New HCV infection less common in MSM initiating PrEP
BOSTON — New incidences of hepatitis C virus infection among men who have sex with men, or MSM, who are actively using pre-exposure prophylaxis for HIV prevention appeared to be less common than previously shown, according to data presented at The Liver Meeting 2019.
“There have been a number of studies showing that once pre-exposure prophylaxis for HIV became available, risk-taking associated with sexual transmission and previously associated with trying to reduce the risk of HIV transmission started to go down,” Jordan J. Feld, MD, MPH, FAASLD, from the University of Toronto University Health Network, said during a press conference highlighting the finds. “And so, PrEP clinics have reported high incidences of acute HCV infection both through sexual transmission and through drug use at the time associated with sex.”
As a result, the researchers aimed to assess the prevalence and incidence of HCV infections among HIV-negative individuals beginning PrEP for HIV prevention.
Additionally, the researchers aimed to determine risk factors associated with HCV acquisition.
Between October 2014 and September 2019, the incidence of HCV and bacterial sexually transmitted infections (STIs) were calculated among HIV-negative patients receiving PrEP at the University Health Network HIV Prevention Clinic in Toronto.
Oral and anal swabs, as well as urine samples were collected to test for Chlamydia trachomatis/Neisseria gonorrhoeae and blood was drawn to test for HIV, syphilis, and anti-HCV antibodies, every 3 months while on PrEP.
The retrospective cohort study comprised 344 patients (median age, 35 years; 86% MSM; 96% biological male sex) uninfected with HIV and receiving PrEP.
Five individuals tested positive for HCV antibody when PrEP began, but all had previously been treated and cured.
Serological and virologic follow-up was available for 199 HCV-negative individuals. Two infections were recorded over 282 patient-years, which yielded an incidence of primary HCV infection of 0.7 per 100 patient-years (95% CI, 0.1-2.5).
In contrast, the incidence rates of chlamydia (49.2/100 patient-years), gonorrhea (36.3/100 patient-years), and syphilis (5.2/100 patient-years) were notably higher, with the total bacterial STI rate of 49.2 per 100 patient-years (95% CI, 38-61; comparison P < .001).
Because of the relatively small numbers, the researchers were unable to assess risk factors for HCV acquisition.
“The key message from this study is that fortunately we saw low incidence of acute hepatitis C infection in primarily men receiving pre-exposure prophylaxis for HIV and this was reassuring,” Feld said. “We still feel that it’s important to screen, certainly at baseline, and then to have ongoing screening because the two [HCV-positive] individuals were found purely by screening. They were asymptomatic and had normal liver enzymes at the time ... and both of them went on to be treated, [which is] important for both their own health, but also because of unintentional transmission that could occur.” – by Ryan McDonald
Reference: Tabatabavakili T, et al. Abstract 281. Presented at: The Liver Meeting; Nov. 7-12, 2019; Boston.
Disclosure: Feld reports receiving grant or research support, and serving as a consultant for Abbott, AbbVie, Enanta, Gilead, Janssen, Merck and Roche.