Favipiravir Treatment of Uncomplicated Influenza in Adults: Results of Two Phase 3, Randomized, Double-Blind, Placebo-Controlled Trials.

BACKGROUND: We conducted double-blind, placebo-controlled trials assessing the efficacy and tolerability of favipiravir in acute influenza. METHODS: Otherwise healthy adults with influenza-like symptoms and fever of ≤48 hours were randomized to favipiravir (1800 mg twice daily [BID] on day 1, 800 mg BID on days 2-5) or placebo tablets (1:1 in US316; 3:1 in US317). The primary efficacy endpoint was the time to illness alleviation when 6 influenza symptoms were self-rated as absent or mild and fever was absent in the intention-to-treat, influenza-infected participants. RESULTS: In US316 (301 favipiravir, 322 placebo), favipiravir was associated with a 14.4-hour reduction (median, 84.2 vs 98.6 hours; P = .004) in time to illness alleviation vs placebo. In US317 (526 favipiravir, 169 placebo), favipiravir did not significantly reduce time to alleviation (median, 77.8 vs 83.9 hours). In both trials favipiravir was associated with reduced viral titers, RNA load area under the curve over days 1-5, and median times to cessation of virus detection (P < .001). Aside from asymptomatic hyperuricemia, no important differences in adverse events were found. CONCLUSIONS: This favipiravir dosing regimen demonstrated significant antiviral efficacy but inconsistent illness alleviation in uncomplicated influenza. Studies of higher doses and antiviral combinations for treating serious influenza and other RNA viral infections are warranted. Clinical Trials Registration. NCT02026349; NCT02008344.

A single administration of recombinant human interleukin-12 is associated with increased expression levels of interferon-gamma and signal transducer and activator of transcription in healthy subjects.

The objectives of this study were to assess the safety and tolerability of single doses of 1, 4, and 8 mug of recombinant human interleukin-12 (rhIL-12) administered subcutaneously to healthy subjects. The pharmacokinetics, pharmacodynamics, and pharmacogenomics of rhIL-12 were evaluated. Recombinant human IL-12 was well tolerated in these healthy male and female subjects. The most frequently reported adverse events were flu-like symptoms, which exhibited a dose-response relationship. Pharmacokinetic analysis suggested that serum IL-12 levels increased with dose. Analysis of serum levels indicated that interferon-gamma increased with the dose of rhIL-12, whereas IL-6 levels showed no changes with rhIL-12 treatment. The messenger ribonucleic acid expression of signal transducer and activator of transcription was significantly increased 24 hours after the administration of rhIL-12 for all dose groups versus placebo, and results indicated that the magnitude of increase may be dose dependent. This study suggests that interferon-gamma and signal transducer and activator of transcription are biomarkers of rhIL-12 activity.

Multiple-dose, safety, pharmacokinetics, and pharmacodynamics of a new selective estrogen receptor modulator, ERA-923, in healthy postmenopausal women.

ERA-923 is a new selective estrogen receptor modulator under clinical investigation for use in tamoxifen refractory metastatic breast cancer. This study evaluated the safety, tolerability, pharmacokinetics, and pharmacodynamics of once-daily oral ERA-923 (10-200 mg) for 28 days in healthy postmenopausal females. ERA-923 was well tolerated, and adverse events were mild and reversible. No clinically significant changes in laboratory values were found with ERA-923 versus placebo. ERA-923 appeared to undergo extensive metabolism and enterohepatic recirculation. In addition, pharmacokinetic analysis showed that a high-fat breakfast increased the extent of absorption. ERA-923-dosed subjects had no uterine or ovarian changes when evaluated with transvaginal ultrasound and compared to placebo subjects. Overall, ERA-923 was safe and well tolerated in postmenopausal women dosed for 28 days.

A multiple-dose, safety, tolerability, pharmacokinetics and pharmacodynamic study of oral recombinant human interleukin-11 (oprelvekin).

A study in healthy men and women was performed to assess the safety, tolerability, pharmacokinetics (PK) and pharmacodynamics (PD) of orally administered recombinant human interleukin-11 (oprelvekin) (OAO). Four cohorts of 10 subjects each received 3, 5, 10 or 30 mg (8:2/OAO:placebo ratio), first as a single dose with a 7-day washout period, then 7 consecutive daily doses. Safety was assessed by ongoing evaluation of adverse events (AEs) and laboratory values. PK samples were collected on the first and last day of dose administration. The established effects of subcutaneous oprelvekin on C-reactive protein (CRP, upward arrow), platelet count (upward arrow), fibrinogen (upward arrow) and hemoglobin (downward arrow), were evaluated. PK analysis showed that most subjects (27/34, 79%) had undetectable serum levels of IL-11. PD measures showed no changes from baseline between any OAO group and the placebo group. Orally administered oprelvekin was safe and well tolerated at all doses. A total of five AEs (abdominal pain, diarrhea, headache, rhinitis, grade 3 alanine aminotransferase elevation) were reported across all groups. Evaluations of serum IL-11 levels indicate that OAO is not systemically absorbed at levels above the lower limit of the bioanalytic assay. These data in addition to the lack of effect on PD measures suggest that there is a decreased potential of systemic adverse events with OAO.