In November 2022 the results of the AELIX-002 trial were published in Nature by collaborators from Aelix Therapeutics and Gilead Sciences. This is the trial that Dr Christian Brander, Co-founder and Chief Scientific Officer at Aelix Therapeutics, hinted at in our exclusive interview during the World Vaccine Congress in Barcelona 2022. Dr Brander is reportedly “excited” to have his team’s results recorded in a “prestigious journal” with a global reach.  

The trial in context 

The WHO reported that in 2021 38.4 million people were living with HIV. WHO’s strategy for 2022-2030 aims to “reduce HIV infections from 1.5 million in 2020 to 335,000 by 2030”. UNAIDS reports that 28.7 million people were accessing antiretroviral therapy in 2021.

The authors of the study note that therapeutic vaccines targeted to HIV-specific immunity have been “postulated to be a key component of any HIV cure strategy”. Despite the safety and immunogenicity of different candidates in trials, “no reduction in HIV-1 viral reservoirs, prevention of viral rebound, or suppressed viremia off ART have been reported” in trials such as this one.  

A “potential reason” for previous “suboptimal trials outcomes” might be “T-cell immunogen designs and the induction of virus-specific T-cell responses with ineffective or insufficient antiviral activity”. In order to overcome this issue, HTI (HIVACAT T-cell immunogen)-based vaccines were designed to “induce functional HIV-1-specific T-cell responses that were associated with better viral control”.  

The trial meets endpoints 

The trial was a “double-blind, randomised, placebo-controlled trial” with the primary objective of safety evaluation. The secondary objectives “included T-cell immunogenicity, the effect on viral rebound, and the safety of an antiretroviral treatment interruption” (ATI). The study “demonstrated that HTI vaccines were safe, well-tolerated, and able to induce strong, polyfunctional, and broad CD4 and CD8 T-cell responses focused on the HTI immunogen sequence”.  

“The AELIX-002 trial results support the idea that the induction of HIV-specific T-cells is a key factor in improving post-rebound viral suppression during an ATI, while validating the design of the HTI immunogen to induce functional T-cell responses to vulnerable sites of the virus”.  

The authors believe that their findings “strongly support” the further use of HTI vaccines in “simpler regimens, given alone, or in combination”. A second study is also being conducted in collaboration with Gilead, according to Dr Brander remarked that the “T-cell vaccine approach has the potential to play a critical role in strategies to cure HIV infection”.  

“AELIX is a leader in developing vaccine-based solutions for an HIV cure.”  

For more on HIV strategies at the World Vaccine and Immunotherapy Congress get your tickets now.