Changes in risk behaviours during and following treatment for hepatitis C virus infection among people who inject drugs: The ACTIVATE study

BACKGROUND

The risk of hepatitis C virus (HCV) reinfection due to continued injecting risk behaviours might remain a barrier to HCV treatment among people who inject drugs. We aimed to evaluate changes in risk behaviours during and following HCV treatment among people with ongoing injecting drug use or receiving opioid substitution treatment (OST).

METHODS

ACTIVATE was an international multicentre clinical trial conducted between 2012 and 2014. Participants with HCV genotypes 2/3 infection were treated with peg-interferon/ribavirin for 12 or 24 weeks and completed a self-administered behavioural questionnaire at each study visit. The impact of time in treatment and follow-up on longitudinally measured recent (past month) behavioural outcomes was evaluated using generalized estimating equations.

RESULTS

Among 93 enrolled participants (83% male, median age 41 years), 55 (59%) had injected in the past month. Any injecting drug use decreased during HCV treatment and follow-up (OR 0.89 per incremental study visit; 95% CI 0.83-0.95). No significant changes were found in ≥daily injecting (OR 0.98; 95% CI 0.89-1.07), use of non-sterile needles (OR 0.94; 95% CI 0.79-1.12), sharing of injecting paraphernalia (OR 0.87; 95% CI 0.70-1.07) or non-injecting drug use (OR 1.01; 95% CI 0.92-1.10). Hazardous alcohol use decreased throughout (OR 0.56; 95% CI 0.40-0.77) and OST increased between enrolment and end of treatment (OR 1.48; 95% CI 1.07-2.04).

CONCLUSIONS

Recent injecting drug use and hazardous alcohol use decreased, while OST increased during and following HCV treatment among participants with ongoing injecting drug use. These findings support further expansion of HCV care among PWID.

Adherence to response-guided pegylated interferon and ribavirin for people who inject drugs with hepatitis C virus genotype 2/3 infection: the ACTIVATE study

BACKGROUND

The aims of this analysis were to investigate treatment completion and adherence among people with ongoing injecting drug use or receiving opioid substitution therapy (OST) in a study of response-guided therapy for chronic HCV genotypes 2/3 infection.

METHODS

ACTIVATE was a multicenter clinical trial recruited between 2012 and 2014. Participants with genotypes 2/3 were treated with directly observed peg-interferon alfa-2b (PEG-IFN) and self-administered ribavirin for 12 (undetectable HCV RNA at week 4) or 24 weeks (detectable HCV RNA at week 4). Outcomes included treatment completion, PEG-IFN adherence, ribavirin adherence, and sustained virological response (SVR, undetectable HCV RNA >12 weeks post-treatment).

RESULTS

Among 93 people treated, 59% had recently injected drugs (past month), 77% were receiving OST and 56% injected drugs during therapy. Overall, 76% completed treatment. Mean on-treatment adherence to PEG-IFN and ribavirin were 98.2% and 94.6%. Overall, 6% of participants missed >1 dose of PEG-IFN and 31% took <95% of their prescribed ribavirin., Higher treatment completion was observed among those receiving 12 vs. 24 weeks of treatment (97% vs. 46%, P < 0.001) while the proportion of participants with 95% on-treatment ribavirin adherence was similar between groups (67% vs. 72%, P = 0.664). Receiving 12 weeks of therapy was independently associated with treatment completion. No factors were associated with 95% RBV adherence. Neither recent injecting drug use at baseline nor during therapy was associated with treatment completion or adherence to ribavirin. In adjusted analysis, treatment completion was associated with SVR (aOR 23.9, 95% CI 2.9-193.8).

CONCLUSIONS

This study demonstrated a high adherence to directly observed PEG-IFN and self-administered ribavirin among people with ongoing injecting drug use or receiving OST. These data also suggest that shortening therapy from 24 to 12 weeks can lead to improved treatment completion. Treatment completion was associated with improved response to therapy. ACTIVATE trial registration number: NCT01364090 - May 31, 2011.

Low virological response and high relapse rates in hepatitis C genotype 1 patients with advanced fibrosis despite adequate therapeutic dosing

BACKGROUND & AIMS

The impact of fibrosis stage on chronic hepatitis C virus (HCV) treatment response was explored in CHARIOT, a study of high dose peginterferon alfa-2a (PEG-IFNalpha-2a) induction therapy in treatment naïve genotype 1 infection.

METHODS

Eight hundred and ninety-six patients were randomised 1:1 to 360 microg (n=448) or 180 microg (n=448) PEG-IFNalpha-2a weekly with RBV 1000-1200 mg/day for 12 weeks followed by 36 weeks of 180 microg PEG-IFNalpha-2a weekly plus RBV 1000-1200 mg/day. Virological responses were assessed at week 4, 8, 12, 24, 48 (end of therapy), and 24 weeks following therapy (sustained virological response, SVR). As previously reported, there was no significant difference in SVR in the induction (53%) and standard (50%) arms, therefore the pooled study population was used for analysis of SVR and relapse.

RESULTS

A marked step-wise decline in SVR was evident by fibrosis stage: F0 (70%); F1 (60%); F2 (51%); F3 (31%); F4 (10%) (p<0.0001). Early virological responses were lower among F3/4 patients, including rapid virological response (RVR) (21% vs. 34% for F3/4 and F0-2, respectively) (p=0.0072), and the RVR positive predictive value was also lower (63% vs. 80%). Virological relapse rates were similar in early disease stages (F0, 16%; F1, 23%; F2, 26%), but increased markedly in advanced fibrosis (F3, 50%; F4, 80%) (p<0.0001). Cumulative PEG-IFNalpha-2a and ribavirin doses were similar among patients with F3/4 and F0-2 within treatment arms through week 4, 8, 12, and week 24.

CONCLUSIONS

Low virological response in hepatitis C genotype 1 patients with advanced fibrosis is not explained by inadequate cumulative PEG-IFN and ribavirin doses.

Nervous control of light responses in the sea anemone, Calamactis praelongus

1. The burrowing sea anemone, Calamactis praelongus, responds to light with local, non-nervous contractions of the column. There are also more extensive responses of the column and retractor muscles co-ordinated by nerve net pulses (NNP's) under pacemaker control. 2. NNP's occur in at least two types of bursts and in sequences which sometimes indicate a rotating site of pulse initiation. 3. Light-evoked NNP sequences can be tape recorded and used later to drive a stimulator to reproduce the original sequences in the same or different anemones, evoking muscular responses which approximate the originals. This technique separates the pacemaker-directed component of the light response from the local effects of light stimulation. 4. Isolated circular and parietal muscles contract slowly when stimulated by light or excited indirectly by NNP's. Retractor muscles are insensitive to light but produce rapid contractions when excited by closely spaced light-evoked NNP's. 5. A model for light responses is proposed which incorporates the characteristics of isolated muscles and intact anemones.