[A multicenter study of efficacy and safety of oseltamivir in treatment of naturally acquired influenza].
OBJECTIVE
To evaluate the efficacy and safety of oseltamivir in the treatment of naturally acquired influenza in China.


METHODS
A randomized, double-blinded, placebo controlled trial of oseltamivir was conducted in China. Individuals of 18 to 65 years were enrolled presenting within 36 hours of influenzal symptoms and elevated temperature of 37.8 or higher. They should have at least two of the following symptoms: nasal congestion, sore throat, cough, myalgia, fatigue, headache, chill and sweating) during an influenza outbreak in the community. Individuals were randomized either to oseltamivir group (75 mg twice daily for 5 days) or placebo group.


RESULTS
A total of 478 individuals were recruited, 16(3.35%) failed to follow up or refused to continue the trial, 3 (0.6%) were excluded immediately before taking medication because they did not meet the entry criteria and 8 (1.7%) individuals were excluded in the blinding review meeting because of protocol violation. Altogether 451 individuals were analyzed for efficacy as intent-to-treat population (ITT) (216 oseltamivir, 235 placebo) and 273 individuals were identified as influenza-infected through laboratory test; they were defined as intent-to-treat infected population (ITTI) (134 oseltamivir, 139 placebo). For safety analysis, 459 individuals were included. In ITTI population, the cumulative alleviation proportion in oseltamivir group was significantly higher than that of placebo group (P = 0.046 6). The median duration of illness was 91.6 hours [95% confident interval (CI) 80.2 - 101.3 hours] in oseltamivir group and 95.0 hours (95% CI 84.5 - 105.3 hours) in placebo group. The median area under the curve (AUC) of decreased total score was significantly higher in oseltamivir group than in placebo group, being 1 382.9 and 1 236.7 score-hours respectively (P = 0.019 6). The median duration of fever and myalgia were 27.9 and 35.5 hours in oseltamivir group, being significantly shorter than that of 51.5 and 36.0 hours in placebo group (P = 0.000 1 and 0.036 1). The median AUC of decreased score for fever and nasal symptom was 337.9 and 108.5 in oseltamivir group, being significantly higher than that of 311.3 and 43.3 in placebo group (P = 0.011 8 and 0.040 3). The proportion of subjects reporting fever in oseltamivir group were significantly lower than that in placebo group at 36, 60, 72, 96, 120 and 132 hours after the initiation of treatment (P = 0.049, 0.001, 0.001, 0.007, 0.007 and 0.030). The amount of paracetamol taken, incidence of secondary complications and antibiotics usage associated with secondary complications were similar in the two groups (P = 0.085 1, 0.944, 1.000). For ITT population, similar results were seen. Adverse events reported were similar in oseltamivir and placebo group. The main adverse events were gastrointestinal symptoms, headache, vertigo, and rashes.


CONCLUSIONS
Oseltamivir was effective and well tolerated in the treatment of early naturally acquired influenza.
Li
L
L
Department of Respiratory Diseases, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing 100730, China.
Cai
B
B
Wang
M
M
Zhu
Y
Y
D000081:Acetamides / Q000008:administration & dosage / Q000627:therapeutic use*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000998:Antiviral Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007251:Influenza, Human / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D009439:Neuraminidase / Q000037:antagonists & inhibitors*; D053139:Oseltamivir
D000081:Acetamides; D000998:Antiviral Agents; D053139:Oseltamivir; D009439:Neuraminidase