Real-world hepatitis C treatment outcomes among people who inject drugs at the Stockholm needle exchange program, Sweden

The Stockholm needle exchange program (NEP) has since the start in 2013 enrolled over 4,000 participants. Annually, around 1,800 persons make 25,000 visits. 43% inject mainly heroin and 43% amphetamine. Mean age is 39 years and mean duration of injection drug use (IDU) is 18 years. 21% are homeless. In 2017, before hepatitis C (HCV) treatment was implemented, HCV prevalence among NEP participants was 55% % and HCV incidence high, corresponding to an incidence rate of 22/100 person years (PY).

All NEP participants that initiated HCV treatment between October 2017 and June 2020 were HCV RNA tested at end of treatment (EOT) and twelve weeks after EOT to confirm cure (SVR). All successfully treated participants were prospectively tested every six months and followed to the last negative HCV-RNA test or a subsequent reinfection, until October 31st 2021.

162 participants (56% amphetamine users) initiated HCV treatment. 88% were HCV-RNA negative at EOT (19 participants dropped out before EOT). Drop-out was associated with amphetamine use (p<0.05), and consequently also not being in an opioid agonist treatment (OAT) program (p<0.05). Overall, 86% reached SVR. During follow-up, there were a total of 17 reinfections corresponding to a reinfection rate of 9.3/100 PY (follow-up time of 462 PY, with a mean individual follow-up time of 1.4 PY). Factors associated with reinfection was younger age (p<0.001), treatment while in prison (p<0.01), homelessness (p<0.05) and shorter duration of IDU (p<0.0001).

A high prevalence of HCV and amphetamine use (not eligible for effective substance use treatment, such as OAT) constitutes a great challenge for HCV elimination. However, our data show promising results with high levels of cure and manageable levels of reinfections. The combined effect of sterile injection equipment distribution and HCV treatment at the NEP has reduced overall HCV prevalence to 30% in 2021.