title: Reductions in Use of Colchicine after FDA Enforcement of Market Exclusivity in a Commercially Insured Population.
abstract: BACKGROUND
  A brand-name version of colchicine (Colcrys) was introduced after its manufacturer conducted a clinical trial in acute gout patients, leading to higher prices for this drug.
  
  
  OBJECTIVE
  We analyzed the impact of the new single-source colchicine product on prescribing and patient health spending as well as incidence rates of potentially dangerous concomitant use of clarithromycin and cyclosporine after formal FDA approval.
  
  
  METHODS
  We conducted a retrospective cohort study of UnitedHealth-affiliated enrollees newly diagnosed with gout or FMF.
  
  
  METHODS
  Among gout and FMF patients separately, we assessed linear trends in colchicine prescriptions, prescription drug costs, and total health care costs from 2009 to September 2010 (market exclusivity announced) compared to January 2011 (market exclusivity enforced) through 2012. Next, we estimated trends in co-prescription within 15 days of clarithromycin, azithromycin (indicated on the Colcrys label for use in place of clarithromycin), and cyclosporine.
  
  
  RESULTS
  Among gout patients, before Colcrys' market exclusivity, the odds of receiving colchicine within 30 days of gout diagnosis increased 1.4 %/month (OR: 1.014, 95 % CI: 1.011-1.018). Following FDA action, the odds decreased by 0.5 %/month (OR: 0.995, 95 % CI: 0.992-0.999) (p < 0.001). Similarly, among FMF patients, odds of initiating colchicine changed from an increase of 2.8 %/month to a decrease by 7.6 %/month (p = 0.01). Patients receiving colchicine experienced increases in average monthly prescription drug costs ($418 vs. $651, p < 0.001) and health care costs ($3,406 vs. $3,534, p < 0.001). Incidence rates of colchicine/clarithromycin co-prescription before and after FDA action did not change, while co-prescription of colchicine/cyclosporine increased after introduction of Colcrys [-0.75 monthly change in patients (95 % CI: -1.07, -0.43) vs. 0.13 (95 % CI: -0.16, 0.42), p < 0.001].
  
  
  CONCLUSIONS
  The FDA's actions were associated with a reduction in colchicine initiation and an increase in patient spending. By contrast, we did not observe any association with improvements in avoidance of potentially dangerous co-prescriptions.
authors: Program On Regulation, Therapeutics, And Law (PORTAL), Division of Pharmacoepidemiology and Pharmacoeconomics, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA. akesselheim@partners.org.|Harvard Medical School, Boston, MA, USA. akesselheim@partners.org.
authors: Aaron S
authors: AS
authors: Kesselheim
authors: Program On Regulation, Therapeutics, And Law (PORTAL), Division of Pharmacoepidemiology and Pharmacoeconomics, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA.|Harvard Medical School, Boston, MA, USA.
authors: Jessica M
authors: JM
authors: Franklin
authors: Program On Regulation, Therapeutics, And Law (PORTAL), Division of Pharmacoepidemiology and Pharmacoeconomics, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA.|Division of Rheumatology, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA.|Harvard Medical School, Boston, MA, USA.
authors: Seoyoung C
authors: SC
authors: Kim
authors: Program On Regulation, Therapeutics, And Law (PORTAL), Division of Pharmacoepidemiology and Pharmacoeconomics, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA.|Harvard Medical School, Boston, MA, USA.
authors: John D
authors: JD
authors: Seeger
authors: Program On Regulation, Therapeutics, And Law (PORTAL), Division of Pharmacoepidemiology and Pharmacoeconomics, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA.|Division of Rheumatology, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA.|Harvard Medical School, Boston, MA, USA.
authors: Daniel H
authors: DH
authors: Solomon
mesh_terms: D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D017291:Clarithromycin / Q000627:therapeutic use; D003078:Colchicine / Q000191:economics / Q000627:therapeutic use*; D017277:Drug Approval; D016527:Drug Costs / Q000706:statistics & numerical data / Q000639:trends; D004347:Drug Interactions; D011307:Drug Prescriptions / Q000706:statistics & numerical data; D004363:Drug Utilization / Q000706:statistics & numerical data / Q000639:trends*; D004465:Economic Competition; D010505:Familial Mediterranean Fever / Q000188:drug therapy; D005260:Female; D006073:Gout / Q000188:drug therapy* / Q000191:economics; D006074:Gout Suppressants / Q000191:economics / Q000627:therapeutic use*; D017048:Health Care Costs / Q000706:statistics & numerical data / Q000639:trends; D006801:Humans; D007348:Insurance, Health; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D014481:United States; D014486:United States Food and Drug Administration
chemical_list: D000900:Anti-Bacterial Agents; D006074:Gout Suppressants; D017291:Clarithromycin; D003078:Colchicine