Understanding the effect of the HCV polymerase inhibitor mericitabine on early viral kinetics in the phase 2 JUMP-C and PROPEL studies.

AIMS: The aim was to evaluate early viral kinetics in patients receiving mericitabine [hepatitis C virus (HCV) nucleoside polymerase inhibitor] with peginterferon alfa-2a (40KD) and ribavirin in two clinical trials (PROPEL and JUMP-C). METHODS: We examined rapid virological responses (RVRs; week 4 HCV RNA <15 IU ml(-1) ) and complete early virological responses (cEVR; week 12 HCV RNA <15 IU ml(-1) ) in HCV genotype 1/4-infected patients receiving mericitabine (500 or 1000 mg) or placebo twice daily plus peginterferon alfa-2a and ribavirin. RESULTS: Among IL28B rs12979860 CC genotype patients receiving 500 or 1000 mg mericitabine or placebo, respectively, RVR rates were 64.3% (95% confidence interval: 38.8-83.7%), 95.1% (83.9-98.7%) and 33.3% (20.2-49.7%), and cEVR rates were 100% (78.5-100%), 100% (91.4-100%) and 80.6% (65.0-90.3%). Among non-CC genotype patients, RVR rates were 26.5% (14.6-43.1%), 52.3% (43.0-61.3%) and 5.7% (2.2-13.8%), and cEVR rates were 76.5% (60.0-87.6%), 84.6% (76.6-90.1%) and 28.6% (19.3-40.1%), respectively. In multiple regression analysis, IL28B genotype (P < 0.0001), mericitabine dose (P < 0.0001) and bodyweight (P = 0.0009) were associated with first-phase (α) slope (change in log10 HCV RNA from baseline to week 1). CONCLUSIONS: Mericitabine-containing triple therapy reduces the impact of IL28B genotype on RVR and cEVR compared with peginterferon alfa-2a and ribavirin dual therapy. The IL28B genotype, mericitabine dose and bodyweight are the most important factors associated with the α slope, and there is no evidence of a pharmacokinetic drug-drug interaction between mericitabine and ribavirin.

Combining baloxavir marboxil with standard-of-care neuraminidase inhibitor in patients hospitalised with severe influenza (FLAGSTONE): a randomised, parallel-group, double-blind, placebo-controlled, superiority trial.

BACKGROUND: Neuraminidase inhibitors (NAIs) are considered the standard of care for hospitalised patients with influenza. We aimed to test whether combining the cap-dependent endonuclease inhibitor baloxavir marboxil (hereafter baloxavir) with standard-of-care NAIs would result in improved clinical outcomes compared with NAI monotherapy in hospitalised patients with severe influenza. METHODS: We did a randomised, parallel-group, double-blind, placebo-controlled, superiority trial. Patients aged 12 years or older who were hospitalised with laboratory-confirmed influenza (by RT-PCR or a rapid test) and had a National Early Warning Score 2 (NEWS2) of 4 or greater were included. Recruitment took place in 124 centres across 25 countries. Using a permuted-block method and an interactive response system, patients were randomly assigned (2:1) to receive either baloxavir plus NAIs (hereafter the baloxavir group) or placebo plus NAIs (hereafter the control group). Participants, investigators, and those assessing outcomes were masked to group assignment. Baloxavir was administered orally on day 1 and day 4 (40 mg for bodyweight <80 kg, or 80 mg for ≥80 kg), and on day 7 if no clinical improvement had occurred by day 5. The NAIs included in this study were oseltamivir, zanamivir, and peramivir, which were selected and administered according to local standard practice. The primary endpoint was time to clinical improvement, defined as time to a NEWS2 of 2 or lower for 24 h or hospital discharge, whichever came first, based on daily assessments over the study duration of 35 days. Secondary endpoints included safety analyses. The modified intention-to-treat infected (mITTI) population (ie, all patients who were randomly assigned to treatment, received a dose of study drug, and were RT-PCR-positive for influenza at any timepoint according to the treatment assigned at randomisation) was used in all efficacy analyses. The safety population (ie, all patients who received at least one dose of study treatment, according to the treatment received) was used in the safety analyses. The trial is registered with ClinicalTrials.gov, NCT03684044. FINDINGS: Overall, 366 patients were enrolled between Jan 8, 2019, and March 16, 2020, of whom 241 were assigned to the baloxavir group and 125 to the control group. The mITTI population comprised 322 patients, 208 in the baloxivir group and 114 in the control group. In total, 280 (87%) of these patients had influenza A infections. Median time to clinical improvement was 97·5 h (95% CI 75·9 to 117·2) in the baloxavir group and 100·2 h (75·9 to 144·4) in the control group (median difference -2·7 h [95% CI -53·4 to 25·9], p=0·467). Baloxavir plus NAI was well tolerated, and no new safety signals were observed; serious adverse events occurred in 29 (12%) of 239 patients in the baloxavir group versus 19 (15%) of 124 patients in the control group, of which one was considered related to treatment (orthostatic hypotension in a patient in the control group). Overall, four deaths (2%) occurred in the baloxavir group and seven (6%) in the control group; none were considered related to treatment. INTERPRETATION: Combining baloxavir with NAIs did not result in superior clinical outcomes compared with NAIs alone. The combination of baloxavir plus NAI was well tolerated. The findings suggest that combination antivirals would not be routinely indicated in clinical practice for hospitalised patients with severe influenza. FUNDING: F Hoffmann-La Roche and the Biomedical Advanced Research and Development Authority.

Peginterferon-alpha2a and ribavirin combination therapy in chronic hepatitis C: a randomized study of treatment duration and ribavirin dose.

BACKGROUND: Treatment with pegylated interferon (peginterferon) and ribavirin for 48 weeks is more effective than conventional interferon and ribavirin in patients with chronic hepatitis C. OBJECTIVE: To assess the efficacy and safety of 24 or 48 weeks of treatment with peginterferon-alpha2a plus a low or standard dose of ribavirin. DESIGN: Randomized, double-blind trial. SETTING: 99 international centers. PATIENTS: 1311 patients with chronic hepatitis C. INTERVENTION: Peginterferon-alpha2a, 180 microg/wk, for 24 or 48 weeks plus a low-dose (800 mg/d) or standard weight-based dose (1000 or 1200 mg/d) of ribavirin. MEASUREMENT: Sustained virologic response: undetectable HCV RNA concentration at the end of treatment and during 12 to 24 weeks of follow-up. RESULTS: Overall and in patients infected with HCV genotype 1, 48 weeks of treatment was statistically superior to 24 weeks and standard-dose ribavirin was statistically superior to low-dose ribavirin. In patients with HCV genotype 1, absolute differences in sustained virologic response rates between 48 and 24 weeks of treatment were 11.2% (95% CI, 3.6% to 18.9%) and 11.9% (CI, 4.7% to 18.9%), respectively, between standard- and low-dose ribavirin. Sustained virologic response rates for peginterferon-alpha2a and standard-dose ribavirin for 48 weeks were 63% (CI, 59% to 68%) overall and 52% (CI, 46% to 58%) in patients with HCV genotype 1. In patients with HCV genotypes 2 or 3, the sustained virologic response rates in the 4 treatment groups were not statistically significantly different. CONCLUSION: Treatment with peginterferon-alpha2a and ribavirin may be individualized by genotype. Patients with HCV genotype 1 require treatment for 48 weeks and a standard dose of ribavirin; those with HCV genotypes 2 or 3 seem to be adequately treated with a low dose of ribavirin for 24 weeks.

Early identification of HCV genotype 1 patients responding to 24 weeks peginterferon alpha-2a (40 kd)/ribavirin therapy.

Approximately one third of hepatitis C virus (HCV) genotype 1 patients achieved a sustained virological response (SVR) after 24 weeks of treatment with peginterferon alpha-2a (40 kd) plus ribavirin in a randomized, multinational trial. We aimed to identify factors associated with a rapid virological response (RVR) at week 4 (HCV RNA <50 IU/mL) and a SVR (HCV RNA <50 IU/mL at the end of follow-up) in these patients. Stepwise multiple logistic regression analysis was used to explore the prognostic factors for a RVR and SVR in genotype 1 patients treated for 24 weeks. Fifty-one of 216 (24%) genotype 1 patients in the 24-week treatment groups had a RVR. SVR rates were considerably higher in patients with than without [corrected] a RVR (89% vs. 19%, respectively). Patients with a baseline HCV RNA of less than 200,000 IU/mL (OR 9.7, 95% CI 4.2-22.5; P < .0001) or 200,000-600,000 IU/mL (OR 5.6, 95% CI 1.5-9.1; P = .0057) were more likely to achieve a RVR than those with HCV RNA greater than 600,000 IU/mL. HCV subtype (1b vs. 1a) was also independently associated with RVR (OR 1.8, 95% CI 0.9-3.7; P = .0954). RVR (OR 23.7 vs. no RVR, 95% CI 9.1-61.7) and baseline HCV RNA less than 200,000 IU/mL (OR 2.7 vs. > 600,000 IU/mL, 95% CI 1.1-6.3; P < .026) were significant and independent predictors of SVR in patients treated for 24 weeks. In conclusion, patients infected with HCV genotype 1 and treated with peginterferon alpha-2a/ribavirin sustained a RVR 24% of the time. This portends an 89% probability of a SVR after 24 weeks of treatment.