People who use drugs achieved high rates of hepatitis C cure
on direct-acting antiviral treatment despite ongoing drug and alcohol use,
demonstrating that active drug use should not be a barrier to treatment, US
researchers report in the journal Open Forum Infectious Diseases.
Active drug and alcohol use have disqualified people with hepatitis
C in some settings from obtaining direct-acting antiviral treatment. But there
is little evidence to support this barrier.
Researchers at the University of Colorado wanted to see
whether various methods of supporting adherence had any greater impact on
adherence to direct-acting antiviral treatment in people who were using drugs.
They recruited 60 people with hepatitis C who reported drug
or alcohol use within the previous 30 days. The study excluded people
previously treated for hepatitis C who had cirrhosis.
All participants received treatment with
ledipasvir/sofosbuvir (Harvoni) for 12 weeks.
Participants were randomised to one of two methods of
adherence support: either video monitoring of pill taking or using a wireless
pillbox (users receive a text message if they don’t open the pocket pill dispenser
each day).
The study population was predominantly male (78%), White (72%)
and HIV positive (78%). All those with HIV were taking daily HIV medication too.
Most participants had genotype 1a (65%) or 1b (22%) infection.
Study participants were asked about drug use at study visits
every two weeks and underwent urine testing for drugs.
Drug and alcohol use were common during treatment. Marijuana
use was reported at 60% of all participant study visits, methamphetamine at 37%
of visits, opioids at 22% of visits and cocaine at 17% of visits. Injecting was
reported at 20% of visits, mainly of methamphetamine (78% of injecting).
Alcohol use was reported at 56% of visits and 19% reported heavy alcohol use
during the preceding two weeks.
Eighty-six per cent of participants who started treatment achieved
a cure. Three of eight who were not cured were lost to follow-up, two were dropped
from the study for protocol violations and three were virological
non-responders or reinfected). Two of the participants lost to follow-up had
negative HCV RNA results by week 8, suggesting that they may have been
successful responders to treatment despite lack of post-treatment follow-up.
Adherence to study medication was very high; participants
took a median of 96% of doses. There was no difference in adherence rates
according to reminder method.
Multivariable analysis showed that poor adherence was
associated with Black race (odds ratio 4.09 [1.42-11.74, p=0.009), HIV co-infection
(OR 2.94 [1.37-6.32], p=0.006), cocaine use (OR 2.12 [95% CI 1.08-4.18], p=0.03)
or methamphetamine use (OR 2.51, 95% CI 1.44-4.37, p=0.001).
Although sustained virologic response was achieved by participants
with adherence rates as low as 30% in this study, the mean adherence rate in
the only case of confirmed virologic failure was 100%, but this participant had
cirrhosis.
“Our findings support expanding DAA to treat people who use
drugs to eradicate HCV and the use of technology-based measures to facilitate treatment
uptake in this population,” the researchers conclude.