A systematic review and meta-analysis of nab-paclitaxel mono-chemotherapy for metastatic breast cancer

Background

Although various clinical trials and real-life studies have tried to explore the value of nab-paclitaxel mono-chemotherapy for metastatic breast cancer (MBC), the safety and efficacy of nab-paclitaxel remain unclear which need to be systematically evaluated.

Methods

Electronic searches for prospective clinical trials evaluating nab-paclitaxel monotherapy for MBC were performed. Requisite data were extracted, integrated and analysed from the included studies according to the different study designs using systematic review and meta-analysis. Meta-regression and subgroup analysis were further performed to explore the potential risk factors affecting each individual outcome of interest following nab-paclitaxel monotherapy.

Results

Twenty-two studies with 3287 MBC patients were included. A total of 1685 MBC patients received nab-paclitaxel as first-line therapy, 640 patients as further-line therapy, and 962 patients as mixed-line therapy. A total of 1966 MBC patients (60.40%) received nab-paclitaxel weekly, 1190 patients (36.56%) received nab-paclitaxel triweekly and 99 patients (3.04%) received nab-paclitaxel biweekly. The overall incidence rates of all-grade neutropenia, leukopenia, peripheral sensory neuropathy, and fatigue were 52% (95% CI, 38–66%, I² = 98.97%), 58% (95% CI, 43–73%, I² = 97.72%), 58% (95% CI, 48–68%, I² = 97.17%), and 49% (95% CI, 41–56%, I² = 94.39%), respectively. The overall response rate (ORR) was 40% (95% CI, 35–45%, I² = 98.97%), and the clinical benefit rate (CBR) was 66% (95% CI, 59–73%, I² = 98.97%) following nab-paclitaxel monotherapy. The median progression-free survival (PFS) was 7.64 months (95% CI, 6.89–8.40 months, I² = 92.3%), and the median overall survival (OS) was 24.51 months (95% CI, 21.25–27.78 months, I² = 92.7%). Treatment line, human epidermal growth factor receptor-2(Her-2)-negative status and dosage were found to be sources of heterogeneity among the included studies. According to the meta-regression and subgroup analysis, grade 3/4 neutropenia occurred less frequently in Her-2-negative patients than in the entire population (P = 0.046). Patients who received first-line nab-paclitaxel monotherapy showed a higher ORR (P = 0.006) and longer PFS (P = 0.045). Efficacy outcomes were not affected by the administration schedule. However, within the same schedule, patients appeared to have a superior ORR (P = 0.044) and longer PFS (P = 0.03) with an increasing dosage of nab-paclitaxel administered.

Conclusions

The benefits brought by nab-paclitaxel mono-chemotherapy in the treatment of MBC are considerable while the harm is generally manageable. Further study and validation are needed to figure out the roles which the dosage, schedule and other factors play actually in nab-paclitaxel chemotherapy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08441-z.

Weekly nab-Paclitaxel in Metastatic Breast Cancer - Summary and Results of an Expert Panel Discussion

Taxanes are regarded as the most effective single agents in the treatment of metastatic breast cancer (MBC). For conventional taxanes, crucial toxicities and impairments in clinical efficacy are related to solvents necessary because of the agents' hydrophobicity. The mandatory premedication with corticosteroids causes additional side effects. Nab-paclitaxel is a solvent-free colloidal suspension of paclitaxel and human serum albumin that exploits the physiological transport properties of albumin. It is registered as monotherapy with a recommended dose of 260 mg/m(2) every 3 weeks for the treatment of patients with MBC, who have failed a first-line treatment of metastatic disease and for whom a standard anthracycline treatment is not indicated. Clinical evidence is available for the registered 3-weekly administration and for alternative weekly schedules in first and further lines of therapy of patients with MBC. During an advisory board meeting, a group of 8 German breast cancer experts reviewed the clinical data of nab-paclitaxel in MBC and discussed how nab-paclitaxel could be used in clinical practice on the basis of the current data.