title: Patterns of use for brand-name versus generic oral bisphosphonate drugs in Ontario over a 13-year period: a descriptive study.
abstract: BACKGROUND
  Bisphosphonates are the first-line therapy for the treatment of osteoporosis. In the province of Ontario, the Ontario Drug Benefit Program funds medications for patients aged 65 years and older. The Ontario Drug Benefit Program has a generic substitution policy that requires lower-cost generic drugs to be dispensed when they are available. However, there is controversy surrounding the efficacy and tolerability of generic bisphosphonates. The objective of this study was to describe patterns in the use of brand-name versus generic formulations when dispensing oral bisphosphonate over a 13-year period.
  
  
  METHODS
  We identified all osteoporotic preparations for alendronate and risedronate that were dispensed through the Ontario Drug Benefit Program from 2001 to 2014. We stratified our sample into community-dwelling residents and residents in long-term care facilities. The number of prescriptions dispensed per month were plotted to illustrate trends over time.
  
  
  RESULTS
  We found a rapid switch from brand-name to generic bisphosphonate equivalents immediately after the generic became available on the Ontario Drug Benefit formulary, with generics accounting for > 88% of dispensed drug within 2 months. We also observed a reduction in the number of generic drugs dispensed each time a new brand-name alternative (e.g., monthly risedronate, weekly alendronate plus vitamin D) was introduced to the formulary. The dispensing trends were similar in the community and long-term care settings.
  
  
  CONCLUSIONS
  The Ontario Drug Benefit Program generic substitution policy resulted in rapid uptake of generic oral bisphosphonates among seniors in Ontario. However, there was a switch away from generic medications to new brand-name alternatives whenever they were introduced to the formulary. Therefore, some patients continued to use brand-name bisphosphonate despite the availability of generic options.
authors.affiliation: Department of Medicine, University of Western Ontario, London, Ont.
authors.forename: Lisa-Ann
authors.initials: LA
authors.lastname: Fraser
authors.affiliation: Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ont.
authors.forename: Jordan M
authors.initials: JM
authors.lastname: Albaum
authors.affiliation: Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ont.
authors.forename: Mina
authors.initials: M
authors.lastname: Tadrous
authors.affiliation: Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ont.
authors.forename: Andrea M
authors.initials: AM
authors.lastname: Burden
authors.affiliation: Institute for Clinical and Evaluative Sciences (ICES), London, Ont.
authors.forename: Salimah Z
authors.initials: SZ
authors.lastname: Shariff
authors.affiliation: Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ont. ; Institute for Clinical and Evaluative Sciences (ICES), London, Ont.
authors.forename: Suzanne M
authors.initials: SM
authors.lastname: Cadarette
references.citation: CMAJ. 2010 Nov 23;182(17):1864-73
references.pmid: 20940232
references.citation: Osteoporos Int. 2009 Aug;20(8):1369-76
references.pmid: 19020921
references.citation: Ann Intern Med. 2014 Jul 15;161(2):96-103
references.pmid: 25023248
references.citation: Osteoporos Int. 2014 Apr;25(4):1225-35
references.pmid: 24287510
references.citation: Osteoporos Int. 2012 Apr;23(4):1475-80
references.pmid: 21901476
references.citation: Cochrane Database Syst Rev. 2006 Apr 19;(2):CD005979
references.pmid: 16625648
references.citation: JAMA. 1999 Oct 13;282(14 ):1344-52
references.pmid: 10527181
references.citation: Osteoporos Int. 2009 Oct;20(10):1735-47
references.pmid: 19266138
references.citation: JAMA Intern Med. 2013 Feb 11;173(3):202-8
references.pmid: 23277164
references.citation: Osteoporos Int. 2012 Aug;23(8):2201-9
references.pmid: 22120909
references.citation: Can J Clin Pharmacol. 2003 Summer;10(2):67-71
references.pmid: 12879144
references.citation: Arch Osteoporos. 2013;8:128
references.pmid: 23475734
references.citation: Rheumatol Int. 2009 Dec;30(2):213-21
references.pmid: 19430791
references.citation: Int J Clin Pharmacol Ther. 2005 Oct;43(10):472-9
references.pmid: 16240704
references.citation: Osteoporos Int. 2012 Jan;23(1):213-21
references.pmid: 21953472
references.citation: Lancet. 1996 Dec 7;348(9041):1535-41
references.pmid: 8950879