Could a new vaccine spell the end of HIV/Aids?

Bada Pharasi

Bada Pharasi

Published Dec 2, 2023


South Africa has made great strides in fighting the HIV epidemic. HIV prevalence showed a decline in people living with HIV in South Africa. Statistics showed a decline with figures standing at 14% in 2017 to 12.7% in 2022, based on findings from the Human Sciences Research Council (HSRC). Although the country is progressing, there’s still much to do to reach the UNAIDS 95-95-95 target. Innovations in HIV therapy have improved quite significantly, however as we all know current treatment efforts available for the South African public are to manage the virus. Experts maintain that producing a vaccine would make a drastic impact.

The CEO of the Innovative Pharmaceutical Association of South Africa, Bada Pharasi, writes that having already claimed the lives of over 40 million people globally, at the end of 2022, reports suggest that 39 million people were still living with HIV/Aids, with South Africa having the largest percentage worldwide.

While there is currently no cure, there is hope in the form of a possible vaccination. The majority of people living with HIV rely on antiretroviral treatment and become non-infectious over time. Therefore, increasing treatment coverage is critical not only to the individuals with HIV, but also in limiting the spread to others. With the current treatment coverage level sitting at 73.2%, it is critical that all measures are taken to get this closer to 100%.

Newer HIV medicines and short treatments for opportunistic infections like cryptococcal meningitis are being developed, and preventative medicines such as pre-exposure prophylaxis (PreP) are already available, with access to injectable formulations on the cards1. This begs the question - could a vaccine prevent HIV/Aids?

The US National Institutes of Health (NIH) is researching vaccines that can prevent HIV infection, and its potential for controlling and eradicating the HIV/AIDS pandemic makes it a priority. Even a partially effective vaccine could decrease the number of people who get HIV, thereby further reducing the number of people who can spread the virus to others. A trial of preventive HIV vaccine candidates has already begun in the US and South Africa. The phase 1 trial will evaluate a novel vaccine known as VIR-1388, for its safety and ability to induce an HIV-specific immune response in people.

The vaccine is designed to instruct the immune system to produce T cells that can recognise HIV and signal an immune response to prevent the virus from establishing chronic infection. It uses a cytomegalovirus (CMV) vector, meaning that a weakened version of CMV delivers the HIV vaccine to the immune system without causing disease in the study participants.

CMV has actually been present in much of the global population for centuries, with the majority of people living with it experiencing no symptoms. CMV remains detectable in the body for life, which suggests it has the potential to deliver and then safely help the body retain the HIV vaccine material for a long period, potentially overcoming the waning immunity observed with more short-lived vaccine vectors.

The HVTN-142 study is currently assessing the safety, reactogenicity and immunogenicity of VIR-13884, and is taking place across six sites in the US and four in South Africa, and will enrol 95 HIV-negative participants. Initial results are expected in late 2024, and an optional long-term sub-study will follow volunteers for up to three years after their first vaccine dose3. These trials, if successful, could see the end of the HIV virus. There is, however, no indication yet of how affordable these vaccines will be, especially to vulnerable communities.

Also in question regarding cost is a preventative injection for HIV called CAB-LA, which essentially eliminates a person’s chances of contracting HIV through sex, if taken every eight weeks. The injection contains an antiretroviral drug, Cabotegravir, which is released in the body over a two-month period.

While this solution is promising, the cost is simply too high. South Africa’s Department of Health notes that the non-profit price of between R540 and R570 per shot of the anti-HIV injection from UK-based manufacturer, ViiV Healthcare, is more than four times what the government can afford to pay.

The good news is that in March this year, ViiV Healthcare awarded licences to three Indian pharmaceutical manufacturers to produce cheaper, generic versions of CAB-LA. Fortunately, one of these manufacturers has a plant in Durban, where it is planning to manufacture the jab. However, the company first needs the technology and logistics to do so.

These generics will likely become available in 2027. Until then, the branded drug's price needs to be as low as possible. For CAB-LA to be cost-effective, it would need to be available at around R129 for a two-month supply.

In a positive development, the Pretoria High Court has given the go-ahead to the Pharmacist-Initiated Management of Antiretroviral Therapy, a necessary intervention to combat South Africa’s alarming HIV statistics.

The move will see pharmacies being allowed to administer HIV drugs directly to patients and is a decision hailed by the South African Pharmacy Council as a move in the right direction.

By working together to develop innovative responses to the disease, interventions such as these will significantly expand access to life-saving treatments, alleviate the strain on the already overburdened health-care system, provide care to areas that need it most, ensure that no community is left out, and hopefully, save the lives of millions living with the disease.

Bada Pharasi,CEO of the Innovative Pharmaceutical Association of South Africa (IPASA).

Saturday Star