PACLITAXEL-BASED NANOPARTICLE DELIVERY SYSTEMS FOR BREAST CANCER: A SYSTEMATIC REVIEW AND META-ANALYSIS

ABSTRACT Breast cancer is most prevalent among women throughout the world and is a major cause of cancer related mortality. Systemic therapy is incomplete without paclitaxel, which on the one hand has weakly soluble forms (sb-PTX): low solubility limits its applications, and toxicity is not ideal. To overcome these limitations, nanoparticle albumin-bound paclitaxel (nab-PTX) was formulated as more soluble and improved drug delivery system and it eliminates the need for Cremophor EL, the solvent responsible for most hypersensitivity reactions. The comparative efficacy and safety of nab-PTX and sb-PTX is also clinically important, and to support creating an effective treatment regimen. Objective: To assess the efficacy and safety of nab-PTX versus sb-PTX in various breast cancer populations such as early-stage, HER2-positive breast cancer and breast cancer metastases. Data Sources: PubMed, Elsevier, Springer, Google Scholar, and Research Gate were systematically searched to retrieve English language articles and published from January 2010 to March 2025. Study Selection: Eligible studies were randomized controlled trials, prospective or retrospective cohort studies and systematic reviews with meta-analyses comparing nab-PTX with sb-PTX in breast cancer patients directly. Review articles, editorials, case reports and conference abstracts were excluded. Extract and Data synthesis :Data Study level data were screened and extracted by two independent reviewers Outcomes included pathological complete response (pCR), objective response rate (ORR) and adverse events. Pooled relative risks (RRs) and odds ratios (ORs) were computed using random effects models. This review was performed according to PRISMA 2020 guidelines. Main Outcomes and Measures: Primary outcomes: pCR and ORR. Secondary outcomes: Adverse events resulting during treatment such as hypersensitivity, neuropathy, hematological toxicity, gastrointestinal toxicity, alopecia, and fatigue. Results: Eight thousand five hundred forty three patients were included in 6 studies. Nab-PTX was more effective with pooled pCR standing at 48.7% compared with 38.2% as compared with sb-PTX (RR, 1.18 [95% CI, 1.081.29]; P <.001). Nab-PTX had an increased ORR (58.7% vs 45.2%; RR, 1.30 [95% CI, 1.07157]; P = .007). Lack of Cremophor EL significantly reduced hypersensitivity reaction with nab-PTX. Peripheral neuropathy had been more common, but was mild and reversible. Nab-PTX demonstrated similar or lower rates of toxicities compared to sb-PTX, particularly with related to hematological and gastrointestinal adverse events. Conclusions: Nab-PTX is linked to superior efficacy and better safety profile than sb-PTX in the treatment of breast cancer. These results support nab-PTX as an important therapeutic option especially in patients who are at risk of hypersensitivity reactions or in whom extensive neo adjuvant therapy is required. Long-term survival outcomes, cost-effectiveness and scalability remain areas for further research.