The Kenya AIDS Vaccine Initiative–Ins***ute of Clinical Research at the University of Nairobi is among agencies collaborating in the International AIDS Vaccine Initiative (IAVI)’s Phase I clinical trial (IAVI W001) to test a novel HIV vaccine candidate, BG505 SOSIP.664 gp140.
The aim of the trial is to *****s the safety of the candidate and to determine if vaccination induces the human immune system to produce proteins known as neutralising antibo**** (NAbs).
Other collaborators in the trial include the Fred Hutchinson ****** Research Center, Seattle HIV Vaccine Trials Unit; M***achusetts General **spital, Translational and Clinical Research Center (Boston); and the pharmaceutical company GSK. Julie McElrath, M.D., Ph.D., senior vice president and director of the Vaccine and Infectious ******* Division, is the principal investigator at Fred Hutchinson ****** Research Center. Dr McElrath said: “We **pe that presenting this t***er to the human immune system w*** give us a unique view into a process that we want to harness to design an effective HIV vaccine.”
Professor Omu Anzala, MBChB, Ph.D., of the University of Nairobi and the Kenya AIDS Vaccine Initiative, and principal investigator at the KAVI-ICR site, said: “Every HIV vaccine trial generates new information that brings the international community closer to the discovery of a safe, effective HIV vaccine. We and our partners are excited about the new candidate and this new approach as we begin this trial.”
Mark Feinberg, M.D., Ph.D., president and CEO of IAVI, said: “This trial is unique because it represents the fruition of decades of scientific research to engineer this promising vaccine candidate. Much important work was done in the late 1990s and early 2000s to attempt to ****ilize the HIV envelope protein in its native configuration, but this difficult work took several more years to achieve.”
BG505 SOSIP.664 gp140 is based on the HIV envelope protein (Env), which is sha*** like a three-pronged ****e. This configuration, known as a t***er, is a target for antibo**** produced by the human immune system after infection. Some of these antibo**** are able to block viral entry into cells.
The BG505 SOSIP.664 gp140 t***er was engineered by a team directed by John P. Moore, Ph.D., at the We*** Cornell Medical College; Rogier Sanders, Ph.D., now at the University of Amsterdam Academic Medical Center; and Andrew B. ***d, Ph.D., and Ian A. Wilson, D.Phil., at Scripps Research. The outcome of their work was an important advance in ****ilizing the highly fragile Env protein in a native-like configuration.
This is one of the first clinical trials of a native-like Env t***er, and the first time that this particular t***er is being evaluated in humans. Previous vaccine trials involving Env concepts have tested the immunogenicity of only a portion of the Env structure or proteins that do not resemble the native structure. In **************, vaccination with BG505 SOSIP.664 gp140 caused B cells to produce antibo**** that neutralised the virus type from which the engineered immunogen was derived. Investigators **pe to see a similar specific response in humans.
Many vaccine researchers agree that a goal of HIV vaccination w*** be to produce a particular type of NAb known as a broadly neutralising antibody (bNAb). These antibo**** can neutralise a wide range of genetically variable HIV strains in laboratory tests, and stu**** s**w that some bNAbs can protect monkeys against a virus that is similar to HIV. This suggests that a vaccine that is able to induce similar antibo**** in people might protect them against HIV infection.
T**ugh it is not likely that vaccination with BG505 SOSIP.664 gp140 on its own w*** directly lead to the production of bNAbs, the **pe is that it could allow researchers to better understand what is required to induce bNAb responses. As Bruce D. Walker, M.D., trial collaborator at the W001 Boston trial site and director of the Ragon Ins***ute of M***achusetts General **spital, MIT, and Harvard, notes: “This is a critical trial that has broad implications for defining the path to generating broadly neutralising antibo**** that w*** be needed for a fully protective vaccine.” Data from the trial w*** likely contribute to the development of the vaccine candidate for future trials.
Dr Feinberg added: “We are gratif*** and invigorated by the cooperative spirit that binds the different ins***utions and researchers that have develo*** the candidate and are conducting the trial. This collaborative effort gives us great encouragement that the scientific community w*** succeed at developing an effective HIV vaccine.”
The IAVI W001 trial w*** enroll approximately 60 healthy ***** volunteers in Seattle, Boston, and Nairobi. Participants w*** receive three administrations of BG505 SOSIP.664 gp140 formulated with the AS01B1 adjuvant develo*** by GSK, or placebo. Adjuvants are substances used to enhance immune responses induced by a vaccine, and the AS01 adjuvant is used in licensed vaccines.
Read: Kenya leads Africa with Sh34 billion in startups deals in 2018
The vaccine candidate is administered through intramuscular injection. Teams at the trial locations w*** monitor participants to *****s the vaccine candidate’s safety and ability to elicit immune system responses.
Results of the IAVI W001 trial are expected in 2020.
4 Comments