A breakthrough HIV antibody candidate, researchers say, is more efficacious than natural resistance in rare individuals who are infected with the disease. Nearly 37 million people have died waiting for a cure since HIV first appeared.
The new antibody attacks 99 percent of known HIV strains and prevents infection in primates. The study, published in the medical journal Science on September 20, and in collaboration with the U.S. National Institutes of Health (NIH), suggests that three antibodies combined together prevents infection in macaques. Clinical human trials are expected to begin in 2018.
Scientists across the globe have been competitively racing away at the conquest to engineer bispecific and trispecific antibodies to be the first to achieve an antibody-based treatment or even an HIV vaccine. The prize to be won?
His or her name etched in history.
Recently scientists from Harvard Medical School, Massachusetts Institute of Technology and The Scripps Research Institute all contributed to the findings. Twenty-four macaques were given antibodies and were later injected with two strains of SHIV (ape HIV). None of the monkeys who were given one specific antibody combination developed an infection.
The winning recipe combines the structures of three antibodies called VRC01, PGDM1400 and 10E8v4. Each SHIV strain would be susceptible to one antibody, while resistant to the others. Monkeys that were given only one or the other antibody were infected, but the ones that received the trispecific antibody show no signs of infection. The antibodies target infected cells in multiple ways, and the technology could eventually be applied to treatments against other infections, cancer and autoimmune diseases.
Paris-based pharmaceutical company Sanofi was part of the collaborative course of study. "They are more potent and have greater breadth than any single naturally occurring antibody that's been discovered," Gary J. Nabel, M.D., Ph.D., Chief Scientific Officer at Sanofi, told BBC online. "We're getting 99% coverage, and getting coverage at very low concentrations of the antibody." The National Institute of Allergy and Infectious Diseases, (NIAID) Vaccine Research Center (VRC) is also involved in the study.
Incredibly, the antibody works better than the naturally-occurring antibodies it was engineered from. The best naturally-occurring antibodies are capable of targeting up to 90 percent of HIV strains. People who are born with two copies of the CCR5 delta32 gene, from each parent, are the only ones who are virtually immune to HIV.
HIV's unique ability to mutate lets it adapt to nearly any situation the body or doctors can throw at it. Because of this, a host of HIV variations exists within a single patient's body. “Evolutionary modeling studies indicate less than a century has passed since the most recent common ancestor of the HIV-1 pandemic strains and, in that time frame, an extraordinarily diverse viral population has developed,” wrote researchers. That's the reason it's taken so long to get anywhere with an HIV vaccine. This means that there's as many variation of HIV as there are strains of influenza across the globe during peak flu season.
But other HIV patients develop what they call super-antibodies. It's human nature to eventually conquer over plagues and develop resistances to the worst diseases mankind has known. But the study's trispecific antibody works better than even naturally-occurring super-antibodies, which gives an indication to how important the technology will be.
There is currently no vaccine for HIV.
PrEP is the closest thing we have to a preventative vaccine—a prophylactic. But obviously PrEP itself isn't going to end the HIV epidemic in America.
Meanwhile, in South Africa, where HIV dominates, another study is underway. The study called HVTN 702 is examining one of the only vaccine candidates that have shown any actual success—the RV144 vaccine regimen. There, 5,400 men and women will be enrolled into the study. They'll all receive five injections of the vaccine over the course of a year.
In Thailand, another trial examined an HIV antibody candidate effectively blocked HIV infection in a man for 10 months.
The Joint United Nations Programme on HIV/AIDS (UNAIDS) estimates that worldwide, 36.7 million people have died from AIDS, and 30 percent of those who are HIV positive don't know their status. And it America's responsibility to lead the fight against disease, which includes developing a vaccine that works.
Given these new developments, it's safe to say that a vaccine is just around the corner, and hope is on the way.