Cost-Effectiveness of Durvalumab Following Chemoradiotherapy in Unresectable Stage III NSCLC Patients in the US: An Update Based on 4-Year Survival Data
Author(s)
Seal B1, Mooradian MJ2, Van Keep M3, Dunlop W4, Brannman L1, Yong C5
1AstraZeneca Pharmaceuticals LP, Gaithersburg, MD, USA, 2Massachusetts General Hospital, Harvard University, Boston, MA, USA, 3BresMed Netherlands, Utrecht, UT, Netherlands, 4AstraZeneca Pharmaceuticals, Cambridge, UK, 5AstraZeneca Pharmaceuticals, LP, Rockville, MD, USA
OBJECTIVES: Assess the effects of using 4-year time-to-event data from the PACIFIC trial in estimating the cost-effectiveness of durvalumab following chemoradiotherapy (CRT) versus CRT alone in patients with unresectable stage III NSCLC. METHODS: Updated PACIFIC trial results, incorporating additional follow-up, were recently published. Four-year progression-free survival (PFS), time to progression (TTP), post-progression survival (PPS) and overall survival (OS) data from the update were added to a 3-state (progression-free, progressed, and death) state-transition (semi-Markov) model that was based on PACIFIC 3-year OS and PPS data and 2-year PFS and TTP data. Other model inputs, such as costs and utilities, remained constant for consistency when comparing outcomes. Modelling was conducted from the Medicare payer perspective over a 30-year time horizon, which was considered lifelong. RESULTS: The 4-year time-to-event data for the durvalumab and placebo arms in PACIFIC closely matched the original model’s extrapolated OS and PFS. For the durvalumab arm, there was a 1% difference between actual 4-year OS and PFS and values predicted using 3-year PPS and 2-year TTP and PFS data. For the placebo arm there was a difference of 5% in OS and 6% in PFS between estimates from the previous model and actual 4-year data. Durvalumab following CRT was associated with incremental quality-adjusted life year (QALY) gains of 1.65 and 1.49 QALYs in the original and updated models respectively. The original and updated ICERs for a Medicare-aged population were $55,285 and $60,692 per QALY respectively, both below a $100,000 willingness-to-pay threshold. CONCLUSIONS: The model was highly accurate at predicting 4-year OS and PFS in the durvalumab arm. Updated ICER estimates based on 4-year time-to-event data from PACIFIC indicate that durvalumab remains a cost-effective treatment option for patients with unresectable stage III NSCLC following chemoradiotherapy.
Conference/Value in Health Info
2021-05, ISPOR 2021, Montreal, Canada
Value in Health, Volume 24, Issue 5, S1 (May 2021)
Code
PCN44
Topic
Economic Evaluation
Topic Subcategory
Cost-comparison, Effectiveness, Utility, Benefit Analysis
Disease
Biologics and Biosimilars, Drugs, Oncology