【新知】Is PrEP making a difference? Top HIV researchers provide answers

July 23, 2017, by Emily Newman

BETA is attending and reporting from the 2017 International AIDS Society conference on HIV Science this week in Paris, France from July 23 to 26—bringing you the latest news, updates, and research on HIV treatment and prevention.

As countries, cities and agencies worldwide ramp up their investment in pre-exposure prophylaxis (PrEP) services for people at risk for HIV, many are wondering: Is this strategy working in the “real world”—outside the safe parameters of clinical trials?

At the International AIDS Society conference this week, three researchers offered evidence to this point. Here’s what we learned about how the scale-up of PrEP health services (along with other PrEP awareness and educational campaigns) is helping to reduce the number of new HIV infections in communities and countries around the world.

London clinic sees HIV infections decline 42% with PrEP

PrEP scale-up and advocacy has been ongoing in England since 2015, when results from the PROUD clinical study in England revealed an 86% reduction in HIV infections among people taking PrEP. The 56 Dean Street clinic began providing people who wanted to start PrEP with advice and medical monitoring in 2015, and two critical websites were launched in the U.K. to raise awareness about PrEP and give people information on how to purchase the medication used for PrEP.

Although the cost of PrEP medications was not (and still is not) covered by the country’s National Health Service, Sheena McCormack, from University College London, said that “things were already on the move, in a big way.” People were finding out about PrEP, and accessing it on their own—even if it meant buying it from unverified sources online. (The 56 Dean Street Clinic counsels people who buy PrEP medication online and supervise its  use.)

Now, McCormack estimates, using data supplied by the hookup app Grindr, that about 6,000 men who have sex with men in the U.K. are now using PrEP (based on data from April 2017).

As PrEP has become more widely used, the number of HIV infections diagnosed at 56 Dean Street has decreased—even as the number of tests provided has increased, said McCormack.

Between 2015 and 2016, the clinic saw a 42% decline in HIV infections (there were 679 HIV diagnoses in 2015 and 394 in 2016).  “We were seeing between 55 and 70 [HIV infections] a month and now we’re down to about 15 to 20. And that has sustained,” she said.

New South Wales, Australia, sees a 43% decline in early-stage HIV infections

With a goal to reach 90% of all gay and bisexual men at high risk for HIV with PrEP, and results that exceeded this level, the state of New South Wales is a stunning example of a successful PrEP roll-out.

“Our conservative estimate of [the number of gay and bisexual men needing PrEP] was about 3,700,” said Andrew Grulich, of University of New South Wales. “As of today, we have more than 6,500 men on PrEP in the state of New South Wales.”

Most of the people taking PrEP are gay and bisexual men (Grulich said that their programs do not use the term “men who have sex with men” in order to purposefully acknowledge the gay community) with high rates of gonorrhea and chlamydia. In previous research, this high-risk population was estimated to have HIV prevalence rates between 5% and 15%.

Since the scale up of PrEP in New South Wales, HIV incidence rates have declined. The incidence rate of early HIV infections in the first quarter of 2017 was 43% less than the average over the previous five  years.

Grulich explained that his team defined “early HIV infections” as people who received an HIV diagnosis with a documented negative HIV test in the previous year or who had a documented diagnosis of seroconversions illness in the same time frame.

“We are very, very encouraged by [this reduction in HIV incidence], obviously, but we do think we need a few more quarters of data before we get too excited by it,” said Grulich. So far, there have been no HIV seroconversions among anyone taking PrEP in this program.

Grulich said that there was quite a bit of awareness building needed in order to  ensure that people who could benefit from PrEP knew about it and were enticed to find out more about it. The state launched highly-visible publicity campaigns advertising HIV prevention options including PrEP. They held public information sessions with Robert Grant, MD, MPH, the principal investigator for the PrEP iPrEx study to create demand for PrEP.

“We told our health departments that PrEP was absolutely necessary. Not an option, but a critical and necessary part of the response,” said Grulich.

Real-world PrEP use in France keeps HIV rates low  

Jean-Michel Molina, from the Saint-Louis Hospital, University of Paris Diderot, shared data from France, where PrEP has been approved and fully reimbursed by the health system since January of 2016.

From January 2016 to February 2017, nearly 3,000 people registered for PrEP. Most were men who have sex with men (98%) and at “high risk” for HIV as indicated by the percentage of PrEP clients who reported chemsex (23%), sexually transmitted infections in the previous 12 months (36%) and post-exposure prophylaxis (PEP) in the previous 12 months (11%).

So far there have been only four HIV seroconversions among people accessing PrEP (two people seroconverted before starting the PrEP medication), and the HIV incidence rate has been very low.

“When you look at the overall [HIV] incidence in this cohort, it actually very similar to that of what we saw in the open label extension of IPERGAY (the clinical trial of on-demand PrEP)—0.28 per hundred person years of follow up,” said Molina. (People in the placebo part of the IPERGAY study had an HIV incidence rate that was much higher, at 6.6 per 100 person years.)

Uptake of PrEP in France has been bolstered by a few important factors, including political support from the city of Paris and other government officials, full medication reimbursement through the national health system and awareness campaigns launched by the Ministry of Health in Paris and throughout the country.

“Now, we need to  monitor PrEP implementation and we hope to demonstrate shortly that implementing PrEP will have a public health benefit in terms of curbing the HIV epidemic,” said Molina.

Are sexually transmitted infections increasing?

Grulich and McCormack addressed a common concern about PrEP: that it will decrease condom use and lead to increases in sexually transmitted infections (STIs). Both Grulich and McCormack explained that the rates of STIs in the populations they were studying were already high, but that it didn’t seem that PrEP use was leading to any increases.

McCormack showed data from 56 Dean Street, which rolled out an “express” clinic in 2014 which led to an increase the total number of STI tests the clinic was able to perform.

“You see what an impact that had on the number of tests performed. But what’s really important to realize is that the proportion of those who were actually positive does not change,” said McCormack.

She went on to explain that in many places, PrEP clinics open and begin doing asymptomatic STI testing, and end up detecting infections that would be otherwise missed if that person weren’t accessing PrEP services.

“What I’m trying to tell you is that if you’re seeing an increased number of STIs it’s probably because you’ve been missing them before,” she said.

“Just because you’re diagnosing more STIs with PrEP is rolled out, doesn’t mean that incidence of disease is increasing,” said Grulich.

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Get more information about PrEP services offered by San Francisco AIDS Foundation at Strut, or find a PrEP-friendly provider near you. 

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