Human immunodeficiency virus vaccines: Advances, challenges and future perspectives

In the past 40 years, much effort has been made to develop a vaccine that can prevent human immunodeficiency virus (HIV) infection. But till today, this continues to be an unresolved challenge. The main obstacle in developing a vaccine is the ability of the virus to mutate at a swift rate, thereby evading the immune system. This has dramatically slowed the progress in the development of an HIV vaccine. Previous studies, like RV144, have demonstrated limited protection. Current trials, such as Imbokodo and Mosaico, have shown that the vaccines used were safe but did not demonstrate efficacy against the HIV-1 virus. With the advent of mRNA vaccines and broad neutralising antibodies, research has shown some progress in developing a promising candidate vaccine. Recently, the use of mosaic antigens and germline-targeting techniques has shed light on the development of a promising candidate vaccine. These techniques educate the immune system slowly. This review tracks the progress of HIV vaccine development to date and examines the most promising new strategies that could ultimately lead to the development of an efficacious vaccine.