Scientists from the Jupiter, Florida campus of The Scripps Research Institute (TSRI) plan to use a new multi-million-dollar award to develop an HIV/AIDS alternative vaccine that has demonstrated potential in animal models.
“The Bill and Melinda Gates Foundation is supporting the preclinical development leading us to human trials in about two to three years,” Michael Farzan, TSRI professor and research leader, told Vaccine News Daily.
In September, TSRI scientists were awarded approximately $6 million from the foundation to support four years of research funding. This is the first Gates Foundation grant awarded to a Scripps Florida scientist.
Farzan and his colleagues’ breakthrough research received worldwide attention when announced this year in the journal Nature. When the drug candidate, called eCD4-lg, was tested in the laboratory and in animal models, the results were so universally effective that they suggested the compound’s potential to serve the role of an alternative HIV/AIDS vaccine, according to the journal.
The drug candidate offered complete protection of animal models against the virus for up to one year, Farzan said.
“Our compound eCD4-Ig is the broadest and most potent entry inhibitor described so far, effective against all strains tested,” Farzan, who is also vice chairman of the TSRI Department of Immunology and Microbial Science, said. “At the end of our research, we expect to have enough evidence to develop a firm foundation to fully evaluate its potential as an alternative vaccine.”
Subsequently, he told Vaccine News Daily, the human trials will be “of our protein inhibitor eCD4-Ig, by itself, and its ability to suppress the virus in infected individuals.”
At the same time, the Gates Foundation grant will “support our preclinical efforts to further optimize the AAV [adeno-associated virus] delivery mechanism for this protein, which is the basis for our vaccine alternative,” Farzan said.
AAV vectors can stably express HIV-1 broadly neutralizing antibodies, according to the TSRI research, and the long-term in vivo expression of such a broad and potent entry inhibitor could circumvent the need for a conventional vaccine for HIV-1.
“Depending on the results of the human trials of the protein, and of parallel human studies delivering conventional antibodies via AAV, we hope to have follow-up studies testing the full vaccine approach in later years,” though he said the exact timing is uncertain," Farzan said.