Zimbabwe to conduct first HIV vaccine trial

Zimbabwe is preparing to conduct its first ever HIV vaccine trial as part of efforts to curb the spread of HIV.

Zimbabwe is one of countries hardest hit by HIV/AIDS, with an estimated adult HIV prevalence of 15 percent and 1.4 million people living with HIV out of a population of 14 million people.

About 800,000 HIV-positive people in the country are also on anti-retroviral drugs.

Lynda Stranix-Chibanda, a paediatrician at the University of Zimbabwe College of Health Sciences is leading the initiative on behalf of the HIV Vaccine Trials Network (HVTN) in conjunction with the University of Zimbabwe and University of California San Francisco (UZ-UCSF) Collaborative Research Program.

Stranix-Chibanda told Xinhua in a recent interview that trials for the preventive vaccine may start in October this year if the study protocol currently undergoing revision is approved by regulatory authorities.

"The earliest we could start is October but I will be happy if we start this year. You don't rush things," Stranix-Chibanda said.

The clinical trials, targeting HIV-negative adults, will be conducted at Seke South Clinic in Harare's dormitory town of Chitungwiza.

Twenty-six people will be involved in HVTN107, the first in a series of early phase clinical trials and about 50 in HVTN113, the second trial scheduled for Zimbabwe in2016, she said.

"The study participants will be with us for an intense three years. We will measure the response of their immune system to the vaccine and what happens to that response over time because if it only lasts for one year, it's not good enough - we will have to go back to the laboratory," she said.

The UZ paediatrician said vaccines were the most effective public health intervention to control infectious diseases in the long-term.

While global efforts were ongoing to develop a safe and effective HIV vaccine, it would take at least 10 years before a vaccine was licensed for use, she said.

In the meantime, prevention strategies such as abstinence, faithfulness, condoms, male circumcision and treatment of sexually transmitted infections needed to be enhanced.

"Those have to be enhanced but they are short-term strategies. What we need to do now is to push all prevention efforts, push treatment efforts, while we push for the science to catch up and give us a vaccine that works," Stranix-Chibanda said.

She said the same trials will be conducted in Zambia, South Africa and Malawi as part of regional efforts to combat the pandemic.

The HVTN107 vaccine to be tested Zimbabwe and other southern African countries is based on one used in Thailand's RV144 trial which was partially successful at preventing new HIV infections among vaccinated adults.

The RV144 trial completed in 2009 showed a modest 31 percent reduction in HIV risk three and a half years after the vaccines were given.

Further analysis showed that the vaccines offered a 60 percent reduction in risk a year after they were given.

Stranix-Chibanda said the RV144 was not being replicated in its original form but had been modified for the HIV strain found in southern Africa.

"The engineers have designed a product specifically for the virus that circulates in Sub-Saharan Africa," said the scientist who is also involved in Zimbabwe's prevention of mother to child transmission research programme.

"The RV144 in Thailand was designed for the HIV strain in Asia but we have a different HIV strain in Sub-Saharan Africa.

"So the engineers took the results from the Thailand trial and they have modified the vaccine to design it for the Sub Type C that we have in Africa," she added.

The scientist also dispelled myths about the HIV vaccine, saying human beings will not be used as guinea pigs as pre-clinical trials had long been done.

The vaccine trails would also not spread HIV because the study vaccines do not contain real HIV but are genetically constructed in the laboratory.

"We are not injecting the actual HIV virus into somebody like we do for measles. It's a different type of vaccine and it's something that is engineered in the laboratories," she explained.

As the scientists prepare for the trials, Stranix-Chibanda said they had started conducting awareness campaigns in communities to ensure people understood their rights and processes involved in research and vaccine trials.

She said other countries in southern Africa have also joined the initiative as the sub-region promotes efforts to curb spread of the disease, with South Africa already conducting the HVTN100 trial which it started in February this year. Endit