The long and challenging research on preventive Human Immunodeficiency Virus (HIV) vaccine has inspired hope after a recent hype suggests a breakthrough strategy offering fresh tools for battling the devastating virus.
At an international AIDS conference in February last year, researchers from Scripps Research and IAVI, a non-profit vaccine research organization, announced promising blood-test results from the first phase one human trial of a new HIV vaccine strategy.
The results, which are still unpublished, grabbed the public’s attention in a way that could only be possible in the era of social media.
According to William Schief, an immunologist at Scripps and executive director of vaccine design at IAVI’s Neutralizing Antibody Centre, the reality is far more nuanced than the hype suggests.
Although the immune response his team detected is an important proof-of-concept finding, he says, the field is still years away from producing shots that make people less likely to be infected with HIV.
“Scientifically, it is a beautiful concept,” Esparza says. “Practically, it will not be easy to implement.”
Still, after decades of setbacks, the results are welcome news—with some intriguing connections to the COVID-19 vaccine effort that may help accelerate the HIV work.
The search for an HIV vaccine has seen a major disappointment and a modest success.
The disappointment was experienced in 2020 when the Uhambo/HVTN 072 vaccine trial was terminated due to lack of efficacy.
The modest success came a year later when on 26 January it was announced that the AMP study, the first-ever efficacy trial of a so-called broadly neutralising antibody (bNAb), VRC01, produced a modest reduction in HIV infections, but a 75 per cent reduction in the class of viruses most sensitive to it.
Dr Mark Feinberg, President and CEO of IAVI, the International AIDS Vaccine Initiative, found grounds for optimism in the field when he gave a plenary talk at the recent HIV Research for Prevention (HIVR4P) virtual conference two days after the AMP study results were announced.
The Uhambo vaccine was only the fifth ever to be tested in a large phase III efficacy trial, in a history that goes back to 2003.
Its failure was especially disappointing as it was based on what was hoped would be an improvement to the only HIV vaccine that has ever shown evidence of efficacy – the one used in the RV144 trial that finished in 2009.
The reduction in HIV infections in people given the vaccine in that trial was only 28 per cent; it was hoped the Uhambo vaccine would be more efficacious.
“Quite clearly, we are getting closer to the goal of an effective immune therapy against HIV,” he said. “Though we still don’t know how long our journey will take.”
In Kenya, the first clinical trial took place in 2001 and was led by IAVI, University of Oxford and KAVI-Institute of Clinical Research at the University of Nairobi.
So far, Kenya Aids Vaccine Initiative (KAVI)- UoN has conducted over 18 HIV Vaccine clinical trials and is currently testing three phase 1 HIV Vaccine trials driving the search for an efficacious HIV Vaccine forward.
