Friday marks the 35th anniversary of World AIDS Day, an international moment to remember, reflect and educate people on the HIV/AIDS epidemic that started over four decades ago. But due to advancements in science, there are several tools in the market to help prevent HIV. Pre-exposure prophylaxis, known as PrEP, is a highly effective medicine that works to prevent HIV. PrEP can come in several forms, but its uptake has been slow.

Marketplace’s Sabri Ben-Achour spoke about that with Dr. Anne Neilan, an infectious disease specialist and professor at Harvard University. Below is an edited transcript of their conversation.

Sabri Ben-Achour: So, PrEP — it prevents HIV. It’s a shot. It’s a pill. How does it work?

Anne Neilan: So, there’s two daily oral fixed dose combination pills: TDF/FTC, which is also called tenofovir, disoproxil fumarate emtricitabine — a mouthful with the brand name that’s better known by Truvada. Then there’s the newer one, version of the same daily oral pill, which is emtricitabine and tenofovir alafenamide, or DESCOVY being the brand name. And then there’s injectable Cabotegravir, which is the newest option that’s available. It’s long-acting and it’s an injection once every two months. The first option that I mentioned, the oldest, the one that we’ve been using the longest TDF/FTC, there’s a way that you can take it other than just daily, which is you can take it as we call it “event-driven” or “on demand” or “two on one dosing.” You would take it around the time of a sexual event, rather than taking it continuously. So those are the three options and the four ways one can take PrEP in the United States right now,

Ben-Achour: Who is this medication for?

Neilan: So, PrEP is for people who are at increased risk of HIV and the CDC and the USPS TF [United States Preventive Services Task Force] have outlined a set of criteria. But it can be for anyone who’s at increased risk. That’s somebody who is having sex without a condom, who has had a sexually transmitted infection in the last six months, people who use injection drugs who may engage in sexual practices that put them at risk of HIV, or someone with a partner with known HIV who is not biologically suppressed. Those are some of the individuals who would be considered to benefit the most from PrEP. That being said, epidemiologic risk, meaning the sort of behaviors that put you at risk of acquiring HIV, can be really hard to determine on a longitudinal basis. These can change from hour to hour for individuals. So, another one of what we consider an eligibility criteria is somebody who considers themselves to be at increased risk for HIV, meaning that if someone comes into a clinic and says, “I really think I need PrEP,” that, you know, the clinician may not necessarily need to understand exactly why that may be, because sometimes it’s really hard to disclose those things.

Ben-Achour: PrEP has been around in one form or another for many years. Has it shown up in the data as to HIV transmission rates?

Neilan: So, PrEP has been around since 2014. And it’s just amazing to be able to offer an option to prevent HIV to patients who are at increased risk. It is really a game changer. And in the trials, the efficacy — meaning how much it prevents HIV — is really astonishing. If taken daily or if taken as prescribed, it can be up to 99% effective [daily oral PrEP]. And in fact, in the studies that looked at comparing injectable PrEP to oral PrEP, actually, injectable PrEP was even better. And in part, that was because those studies were sort of taking all comers; it didn’t look at the subset of individuals who could take PrEP daily really, really well. Because it’s really hard for anybody to take a pill daily, meaning that it is not as effective if you’re not able to take that pill daily, the oral PrEP pill.

Ben-Achour: How much does it cost to be on PrEP?

Neilan: Well, it depends on where you live and who you are and what kind of PrEP you’re taking. So, you know, if you were to look at the Mark Cuban pharmacy recently, you would see that the medication price for generic oral TDF/FTC, that option that’s been around since 2014, it’s less than 50 cents a day for that medication. But if you were going to look at the branded DESCOVY price, it would be about $18,000 annually, and Cabotegravir is north of that. What the patient bears really depends on their health insurance coverage. So it can really vary widely.

Ben-Achour: For the higher-end versions of PrEP, why are they so expensive?

Neilan: That is a great question that is not entirely transparent to those of us who’ve worked in this field for a while.  It’s often the case that newer and better drugs are priced as being more costly than their alternatives. But it’s not really clear how those prices are created. You know, oftentimes it’s cited that it’s the research and development cost that goes into it. But it’s not a transparent formula that one can Google and look up online. It’s also the case that, over time, the medications both for treating HIV and for preventing HIV, that their increase in price has exceeded that of inflation. So, the answer is I don’t know. Since I’m not there when determining the price, but it is it is astonishing, the vast cost difference, and it doesn’t necessarily correspond to value.

Ben-Achour: It makes me wonder what the market incentive is here for the newer versions of PrEP when the old one is so cheap.

Neilan: When I have a patient in front of me, right, I actually don’t really think about at all the price of medications, right — especially if they have good insurance and they’re not going to bear the cost. I counsel them through the different side effects of the different options, right. And so, you know, generic PrEP is a great option for the vast majority of people. If somebody has kidney issues or has osteopenia, meaning thin bones, then that’s a really good reason to pick the newer formulation, DESCOVY. That being said, DESCOVY’s a smaller pill. And so, for some patients, particularly the adolescents and young adults, my personal focus, they sometimes favor that. It’s also the case that they’ve read information about side effect profiles, which may be interpreted by them in a way that they may come in deciding that they want a certain formulation. I think injectable is in a different category, because it’s such a different mode of delivery. It’s incredible to have an option for patients who can’t take a pill daily, that they could get an injection.

Ben-Achour: Is price a barrier in any way to uptake of PrEP, or is maybe awareness the bigger problem?

Neilan: So, I think there are many layers of barriers to PrEP uptake. Individual and systems-wise, and the stigma that goes alongside it. One need only read the Braidwood Management Inc. v. Becerra decision by Justice O’Connor to understand some of the stigmatizing language that’s often attached to HIV pre-exposure prophylaxis. But a true root cause is price, right. So, if you have a PrEP assistance program that has a fixed budget, you can imagine that you know, $170 per patient per year is going to go a heck of a lot farther than north of $20,000 per patient per year, if that’s the price that you’re paying to get people on PrEP. At the same time, patients want to have choices. And for a lot of these modalities, taxpayer-funded research went into a lot of the studies that led to their approval for the prevention indication. And it’s not clear to me at least how that gets factored in, if at all, to the pricing.

Ben-Achour: If insurance covers it, then why is price a problem?

Neilan: So, value has to be understood in pricing relative to its alternatives. Right? And so, I guess, do we think that that injectable PrEP is worth that? I can’t even do the math in my head, how many times have a markup it is for generic PrEP, and that we should just ignore that as a society in terms of what we’re willing to pay for prevention. You know, I think it’s a problem for the health system as a whole that we should all be concerned about, if medications aren’t priced reflecting their value. If insurance covers it, sure, but there are a lot of underinsured individuals who need access to PrEP. So, I guess, for the insured patient, it is not a problem. But it sure as heck is a problem for the insurer, the insurance company, and then really it ends up trickling down to the provider and the patient. A couple of weeks ago, I was trying to get DESCOVY approved for a patient with true pill dysphagia, meaning they can’t swallow pills, they gag, they had tried injectable Cabotegravir. They didn’t tolerate it for a rare reason; it’s usually very well tolerated. And I spent 90 minutes on the phone. And why is that? It’s because DESCOVY is so much more expensive. And that’s a problem for the insurance companies. So yes, I think bottom line, I think it’s a problem.

Ben-Achour: Is it a problem with an obvious solution?

Neilan: That’s a trickier question. I think we have a lot of tools at our disposal to help us understand value. And, you know, I think there are other examples of how medications are priced in other places that we could look to. I don’t have a simple solution, but I think that we could do better.

Ben-Achour: How could we make PrEP more widely accessible? What are some things we could do?

Neilan: Well, one thing would be lowering the price of medications. And then I think, you know, we’re legislatively you know, the Braidwood Management v. Becerra threatened to overturn the Affordable Care Act coverage of PrEP without cost-sharing for patients. Right. It’s a USPSTF grade A recommendation. There aren’t many of those. We know that for individuals who are at the highest risk of HIV infection, among those include sexual minority males, men who have sex with men. Not improving access particularly to generic PrEP, really, it’s throwing away both lives and money in terms of the HIV infections that we could prevent for less than 50 cents a day.

Ben-Achour: What are some good resources that you might recommend if someone wants to learn more about HIV prevention and care.

Neilan: There’s a great organization called PrEP4All, which has a lot of patient centered resources. The U.S. Centers for Disease Control and Prevention also has some great patient-focused resources as well that you can just Google and click on the page to provide you with sort of a snapshot of what some helpful facts may be. I think those would be the two the two resources that I often refer patients to.