of what the results mean at this time, Sarr said.

“That is why we perform these trials, even though the results show improvement doesn’t mean it will ever be 100 per cent affective against HIV.”