Economic value of romiplostim for management of chemotherapy-induced thrombocytopenia in gastrointestinal cancers in the United States.

Abstract

e23153 Background: Chemotherapy-induced thrombocytopenia (CIT) is a common complication of multiagent chemotherapy that may lead to dose reductions, treatment delays, or discontinuation, potentially compromising cancer outcomes and increasing healthcare utilization. In the phase 3 RECITE trial, romiplostim improved platelet counts and reduced CIT-related chemotherapy modifications in patients with gastrointestinal (GI) cancers. We evaluated the cost-effectiveness of romiplostim versus usual care in GI cancer patients receiving chemotherapy in the US. Methods: A Markov model with time-dependent transitions was developed from the US health system perspective. A hypothetical cohort of adults with GI cancers and baseline thrombocytopenia receiving oxaliplatin-based chemotherapy received romiplostim plus usual care or usual care alone. Patients transitioned among five health states: full-dose chemotherapy, modified chemotherapy, major bleeding, disease progression, and death. The model included a 6-month chemotherapy phase followed by a post-chemotherapy phase, using 3-week cycles and 1- and 5-year horizons. Romiplostim (2 mcg/kg) was initiated after two chemotherapy cycles upon development of CIT and administered weekly during chemotherapy. Transition probabilities, costs, and utilities were derived from published literature and clinical trial data. Outcomes included total costs, quality-adjusted life years (QALYs), incremental cost-effectiveness ratios (ICERs), chemotherapy modifications avoided, and major bleeding events avoided. Cost-effectiveness was assessed against US willingness-to-pay thresholds of $100,000 and $150,000 per QALY gained. One-way sensitivity analyses evaluated parameter uncertainty. Results: Over a 5-year horizon, romiplostim was associated with a gain of 0.4 QALYs (≈ 5 months) and increased costs by $32,079 versus usual care, resulting in an ICER of $77,591 per QALY gained which indicated romiplostim cost-effectiveness at the prespecified thresholds. Over a 1-year horizon, the ICER was $482,090 per QALY gained, suggesting romiplostim was not cost-effective in the short term. Romiplostim reduced chemotherapy modifications at a cost of $64,179 per modification avoided. During chemotherapy, major bleeding events were reduced by about 15 events per 100 patients, corresponding to $213,460 per bleeding episode avoided. Results were most sensitive to time horizon, romiplostim dose and price, vial size/drug-wastage, chemotherapy duration, and transition probabilities. Conclusions: In patients with GI cancers who develop CIT, romiplostim may provide long-term economic value by preserving chemotherapy delivery, reducing bleeding complications, and improving quality-adjusted survival. These findings support the targeted use of romiplostim as a value-based supportive care strategy in oncology.