Efficacy and cost of nab-paclitaxel (nab-P) in metastatic melanoma (mM).

Abstract

e20033 Background: A recent phase III trial of nab-paclitaxel (nab-P, 130 nm albumin-bound paclitaxel) vs dacarbazine (DTIC) in mM demonstrated a significant improvement in progression-free survival (PFS). An economic analysis was applied to the results of this trial. Methods: Chemotherapy naive stage IV mM patients received nab-P 150 mg/m2 on days 1, 8, and 15 every 4 weeks or DTIC 1000 mg/m2 every 3 weeks. 529 patients were randomized to nab-P (n = 264) or DTIC (n = 265). The primary endpoint was independently assessed PFS, with overall survival (OS) as a secondary endpoint. Costs of nab-P and DTIC were taken from published 2013 Medicare reimbursement rates. A literature review identified costs for expected adverse events (AE), administration, and recently approved mM treatments. Results: In the intent-to-treat population, median PFS was 4.8 and 2.5 months in the nab-P and DTIC arms, respectively (HR: 0.792; P = 0.044). Median OS at the time of an interim analysis was 12.8 months with nab-P and 10.7 months with DTIC (HR: 0.831; P = 0.094; determination of ultimate statistical significance is pending full analysis at study conclusion). The most common grade ≥3 treatment-related AEs were neuropathy (nab-P: 25% vs DTIC: 0%) and neutropenia (nab-P: 20% vs DTIC: 10%). Grade 4 neutropenia rates were similar between arms (nab-P: 3% vs DTIC: 4%). Median time to neuropathy improvement by >1 grade was 28 days. Median treatment duration was 3 months with nab-P vs 2.1 months with DTIC. Incremental costs per patient were $23,359 ($24,663 for nab-P vs $1,304 for DTIC) including drug, infusion, and AE management costs. These costs compare favorably to incremental costs of over $50,000 for newly approved therapies with similar median OS gains vsDTIC. Conclusions: nab-P is the only chemotherapy in a phase III trial to demonstrate a significant and clinically meaningful delay in disease progression over dacarbazine. Total costs are attractive in the context of other agents recently approved for mM. Further analysis is merited when final OS is available. Clinical trial information: NCT00864253.