Nab-Paclitaxel weekly or every 3 weeks compared to standard docetaxel as first-line therapy in patients with metastatic breast cancer: An economic analysis of a prospective randomized trial

Docetaxel is an effective therapy for metastatic breast cancer (MBC) and considered a first-line standard of care in many jurisdictions. However, it may be associated with dose-limiting toxicity often requiring dose reductions, delays and in some cases prophylactic hematopoietic growth factors. A nanoparticle albumin-bound (nab) formulation of paclitaxel was developed to overcome the safety drawbacks of solvent-based taxanes and to improve efficacy. A randomized phase II trial comparing nab-paclitaxel 100 or 150 mg/m² weekly 3 out of 4 weeks and nab-paclitaxel 300 mg/m² every-3-week (q3w) to docetaxel 100 mg/m² q3w reported improved progression-free survival (PFS) and reduced toxicity with the former regimens. From resource use captured during the trial, an economic analysis from the perspective of the United Kingdom (UK) National Health Service was conducted. Resource use data contained within the trial database were converted to UK costs. These consisted of costs for chemotherapy, drug delivery, monitoring, supportive care drugs and hospitalization due to toxicity. Univariate and multivariate regression analyses were then conducted to compare the total cost of therapy in patients randomized to each of the four regimens. Growth factor use, hospitalization due to side effects and toxicity-induced protocol discontinuations were higher in the docetaxel group. When all of the cost components were combined for the entire population (N = 300), patients in the nab-paclitaxel 100 mg/m² weekly and 300 mg/m² q3w groups had comparable average costs to the docetaxel arm (£15,396 vs. £15,809 vs. £12,923; P = NS). The nab-paclitaxel 150 mg/m² weekly arm had significantly higher overall costs of £27,222 per patient but had a significant improvement in PFS compared to docetaxel. Relative to docetaxel, the incremental costs per progression-free year gained with nab-paclitaxel 100, 150 mg/m² weekly and 300 mg/m² q3w were £5,600, £31,800 and £9,900, respectively. Given its improved safety profile, potentially enhanced efficacy and comparable economic impact, nab-paclitaxel (weekly or q3w) can be considered a reasonable alternative to docetaxel as first-line chemotherapy for MBC.