If you listen too closely to mainstream media, it seems like a different cure for HIV is found every fortnight. In reality, many vaccines and treatments enter clinical trials but rarely succeed across a large population on a significant level. In fact since 1987 over 30 potential vaccines have been clinically tested among over ten thousand volunteers, but no preventative vaccine has been found.
An HIV vaccine is difficult to develop because it has a high degree of genetic divergence, a long latency period, and does not retain its antigenicity — i.e., does not cause the creation of antigens when it is killed. Obviously using a live viral vaccine is out of the question, and besides there are no fully recovered AIDS patients — only those who have decreased their viral count to undetectable levels and suppressed their symptoms through expensive retroviral drugs.
I mean, honestly, Time magazine’s just gone and published an article called “Death of AIDS in sight: a trial of the only vaccine to offer partial protection from HIV, after 30 years of research was started in South Africa this week.” The vaccine cost $125-million to develop, and will be tested by 100 HIV-negative participants. Results are expected to be published in 2019, but scientists are not overly optimistic.
I’d hardly call six years until a cure “in sight.” Maybe after thirty years toiling in a lab. But those scientists know better than anyone to not be overly optimistic. But the reporter? Nope. The “Death of AIDS” is merely sensationalist journalism. That implies a treatment that completely kills the virus inside an HIV positive individual.
Here’s a short timeline on AIDS and some of the more successful preventative treatments for the disease.
1981
HIV is discovered.
1984
The United States Health and Human Services Secretary declares that a vaccine will be available in two years.
1986
Nope.
2002
AIDS becomes the primary cause of death caused by an infectious agent in Africa.
2004
A 3000 participant worldwide clinical trial is conducted for V520, which uses a weakened adenovirus carrying three HIV gene segments to prompt the body to produce a cellular immune response to kill HIV-infected cells in about half of the volunteers. However the trial for V520 was discontinued after the vaccine appeared to increase HIV infection in some volunteers.
2009
RV144 is tested in Thailand, where it initially reduced infection rates by around 50% compared to the control group. However a year later its effectiveness in reducing infections fell to 26%. The Thai government deemed it too ineffective for production.
2011
Researchers in Madrid publish results from a clinical trial of the vaccine MVA-B, which reduces the lethality of AIDS to a milder, herpes-like infection 90% of the time. However the vaccine does not outright prevent HIV infection.
2012
Truvada is approved by the FDA for use by HIV-positive patients in preventing infection of their sexual partners. It is 99% effective when used in combination with retrovirals.
At the University of Western Ontario, a preventative vaccine based on a whole killed virus starts human trials – but only on HIV positive volunteers, to affirm that it is safe enough to test its efficacy on HIV negative volunteers.
I would be thrilled if an effective preventative HIV vaccine was developed. But let’s not get our hopes up over a bunch of clinical trials.
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