Persistence with denosumab and persistence with oral bisphosphonates for the treatment of postmenopausal osteoporosis: a retrospective, observational study, and a meta-analysis

The Summary The objectives of this study were to estimate persistence with denosumab and put these results in context by conducting a review of persistence with oral bisphosphonates. Persistence with denosumab was found to be higher than with oral bosphosphonates. Purpose This study had two objectives: to analyse persistence in Swedish women initiating denosumab for treatment of postmenopausal osteoporosis (PMO) and to put these findings in context by conducting a literature review and meta-analysis of persistence data for oral bisphosphonates. Methods The study used the Swedish Prescribed Drug Register and included women aged at least 50 years initiating denosumab between May 2010 and July 2012. One injection of denosumab was defined as 6-month persistence. Women were considered persistent for another 6 months if they filled their next prescription within 6 months + 56 days and survival analysis applied to the data. A literature search was conducted in PubMed to identify retrospective studies of persistence with oral bisphosphonates and pooled persistence estimates were calculated using a random-effects model. Results The study identified 2,315 women who were incident denosumab users. Mean age was 74 years and 61 % had been previously treated for PMO. At 12 and 24 months, persistence with denosumab was 83 % (95 % CI, 81-84 %) and 62 % (95 % CI, 60-65 %), respectively. The literature search identified 40 articles for inclusion in the meta-analysis. At 12 and 24 months, persistence with oral bisphosphonates ranged from 10 % to 78 % and from 16 % to 46 %, with pooled estimates of 45 % and 30 %, respectively. Conclusion These data from the Swedish Prescribed Drug Register and literature review suggest that persistence was higher with denosumab than with oral bisphosphonates.