Canadian-developed HIV vaccine approved for human studies

After two decades of research, a group of Canadian scientists has won approval to start testing an experimental HIV vaccine on humans.

The vaccine, developed by researchers at the University of Western Ontario, has received a green light from the U.S. Food and Drug Administration for clinical human trials.

Beginning in January, the vaccine will be given to 40 healthy people with HIV to test its safety.

Dr. Chil-Yong Kang, professor of virology at the Schulich School of Medicine and Dentistry at the University of Western Ontario, called the FDA approval a “milestone.”

“We started the basic science research two decades ago,” Kang said. “The vaccine development, we started 10 years ago. This is incredible for us to get to this stage of development.”

Kang said the vaccine, called SAV001, is the first preventative HIV vaccine approved for clinical trials to use a killed whole HIV-1 virus to activate the immune response in humans.

The strategy has been used before to develop successful vaccines for influenza, polio, rabies and hepatitis A. Kang said these past successes for other viral diseases provide hope the Canadian-developed vaccine will work against HIV.

The human immunodeficiency virus used in the vaccine has been genetically altered to render it non-pathogenic, or unable to cause disease. Kang and his research team then further inactivated the virus using chemicals and radiation.

“In the past, people did not use this strategy (using a killed whole HIV virus) because people did not know how to make a safer virus and people did not know how to make large quantities of it,” Kang said. “Now we have solved those problems by the genetic engineering of the virus.”

According to the International AIDS Vaccine Initiative, there are 30 HIV vaccines currently being tested in phase 1 clinical trials around the world.

Many of these vaccines have largely focused on using one specific component of the human immunodeficiency virus to trigger an immune response. Other vaccines have used other viral vectors to create a vaccine. Right now, there is no effective HIV vaccine.

Dr. Jonathan Angel, president of the Canadian Association for HIV Research, whose research is funded by the Canadian Institutes of Health Research, said it is exciting that a Canadian scientist’s work has progressed from the basic research level to a vaccine approved for human clinical trials, meeting the rigorous criteria of the FDA.

But he also cautioned that developing an effective HIV vaccine remains a daunting task because HIV is a complex virus that scientists do not yet completely understand.

Should the SAV001 be proven safe, the vaccine will enter the second phase of clinical trials, in which it will be tested on 600 HIV-negative volunteers at high risk for HIV infection. Researchers will measure the volunteers’ immune response to the vaccine.

The third and final phase would enroll 6,000 HIV-negative volunteers at high risk for the disease. The participants, half of whom would be vaccinated and half un-vaccinated, would be tracked for three years to see how many in each group became infected with HIV.

Kang and his team received funding from Sumagen Canada, a company created in 2008 to support the development of the vaccine and a subsidiary of a Korean-based pharmaceutical venture company.