Search

The article presents a randomized controlled trial that examined the safety, immunogenicity, and efficacy of a trivalent influenza virus hemagglutinin vaccine that was produced in insect cells using recombinant baculoviruses. The authors of the study found that the vaccine was safe and immunogenic in a healthy population of adults. They also found preliminary evidence that showed the vaccine had a protective effect against a drifted influenza A virus. The inclusion of a neuraminidase component was not required for the protective effect.

Reports on a randomized controlled trial to evaluate the efficacy and safety of the oral neuraminidase inhibitor oseltamivir in the treatment of naturally acquired influenza infection. Design; Setting; Participants; Interventions; Main outcome measures; Results; Conclusions.

Context: Influenza virus neuraminidase is thought to be essential for virus replication in humans; however, to date, available neuraminidase inhibitors are limited to zanamivir, which is topically administered.Objective: To determine the safety, tolerability, and antiviral activity of oral neuraminidase inhibitor oseltamivir (GS4104/Ro64-0796) for prevention and the early treatment of influenza in experimentally infected humans.Design: Two randomized, double-blind, placebo-controlled trials conducted between June and July 1997.Setting: Individual hotel rooms; 2 large US university medical schools.Participants: A total of 117 healthy adult volunteers (aged 18-40 years; median age, 21 years) who were susceptible (hemagglutination-inhibition antibody titer < or =1:8).Interventions: All subjects were inoculated intranasally with influenza A/Texas/36/91 (H1N1) virus. For the prophylaxis study, oral oseltamivir (100 mg once daily [n = 12], 100 mg twice daily [n = 12], or matching placebo [n = 13], starting 26 hours before virus inoculation) was administered. For the treatment study, the same drug was given (20 mg, 100 mg, or 200 mg twice daily, 200 mg once daily, or matching placebo [n = 16], in each group starting 28 hours after inoculation). All regimens were continued for 5 days.Main Outcome Measures: Comparing placebo groups with pooled treatment groups, for prophylaxis, outcomes included frequency of infection and viral shedding; for treatment, viral shedding in titers.Results: In the prophylaxis study, 8 (67%) of 12 placebo and 8 (38%) of 21 oseltamivir recipients became infected (P = .16; efficacy, 61%); 6 (50%) placebo compared with 0 oseltamivir recipients shed virus (P<.001; efficacy, 100%), and 33% of placebo but no oseltamivir recipient had infection-related respiratory illness (P<.01). Among infected subjects in the treatment study (n = 69), the viral titer area under the curve of the combined oseltamivir groups (n = 56) was lower (median [interquartile range [IQR]], 80 [23-151] vs 273 [79-306] log10 tissue culture-infective doses50 per milliliter x hour; P = .02) than the placebo group (n = 13), and the median (IQR) duration of viral shedding with therapy was reduced from 107 (83-131) to 58 (35-59) hours (P = .003). Oseltamivir treatment also reduced symptom scores (median [IQR] score-hours, 225 [97-349] vs 400 [189-645]; P = .05), and nasal proinflammatory cytokine levels. Transient mild to moderate nausea after dosing was observed in 15 (17%) of 88 oseltamivir and 2 (7%) of 29 placebo recipients (95% confidence interval for difference, -11% to 68%), which was largely prevented by ingestion with food.Conclusions: In these trials, prophylaxis and early treatment with oral oseltamivir were both associated with significant antiviral and clinical effects in experimental human influenza. [ABSTRACT FROM AUTHOR]

Evaluates whether intranasal administration of the sialic acid analog 4-guanidino-Neu5Ac2en (GG167), an inhibitor of influenza virus neuraminidase, was effective and safe in either preventing or treating experimental human influenza. Evaluation of the therapeutic effects of GG167; Frequencies of local nasal intolerance.

The author emphasizes the need to expand the options for addressing pandemic influenza. He cites the limitation of vaccination in preventing pandemic influenza. He discuss two reports that offer information on pandemic influenza prevention, including a randomized clinical trial involving patients who received influenza A/Shanghai/2/13 (H7N9) inactivated virus vaccine intramuscularly. He also cites the need to do further research on hemagglutinin inhibition and neutralizing antibody.