P1-10-03: Colony Stimulating Factor Use with Taxane-Based Therapy for Metastatic Breast Cancer: Claims Analysis of Prophylaxis, Treatment, and Costs.

Abstract

Background: The taxanes (paclitaxel, docetaxel, and albumin-bound paclitaxel) are used in women with metastatic breast cancer (MBC). Clinical trials indicate that these drugs may differ in their toxicity profiles, including rates of neutropenia and need for colony stimulating factor (CSF) supportive therapy. Utilizing medical claims data, we evaluated prophylactic and treatment-related CSF use among women receive taxane-based chemotherapy regimens. Objective: To determine if differences exist in rates of CSF use for prophylaxis, treatment and associated costs in women receiving taxane-based chemotherapy for MBC. Methods: Women with MBC were identified with ICD-9-CM codes and by their prior use of adjuvant chemo regimens. Paid medical claims (source: Ingenix Consulting) from May 1, 2006 to April 30, 2009 were analyzed. Study groups were defined according to the first taxane administered. CSF utilization was classified as prophylaxis (0-5 days post-taxane administration), treatment (6-21 days post-taxane,) or non-taxane associated use (>21 days post-taxane). Comparisons were made between the taxane groups. All CSF costs were captured from date of first taxane to end of taxane therapy +21 days and categorized as above. Patients censored if ≥35 days elapsed with no taxane therapy. Two-stage regression analyses were performed. Control variables included age, Romano comorbidity score, and use of prior and other concurrent chemotherapy. Results: 4,503 women (mean age: 53 +/− 10 years) with MBC were identified: 2,599 in the docetaxel group; 1,643 received paclitaxel; and 261 received nab-paclitaxel. More patients receiving docetaxel received any CSF (75.6%) than either paclitaxel (49.8%) or albumin-bound paclitaxel (36.8% P<0.05 for each comparison). For docetaxel 70.5% of women received prophylactic CSF, whereas the rates were 47.0% for paclitaxel and 33.0 for albumin-bound paclitaxel (P<0.05). The rate of women receiving CSF in the albumin-bound paclitaxel group was not different than the other groups. Daily per-patient CSF expenditures during taxane therapy were $176.81 (95% CI, $168.20-$185.52) for docetaxel, $127.71(95% CI, $113.62-$142.60) for paclitaxel, and 46.24 (95% CI, $29.37-$67.25) for albumin-bound paclitaxel. Conclusions: Compared with docetaxel and paclitaxel, patients receiving albumin-bound paclitaxel had significantly lower prophylactic CSF use, yet did not experience any difference in treatment-related use. Daily per-patient CSF expenditures for albumin-bound paclitaxel were significantly lower than the other two taxanes. Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-10-03.