Authors' objectives:

This report aims to evaluate the efficacy and safety of two leukotriene receptor antagonists (LTRAs) montelukast and zafirlukast, which have been marketed in Canada since 1998 and 1997 respectively, for chronic use with mild-to-moderate forms of chronic or recurrent asthma in individuals at least six years of age (for montelukast) and 12 years of age (for zafirlukast).

Authors' recommendations: The circumstances surrounding the present review have made it inappropriate to provide guidance concerning the relative (to inhaled corticosteroids (ICs)) utility of the two LTRAs for clinicians, for potential recipients of LTRAs within clinical case management and clinical research settings, for policymakers. The results of the qualitative summaries of information concerning population, intervention, and trial method characteristics are sufficiently problematic to preclude their generalizability. The missing, limited or suspect population characteristic information which contributed to the decision to relax some relevance criteria to allow completion of this review, has yielded an unclear sense as to whom the results would pertain when seen collectively and, much more often than not, on an individual trial basis as well. Finally, the inability to thoroughly assess the internal validity of each of the included trials, precluded an unequivocal appreciation of the collective and most of the individual trial estimates of the value of LTRAs as compared to ICs. At this time, it may be concluded that the collective evidence for the two LTRAs efficacy and safety has yet to be answered in a satisfactory fashion. This has precluded determining their exact clinical value as monotherapy, let alone as an adjunct to moderate or high doses of ICs as was recently recommended. Finally, likely the only other certainty highlighted by this review is the need to institute mechanisms by which to ensure the full and timely public disclosure of pertinent trial information and results to permit their evaluation by the public from whom the original trial participants were drawn, practitioners and any third parties charged with estimating the weight of all of the evidence concerning the value of any, especially emerging, health technology.

Authors' methods: Systematic review

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