New Zealand’s Medsafe Medicines Committee rejects Cochrane review findings

Announcement Date: September 1, 2014

New Zealand Medicines and Medical Devices Safety Authority Medicines Adverse Reaction Committee. Oseltamivir (Tamiflu) for Influenza. 11 September 2014. Released 14 November 2014 through FOI request lodged by Dr Ron Law

3.2.5 Oseltamivir (Tamiflu) for influenza


A recently published meta-analysis stimulated media interest in the use of oseltamivir. The media interest was particularly focussed on usefulness of the reserves of oseltamivir held by District Health Boards (DHBs) and the Ministry of Health for use during an influenza pandemic.

The publication of the meta-analysis by Jefferson et al in the British Medical Journal (BMJ) formed the basis of this report. Additional information on efficacy was also provided from other sources for context.

The purpose of this report was to provide the Committee with a summary of information from these published articles.


The Committee discussed the meta-analysis by Jefferson et al. It was noted that there were significant limitations to this analysis. Most significantly the authors themselves state that the large amount of data was overwhelming. The analysis was not transparent, for example the inclusion and exclusion criteria for the meta-analysis were not clear.

The Committee noted that the findings from this meta-analysis did not contradict information that is already included in the oseltamivir (Tamiflu) data sheet. In addition, this meta-analysis should be considered in the context of other similar meta-analyses assessing the efficacy and safety of oseltamivir.

The Committee also noted that the meta-analysis on reducing mortality by Muthuri et al showed that neuraminidase inhibitor treatment was associated with reduced mortality in adult patients admitted to hospital.

Overall, the Committee considered that although the benefit is modest, the risk of harm is also modest. The balance of benefits and risks for oseltamivir remains positive.

Recommendation 8

The Committee recommended that no action or advice is required regarding the safety and effectiveness of oseltamivir as a result of the publication of the meta-analysis by Jefferson et al.

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