Authors' objectives:

The aims of this report are: (1) To perform a systematic review of published and unpublished clinical studies to assess and quantify, using a meta-analysis if appropriate, the efficacy and effectivenessa of oseltamivir in individuals who are suspected of having influenza; and (2) to assess the cost-effectiveness of treating suspected influenza with oseltamivir in a primary care setting where standard treatment is no active medical intervention.

Authors' results and conclusions: Of 117 references identified, six trials with 1735 participants met the inclusion criteria of which 469 individuals were individuals at risk for developing complications. All six trials were sponsored by industry and were of a generally high quality. Oseltamivir treatment resulted in an absolute reduction of 1% and 2% for a combined outcome of death, hospitalization, and complications of illness in otherwise-healthy and at-risk individuals, respectively, suspected of having influenza. The results for these three outcomes separately were similarly small and statistically insignificant. In one trial involving 419 participants, oseltamivir reduced the median time to return to normal activity by 57 hrs when compared with placebo.

Authors' recommendations: There is insufficient evidence that oseltamivir reduces complications, hospitalizations and/or death in individuals suspected of having influenza. In addition, there is insufficient evidence of any benefit in individuals with suspected influenza who are at risk for developing complications. Evidence from one trial suggests that otherwise healthy individuals suspected of having influenza, return to normal activity faster when treated with oseltamivir than those receiving placebo. No studies are available to compare the magnitude of this benefit to amantadine, zanamivir or symptom-relieving medications. The economic analysis suggests that, from a government payer perspective, oseltamivir is unlikely to be cost-effective for treating suspected influenza in otherwise healthy adults, based on reasonable assumptions about diagnostic accuracy in a primary care setting when influenza is circulating in the community. It would appear that oseltamivir is also unlikely to be a cost-effective treatment for adults at risk of developing influenza-related complications - but the clinical evidence for this is inconclusive at this time. Another cause for concern is the likelihood of primary care consultations from patients with little risk of complications who would not otherwise seek treatment. If oseltamivir were to be reimbursed by a government payer, additional budgetary resources would have to be allocated since it is unlikely to be a cost-saving strategy.

Authors' methods: Systematic review, economic evaluation

Project Status: Completed

URL for project: https://www.ccohta.ca/

Year Published: 2001

English language abstract: An English language summary is available

Publication Type: Not Assigned

Country: Canada

Organisation Name: Canadian Coordinating Office for Health Technology Assessment

Contact Address: 600-865 Carling Avenue, Ottawa, ON K1S 5S8 Canada. Tel: +1 613 226 2553, Fax: +1 613 226 5392;

Contact Name: requests@cadth.ca

Contact Email: requests@cadth.ca

Copyright: Canadian Coordinating Office for Health Technology Assessment (CCOHTA)