Abstract
Objective:
To evaluate the cost-effectiveness of pregabalin in the treatment of fibromyalgia in a US patient population.
Methods:
A decision-analytic model was developed comparing pregabalin 150 mg twice a day (BID) and pregabalin 225 mg BID to placebo, duloxetine, gabapentin, tramadol, milnacipran, and amitriptyline in patients with severe fibromyalgia (Fibromyalgia Impact Questionnaire score >59; pain score >6.5). The model estimated response rates for all treatments at 12 weeks based on three randomized trials with pregabalin and a systematic review of published randomized controlled trials. Response was categorized as ≥30% improvement in baseline pain score plus global impression of change rating of much improved or very much improved. After 12 weeks of treatment, responders to treatment entered a treatment Markov model in which response was maintained, lost, or treatment discontinued. The cost-effectiveness end-points were cost per responder at 12 weeks and 1 year. Resource use was estimated from published studies and costs were estimated from the societal perspective.
Results:
Over 12 weeks, total cost per patient was $229 higher with pregabalin 150 mg BID than placebo, whereas pregabalin 225 mg BID was $866 less costly than placebo. At 1 year, pregabalin was cost saving and more effective than placebo, duloxetine, tramadol, milnacipran, and gabapentin. Compared with amitriptyline, pregabalin was not cost-effective at both dosages, although when excluding old and methodologically weak studies of clinical effectiveness of amitriptyline, pregabalin 225 mg BID became cost saving and pregabalin 150 mg BID was cost-effective.
Limitations:
Comparisons between pregabalin and other active agents are based on indirect comparisons, not head-to-head trials, and so should be interpreted with caution. Limitations for comparators include an inability to access sub-group data, inconsistency of response definitions, inclusion of older trials, and absence of long-term studies.
Conclusions:
This model found pregabalin to be cost-effective in treating patients with severe fibromyalgia.
Transparency
Declaration of funding
This study was funded by Pfizer Inc. Editorial support for development of this manuscript was provided by UBC Scientific Solutions and was funded by Pfizer Inc.
Declaration of financial/other relationships
AC and GZ are full-time employees of Pfizer Inc. AL is a full-time employee of IMS and served as a paid consultant to Pfizer Inc during the conduct of this study and the development of this manuscript. EC and CB received a consultancy fee from Pfizer Inc for contributing to this work. CB serves as a consultant for Forest Pharmaceuticals, Eli Lilly and Company, and Pfizer Inc, and has received research funding from Pfizer Inc.
Acknowledgments
The authors would like to thank Zahava Gabriel for conducting the systematic literature review of fibromyalgia treatments; Steve Lister, Javier Rejas, Sophie Marbaix, Sally Thompson, and Christin Prutz for their review, comments, and suggestions on the model, and Robert Sanchez and Joanna Lui for their technical contributions to the study. Editorial support was provided by Diane Hoffman, PhD, of UBC Scientific Solutions and was funded by Pfizer Inc. JME peer reviewers may have received honoraria for their review work. The peer reviewers on this manuscript have disclosed that they have no relevant financial relationships.