Truvada (emtricitabine and tenofovir disoproxil fumarate), manufactured by Gilead Sciences, is the first drug approved to reduce the risk of HIV infection. In a pre-exposure prophylaxis, or PrEP, regimen, HIV-negative people who are at high risk may take a daily dose of Truvada, which has been proven to lower their infection risk if they are exposed to the virus.

PrEP treatment is meant to be employed alongside other prevention methods, such as safer sex practices, risk-reduction counseling, and regular HIV testing.

In giving the green light to Truvada on July 16, 2012, FDA Commissioner Dr. Margaret A. Hamburg said, "Every year, about 50,000 U.S. adults and adolescents are diagnosed with HIV infection, despite the availability of prevention methods and strategies to educate, test, and care for people living with the disease. New treatments as well as prevention methods are needed to fight the HIV epidemic in this country."

See the Infographic: Truvada PrEP for Men Who Sleep with Men »

A Work in Progress

Dr. Kenneth Mayer, a visiting professor at Harvard Medical School and the medical research director at Boston’s Fenway Institute (a research center dedicated to providing medical services to LGBT communities), expressed a favorable opinion about Truvada for HIV prevention—while emphasizing that the drug’s use for this purpose is in its infancy.

“It has potential to help people,” he told Healthline. “Several randomized control trials show that it decreases HIV incidence, but it’s not a simple matter. It’s in its early days, and it’s very analogous to the early days of hormonal contraception. The initial hormonal contraception was only progestin. It was a very high dose, and that had more side effects … people got smarter about how to give it less frequently and to modulate the chemicals.”

In trials, Truvada has proved, overall, to be safe and well tolerated, though a small minority of people did show some side effects. And many medical experts and HIV experts have raised serious concerns about the ability of high-risk patients to consistently take a pill every day—if it’s not taken daily, it loses efficacy, and there are fears that poor adherence to a daily schedule could lead to HIV infections and Truvada-resistant strains of HIV.

Dr. Mayer said that it is important for healthcare providers to determine patients’ motivations and their willingness to be monitored: “It’s not a vaccine," he explained. "It’s a commitment to taking pills on a regular basis."

Thomas D. Chiampas, Pharm.D., BCPS, AAHIVP, a clinical assistant professor and clinical pharmacist at the University of Illinois College of Pharmacy, was initially skeptical about the use of Truvada for PrEP. But after reading the results of studies and talking to preceptors and students, he echoed Dr. Mayer’s sentiments.

“I do think Truvada for PrEP, when safe for the patient and taken appropriately with 100 percent medication adherence, does have the potential to diminish HIV transmission and thus AIDS infections. At our clinics we only see HIV-positive individuals; therefore, we do not prescribe Truvada for PrEP," he said. "I do believe more education is needed about Truvada for PrEP—in particular, appropriate prescribing duration, assessment of risk factors, assessment of adherence, and lab monitoring,” he said.

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A Numbers Game

According to several accounts, 1,774 people filled prescriptions for Truvada for PrEP between January 2011 and March 2013. But while those numbers may seem low, many others are receiving the medication through ongoing clinical trials.

And at about $13,000 a year, Truvada for PrEP does not come cheap. While most insurance companies in the U.S. cover Truvada, affordability can be an issue if a person has a high-copay insurance plan. “For many people, it’s not necessarily expensive, but it does involve people being motivated consumers, since a physician might have to get prior approval with some insurance companies,” said Dr. Mayer.

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Education Is Key

There is some agreement among the medical community that riskier sexual behavior is on the rise, and that more education about HIV and AIDS prevention is crucial.

Fenway Health is one of several groups that have received non-restricted educational and research grants from Gilead Sciences, according to Dr. Mayer. “We’ve used some of the funding to convene a conference about best practices in HIV prevention and have developed some educational materials for people in the community, so they can be informed consumers. Their goal is not to push people to use PrEP, but [to let them] know about it. Obviously, it’s not the answer for some people,” he said.

Fenway has also conducted research on whether people are starting to use the medication, what people know about it, and what concerns they have.

One eye-opening finding of the focus group is that some people are not comfortable talking about their sexual behavior with their doctors, according to Dr. Mayer.

“This medication is not something that you would give to everybody,” said Dr. Mayer. “It is individuals who are having unprotected sexual behavior with any regularity, particularly if they have a known HIV-infected partner, who are the key targets for using PrEP. There are a number of people who said, ‘Well, I wouldn’t be comfortable divulging my behavior to my doctor, so I don’t know how I would ask for it.’ That was one concern.”

“The focus group findings also revealed that even though the drugs’ side effect profile is quite low, some individuals felt that any risk of any side effect was unacceptable if they were otherwise healthy,” he added.

What Are the Side Effects?

Acknowledging that tenofovir has been associated with kidney problems in HIV-infected people, Dr. Mayer believes that this side effect is not a major drawback if patients are monitored.

“The kidney problems that people are monitored for tend to be self-limited. You stop the medication, and the creatinine [which is evidence of kidney dysfunction] goes back to normal, so it’s not as if people automatically go into irreversible kidney failure," Dr. Mayer explained. "But what it means is, particularly if they have preexisting kidney disease, or, for example, untreated hypertension for a long time, if they go on the medication, they need to be carefully monitored. We do kidney function within a month after people start the medication, and then if it looks good, we do quarterly monitoring of kidney function. So that’s an important side effect. It’s uncommon though; it was in the 1 percent to 2 percent range that people had to stop the medication because of kidney problems in the course of the trials.”

Other side effects reported in trials include weight loss (2 percent), nausea (2 percent), and headache (4 percent), according to Fenway Medical.

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Complacent Attitudes and Risky Behaviors?

Many medical professionals agree that the current generation of sexually active young adults is more complacent about HIV and AIDS than the generation before it.

For much of the 1980s and early 1990s, the lack of effective treatments for AIDS made the disease more frightening. But current therapies are so effective that HIV/AIDS is widely seen as a manageable health condition, not the death sentence it once was. And this may lead to young people being lax when it comes to safe sex practices.

Dr. Mayer explains, “Young people may feel invulnerable and the epidemic may be quieter for them, because they don’t know people with AIDS. Years ago, the drugs had more side effects and people were sicker. In many cities, you could spot people that you had the sense might have AIDS … and that’s not the case anymore.”

As such, one major concern for medical professionals is whether using Truvada will lead to riskier sexual practices—and thereby increase people’s risk for other STDs.

Maurizio Bonacini, M.D., is an associate clinical professor at the University of California, San Francisco, and the director of the HIV-Liver program at California Pacific Medical Center. He is adamantly opposed to Truvada for AIDS prevention: “I found it appalling that Truvada was approved to prevent HIV. So now we will have people that have high risk sex taking a tablet with questionable adherence, and placing themselves at risk for HBV [hepatitis B], HCV [hepatitis C], HAV [hepatitis A], HSV [herpes simplex virus], HPV [human papillomavirus], and whatever other acronym that will spell health trouble,” he said

Fred Mayer, R.Ph., the president of Pharmacists Planning Service Inc. (PPSI), a California non-profit corporation that offers a large number of health-awareness programs to promote public health and education, gave a thumbs-up to Truvada for prevention, but feels that there is not enough of a promotional push for using the drug in conjunction with condoms and other safer sex practices.

“I think any new development in prescription drugs, especially for AIDS, is great as a consumer advocate," Mayer said. "The only downside I see as a consumer advocate with a public health pharmacy organization is they are promoting this drug as an AIDS preventative and should be promoting this drug with the use of condoms, for prevention of STDs, STIs, chlamydia, et cetera,” he said.

Chiampas agrees: “People think, ‘OK, it’s a pill I can take.’ But adherence counseling, follow-up for labs and assessments, pregnancy tests, hepatitis tests, sexually transmitted diseases, HIV—all of those tests need to be drawn every two to three months to six months out for safety concerns.”

See the Infographic: Truvada PrEP for Men Who Sleep with Men »

New Avenues for Education and Counseling

In terms of public health initiatives, social media presents new opportunities and new challenges. In the recent past, materials for people who are at high risk for AIDS were provided at places where they congregated. “For example, [if] gay men meet in a bar or club, you can do lot of education, you can have materials in the club—people would know where to go to recruit people for trials and studies,” said Dr. Mayer.

But as more and more people are socializing and finding sexual partners on their handheld devices, outreach can be more difficult.

“We’ve learned to be creative,” said Dr. Mayer. “The challenge is that organizations that in the past helped instill a sense of community… are not as strong anymore, because people are meeting partners online. On the other hand, with the Internet you can also offer a lot of education materials and you can educate people in the privacy of their home. It’s a matter of figuring out creative ways.”

Josh Robbins, an HIV activist and patient advocate and blogger, has recently launched a digital LGBT PrEP Guide for HIV Prevention at I'm Still Josh. “I fall short of endorsing PrEP because I don’t believe that’s the best place for our voice,” said Robbins. "What I believe in is giving people the power to be informed and then to make an educated decision with their physician or healthcare provider."

Robbins explained, "I’m not saying PrEP is right for everybody, but I’m not saying you should ignore PrEP. It is important, maybe, for me to say that, because the FDA has neither tested nor approved a condom for anal sex. PrEP is the only FDA-approved prevention method. It is the only one in the arsenal when we talk about what do we have for the prevention of HIV… as long as you have an educated discussion with a physician or whoever is the stakeholder in helping you make a decision, then, whether I agree with your decision or not, at the end of the day I’m glad that you had that discussion.”

Chiampas and one of his colleagues are planning to conduct a survey for general practitioners to see how comfortable they feel about Truvada. “Our concerns are the appropriate monitoring and follow-up, as well as counseling," he said.

He added that people on a PrEP regimen should be seen by a healthcare provider every two to three months, to be tested for HIV, kidney function, pregnancy, and other things. “The adherence issue cannot be stressed enough,” he said. “But when taken with 100 percent adherence, Truvada for PrEP was very effective in preventing HIV transmission between homosexual, heterosexual, and injection drug-use populations.”

And all the experts stress that although PrEP is an effective option, there is no 100 percent guaranteed way to prevent sexually transmitted HIV infection.

The Future of HIV/AIDS Prevention

Now that the darkest days of the AIDS crisis have passed, what does the future of treatment and prevention of HIV look like?

Dr. Mayer sees the glass as half full. “We are at an interesting point, a watershed moment where we have proof-of-concept that treating people earlier will make them less infectious, and we have proof-of-concept that for high-risk people, taking medication on a daily basis before and after high-risk behavior will make them less likely to become infected. We have new tools in the last few years, but they are not being implemented as quickly as many of us would like. It is going to take time. A lot of it is professional education in the media, a lot of it is public education, continuing the discussion.”

He adds, “None of us who work in this area think that we are going to necessarily give the same medication the same way over the next decade. There are a number of different studies looking at: Can you give less drug? Should you give different drugs that have different side effect profiles? Can you give the medication in different ways ... such as gels, vaginal rings, and injectables? It’s a very interesting time.”

Chiampas sums up the future in these words: “We think a lot of patients … will be going to their general family medicine provider and they might say, ‘I’m not positive, but I’m not in a monogamous relationship, so can I get this drug?’ or ‘My partner is HIV positive and his provider only deals with HIV patients, so can I get it through you?’ That’s where a lot of the education might be targeted.”

Finally, Dr. Mayer points out that the Centers for Disease Control and Prevention’s (CDC) guidance on the use of PrEP addresses heterosexual couples as well as women who want to conceive a child.

“One study in Africa enrolled [HIV-status] discordant heterosexual couples," he said. "It was quite a large study with almost 5,000 participants. Part of the package insert and CDC guidance is for heterosexual couples using this medication. It’s part of a larger piece. There are also studies that show that people who are infected who go on treatment become less infectious. The whole idea now is using antiretrovirals for prevention. Part of this is treating infected people earlier and working with them to maintain adherence so they are less likely to transmit."

"The other part of the equation is to identify the riskiest uninfected people and to offer them PrEP so they don’t become infected in the first place.”