By Wallace Mawire
HARARE
Zimbabwean scientists, in collaboration with a global consortium of researchers, are preparing to conduct the country's first-ever HIV vaccine trial as part of the global effort to find a lasting solution to the spread of HIV.
"The vaccine to be tested in Zimbabwe is a preventive vaccine that will be administered to HIV-negative people," clinical trials coordinator Dr. Portia Hunidzarira told The Anadolu Agency.
"Those already taking anti-retroviral treatments (ARTs) are not eligible," she explained, referring to the drug used to suppress the virus among people who already have HIV.
Hunidzarira said the trials aimed to determine whether the vaccine could prevent HIV-negative people from contracting the virus.
The trials will also gauge the safety of new vaccine products and regimens, while measuring the immune response among trial subjects.
Dr. Lynda Stranix-Chibanda, a pediatrician at the University of Zimbabwe, 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.
The HVTN is a publicly-funded multi-disciplinary global consortium of scientists tasked with facilitating the development of HIV/AIDS vaccines.
Stranix-Chibanda said the trials would likely be conducted in June at the Seke South Clinic in the town of Chitungwiza, located nearly 30km south of capital Harare.
They are currently pursuing regulatory approval mechanisms with the relevant authorities in Zambia. These authorities include the Chitungwiza Ethics Committee, the Joint Research Ethics Committee, the Medical Research Council of Zimbabwe, the Research Council of Zimbabwe, the National Biotechnology Authority of Zimbabwe and the Medical Control Authority of Zimbabwe.
Stranix-Chibanda said the vaccine to be tested was based on one used in Thailand's RV144 trial, which was moderately successful at preventing new HIV infections among vaccinated adults.
She added that RV144 had been modified for a sub-strain of the virus called Clade CHIV, which is found in southern Africa.
She went on to note that the HVTN107 vaccine – which will be tested in Zimbabwe and other southern African countries – had seen the addition of another booster, including an adjuvant to test the response as compared to RV144.
RV144 had a six-month vaccination schedule, while HVTN107 will have a 12-month schedule.
The trials in Thailand, which were reportedly administered to 16,000 adults, were 60 percent effective at one year and 31 percent effective at three years.
"The next phase of the program will involve the selection of the best candidates, further research to assess the effectiveness of the drug, and – if successful – licensure for use," Stranix-Chibanda told AA.
According to Emilder Chihota, a community educator participating in the UZ-UCSF Collaborative Research Program, 26 people will take part in the first phase of the vaccine trials.
She said the trials were part of a global effort to find an effective means of preventing new infections.
Stranix-Chibanda said Zimbabwe had been selected to join the initiative because the country's research environment was conducive to intense clinical trials.
She noted that HVTN had 30 research sites on five continents and had carried out 50 clinical trials since 1999, testing various HIV vaccines for safety, immunogenicity and efficacy.
The HVTN is funded by the U.S. National Institute of Health, the South African Medical Research Council, and the Bill and Melinda Gates Foundation, among others.
-Alarming-
Stranix-Chibanda said she had been moved to take part in the project by the problems HIV had caused in Zimbabwe and the region.
"As a pediatrician, l have long worked in Zimbabwe with mothers and babies trying to stop the spread of HIV," she told AA.
"l have also joined the global effort to find a lasting solution to the spread of HIV by finding a vaccine," she added.
According to Dr. Nyaradzo Mgodi, co-principal investigator at the UZ-UCSF, the rate of new infections in Zimbabwe remains alarming.
"A vaccine will benefit the population. We do not have a vaccine for HIV like we do for polio or measles," she told AA.
She said that other preventive measures – such as condoms or abstinence – were not very effective, although they helped reduce the spread of the disease.
"Due to human nature and behavioral changes, other preventive measures cannot be fully relied on. But a vaccine would be a stop-gap measure against new HIV infections," Mgodi asserted.
Hunidzarira, the clinical trials coordinator, agreed.
"We continue to put ourselves – and others – at risk of HIV infection," she said.
She noted that, due to poor logistical support in sub-Saharan Africa, only eight condoms were available each year for each sexually active person.
According to Hunidzarira, three out of five HIV-positive people in sub-Saharan Africa lack access to ARTs.
"Seventy-one percent of HIV-positive adults in sub-Saharan Africa could transmit the virus to others," she said.
