Utilization impacts of new oral substitutes for parenteral cancer-related therapies

Background: Iron chelation therapy (ICT) is indicated in myelodysplastic syndrome (MDS) patients with transfusion-related iron overload. Deferoxamine, administered by lengthy subcutaneous infusions 5 to 7 days per week, was FDA–approved in 1968, whereas the oral chelator deferasirox was approved in November 2005. Objective: To examine the impact of deferasirox market entry on ICT utilization. Study Design: Observational study of ICT use in a cohort selected from 100% of Medicare beneficiaries with MDS diagnostic codes from 2004 to 2008, enrolled in Medicare Part D, and eligible for ICT based on a history of receipt of 20 units of packed red blood cells. Methods: Cox proportional hazards regression models tested the effect of deferasirox market entry on ICT utilization. Adequacy of therapy dose and duration were compared for oral compared with infused ICT users. A post hoc analysis predicted impacts on ICTrelated spending. Results: Eligible beneficiaries (n = 3843) had a median age of 78 years. Individuals who became ICT eligible after deferasirox market entry were 80% more likely to receive ICT by end of 2008. Deferoxamine and deferasirox doses were adequate in fewer than 10% and about 73% of users, respectively. Treatment duration was longer for deferasirox compared with deferoxamine (median 47 weeks vs 17 weeks). Conclusion: Deferasirox market entry was associated with increased ICT use and more adequate treatment dose and duration. Calculated expenditures for a typical treatment course were $46,142 for deferasirox versus $2761 for deferoxamine, representing a substantial cost increase associated with ICT use.