Nab-paclitaxel (Abraxane®, Celgene), a nanometer-sized albumin-bound paclitaxel, was developed to reduce the toxicities associated with conventional taxanes and is approved for the second-line treatment of metastatic breast cancer (mBC). This prospective, multicenter, non-interventional study was designed to characterize the treatment patterns, safety, and activity of nab-paclitaxel in young and elderly mBC patients (pts) in routine clinical practice.
Safety and tolerability of nab-paclitaxel was defined as the primary study endpoint. Secondary endpoints were overall response rate (ORR) and assessment of real-life dosages. Pts with confirmed mBC who met the eligibility criteria were enrolled and prospectively observed for at least 6 treatment cycles or until disease progression or unacceptable toxicity.
Between 5/2012 and 1/2016, 203 pts (median age: 58 years, range 33-91; 34 (17%) ≥70) were included at 16 sites. 81 pts (40%) had ≥3 metastatic lesions, 35 (17%) were triple-negative, and 93 (46%) had grade 3 disease. 44 pts (22%) received nab-paclitaxel as first-line, 54 (26%) as second-line, and 103 (50%) as third- to seventh-line therapy. A total of 1036 treatment cycles (median: 5; range: 1-19) were administered. In a preplanned interim outcome analysis conducted in 132 pts, the ORR was 39%, consisting of 4 complete (CR; 3%) and 47 partial responses (PR;36%). In addition, 43 patients (33%) had stable disease for a clinical benefit rate (CBR) of 72%. In the elderly cohort, 10 pts (30%) had PR and 3 pts (10%) had SD for a CBR of 40%.Overall, Nab-paclitaxel was well tolerated, with most adverse drug reactions (ADRs) mild or moderate in severity. The most common ADRs were peripheral neuropathy, neutro- and leukopenia. ADRs leading to the discontinuation of nab-paclitaxel occurred in 18 pts (9%). No new safety signals were identified and no significant differences in the reason for treatment discontinuation between pts
In this real-life study safety and efficacy data are consistent with previous clinical trial data. Of note, nab-paclitaxel was active and also well tolerated in pts aged ≥70 years.
Clinical trial identification
Legal entity responsible for the study
Medical University of Vienna, Austria
G. Steger, E. Petru, F. Haslbauer, D. Egle, A. Galid, T. Sliwa, A. Lang, T. Kühr, A. Petzer, R. Ruckser, B. Mlineritsch, R. Greil, M. Seifert, C. Singer, J. Andel, W. Kwasny, C. Marth, P. Pichler, C. Tinchon, R. Bartsch: Celgene: Honoraria, advisory boards, and travel support