What the HPTN 052 Study Means for Gay Men
By STEPHEN FALLON, PHD
Big news lit up the Internet this week: HIV treatments seem to block the virus from spreading during sex. Researchers from the National Institutes of Health tracked more than 1,700 couples and found that “earlier initiation of (the medicines that fight HIV) led to a 96 percent reduction in HIV transmission to the HIV-uninfected partner.”
How does this work? Anti-HIV medicines interrupt the virus’ ability to multiply inside a person. Scientists suspected that if there’s less HIV in a person it’s less likely that any will leak out in their sexual fluids.
Up until now, most prior studies have traced backwards from outcomes. Researchers couldn’t be sure if some other cause might have lowered contagion. This time, they enrolled people first then watched what happened when they took medicines. That makes this study more convincing.
• Isn’t this great news in the battle against AIDS?
Don’t flush the condoms yet. It turns out, 97% of the couples studied were heterosexual, and half were women. While the protection afforded during straight vaginal sex probably applies to gay anal sex, too, this wasn’t specifically proven.
More importantly, nearly all of the patients studied were living outside the United States. Researchers had “difficulties enrolling (U.S.) participants into the study.” It’s possible that patients in the other countries (Botswana, Brazil, India, Kenya, Malawi, South Africa, Thailand, and Zimbabwe) were more diligent about taking their medicines than typical Western patients are, because the consequences of HIV are starkly more visible in their homelands.
Unfortunately, HIV is not a forgiving disease; if patients skip more than a few doses the virus roars back. In the U.S. and Europe, patients who start out faithfully taking HIV medications typically backslide after two years on treatment, dropping to take less than three-out-of-four doses on time.
If people skip doses, their virus levels won’t drop enough, and any prevention benefits will disappear. Worse, if they spread HIV now, it will probably be a more deadly, drug resistant virus. A 2002 study found that among people unable to fully control their virus, every tenfold increase in HIV levels made them 81 percent more likely to pass HIV to a partner.
• Whether or not HIV medications stop new infections for U.S. gay men, shouldn’t everyone who’s HIV+ take medicines right away, to protect their own health?
Here, things get much murkier. The question about when to start treatment has been debated for years. Delivered at the right time, anti-HIV medications add years, or even decades to life expectancy. But they also often trigger troublesome side effects such as diarrhea, nausea, fatigue, sleep problems, sexual dysfunction, and even hair loss. Over time, their effects on the body’s balances can lead to heart attacks and strokes, liver failure, anemia, diabetes, chronic depression, kidney failure, embarrassing changes in body shape, and more. So the rationale has been to spare people these effects, and only start prescribing medicines when they’re truly needed to support life.
The new NIH study may lead physicians to prescribe HIV treatment even earlier than the nation’s guidelines currently recommend. But it’s not yet entirely clear that the earliest possible treatment lengthens life. It might just add more years of side effects without any net benefit.
Even this week’s study did not find a definite life benefit for those under early treatment. The authors noted, “There were also 23 deaths during the study. Ten occurred in the immediate treatment group and 13 in the deferred treatment group, a difference that did not reach statistical significance.”
• “It’s time for you to take my pills for me.”
The new study raises an ethical question: who is treatment for? If HIV treatment can truly stop the virus from spreading, then shouldn’t it be “forced” on people living with HIV, whether it adds years to their lives or not? Is treatment supposed to benefit the person living with HIV, or protect the person who might have sex with you?
Unfortunately, very early treatment for the sake of prevention might cause people to “burn through” the best medicines early in their infection, leaving nothing to fall back on when their immune prognosis becomes dire. This would consign those living with HIV to additional years living with complications, and possibly a shorter life expectancy, all in the name of protecting others.
Public health officials do impose treatment for medical conditions such as multi-drug resistant tuberculosis, which can is passed to others through casual contact. But HIV is not that sort of disease. It transmits only through specific, intimate contacts (unprotected sex, sharing needles, nursing babies, rare hospital mistakes). So uninfected people can consciously protect themselves from HIV.
In fact, the most important step to prevent the spread of HIV is simply getting people tested. The vast majority of diagnosed people take steps to protect their partners. Diagnosed people living with HIV have just a one-to-two percent chance of passing their virus each year, and that number is driven up by a few bad players; many never infect anyone else. Even in the NIH study, only 27 partners of the nearly 500 persons not taking treatment became infected over six years.
What if the gay community comes to believe that treatment provides the best firewall against infection? Will guys be less likely to use condoms? Is the pill bottle a more effective condom?
Pills can’t help when nearly ten percent of all people newly infected had caught HIV from someone else who was himself also just infected. During this early phase, the tests often can’t detect HIV.
Here’s a scarier reason not to count on someone else’s medicines to protect you: it’s easier to verify that a guy is wearing a condom right now than to prove he has taken his medicines all week. What if a horny guy just tells you that he’s on treatment?
Medications should be dispensed primarily to benefit people living with a disease, not packaged in a rationale to defend the rest of us from their illness.
Of course, there will always be slip-ups: popped condoms and missed doses. That’s why neither condoms nor medicines alone will prevent every infection. We need treatment and prevention, not treatment as prevention.
SOURCES:
HIV Prevention Trials Network Report 96% reduction in HIV transmission with treatment: National Institutes of Health, National Institute of Allergy and Infectious Diseases. “Treating HIV-infected People with Antiretrovirals Protects Partners from Infection: Findings Result from NIH-funded International Study.” May 11, 2011. http://www.niaid.nih.gov/news/newsreleases/2011/Pages/HPTN052.aspx
Newly infected heterosexual with high viral load 12x more likely to infect their wives: Wawer M. “Rates of HIV-1 Transmission per Coital Act, by Stage of HIV-1 Infection, in Rakai, Uganda. The Journal of Infectious Diseases.” Journal of Infectious Diseases, May 1, 2005;191:1391-1393,1403-1409.
HIV levels in semen typically 20x higher during first two months of infection: Pilcher C.,
et al. “Estimating transmission probabilities over time in acute HIV infection from biological data,” 9th Conference on Retroviruses and Opportunistic Infections, Feb. 24-28, 2002; Poster 366-M.
Low adherence rates with other chronic diseases:
Glaucoma Kass et al. (asymptomatic) AJO, 101:515, 1986.
Epilepsy, Cramer et al. (asymptomatic, until episodes) JAMA 261:3273; 1989.
Ankylosing Spondylitis (pain causing condition) de Klerk & van der Linden.
HIV treatment adherence declines by two years: Lima V, Harrigan R, Bangsberg D. “The Combined Effect of Modern Highly Active Antiretroviral Therapy Regimens and Adherence on Mortality over Time.” Journal of AIDS 2009, Vol. 50; No. 5: P. 529-536.
Old belief that medicines could push HIV out of a person forever: Ho D. “Toward HIV Eradication or Remission: The Tasks Ahead.“ Science 19 June 1998:
Vol. 280 no. 5371 pp. 1866-1867
Ho D. “Can HIV Be Eradicated?” 4th Conference on Retroviruses and Opportunistic Infections, January 22-26, 1997, Washington, DC.
Directly observed TB therapy: Salomon J, et al. “Cost-Effectiveness of Treating Multidrug-Resistant Tuberculosis,” Public Library of Science Medicine 2006;3(7):e241.
Acutely infected account for spread of 9% of all new infections: Pinkerton S. How many
sexually-acquired HIV infections in the USA are due to acute-phase HIV transmission? AIDS. 2007; 21(12): 1625–1629.
Risk of a PLWH passing virus is 1% – 2% per year: Holtgrave DR, Anderson T. Utilizing HIV transmission rates to assist in prioritizing HIV prevention services. Inernational Journal of STDs and AIDS. 2004;15:789-792.
Holtgrave D. “Estimation of Annual HIV Transmission Rates in the United States, 1978-2000,” Journal of Acquired Immune Deficiency Syndromes 2004;35(1):89-92.
First true link demonstrates decreasing VL = decreasing odds of transmission for HIV 1-E: Tovanabutra S, et al. “Male Viral Load and Heterosexual Transmission of HIV-1 Subtype E in Northern Thailand. Journal of Acquired Immune Deficiency Syndromes. 29(3):275-283, March 1, 2002.
Patients can burn through all available medicines in a few years: Sabine C, et al. “Treatment Exhaustion of Highly Active Antiretroviral Therapy (HAART) Among Individuals Infected with
HIV in the United Kingdom: Multicentre Cohort Study,” British Medical Journal March 2005;330:695.