ASCO 2024: MUC1 Vaccine Plus Neoadjuvant Chemotherapy for Early-Stage Breast Cancer

By: Julia Cipriano, MS
Posted: Friday, June 14, 2024

The frequently overexpressed MUC1 glycoprotein has been found to play a role in oncogenesis and resistance to breast cancer therapy. Christian F. Singer, MD, MPH, of the Medical University of Vienna, and colleagues thus conducted the multicenter phase II ABCSG 34 trial to evaluate the addition of the MUC1-based vaccine tecemotide (liposomal BLP25) to standard neoadjuvant systemic therapy in the HER2-negative early disease setting. Their findings, which were presented during the 2024 American Society of Clinical Oncology (ASCO) Annual Meeting (Abstract 587), revealed improvements in distant recurrence–free and overall survival with this investigational combination, although additional studies are warranted.

A total of 400 patients were randomly assigned in a 1:1 ratio to receive preoperative standard-of-care treatment ( [luminal A]: letrozole; premenopausal [all] or postmenopausal [triple-negative, luminal B]: epirubicin plus cyclophosphamide and docetaxel) with or without tecemotide. Long-term outcome data were available for 291 patients, of whom 236 were administered standard-of-care chemotherapy.

Among these patients with evaluable residual disease burden, there did not appear to be a significant increase in residual cancer burden 0 or 1 with vs without tecemotide (36.4% vs 31.5%; P = .42; chemotherapy: 40.5% vs 34.8%; P = .37). However, with a follow-up of 7 years, 80.8% of the patients who received tecemotide were alive and free from metastasis, compared with 64.7% of those who were not inoculated (hazard ratio [HR] for distant recurrence–free survival: 0.53; P = .005); 83.0% vs 68.2% were still alive (HR for overall survival = 0.53; P = .008). Those treated with tecemotide plus chemotherapy “had a particularly good outcome,” according to the study authors, with a distant recurrence–free survival rate of 81.9% (vs 65.0%; HR = 0.50; P = .007) and an overall survival rate of 83.6% (vs 67.8%; HR = 0.51; P = .016).

Disclosure: For full disclosures of the study authors, visit coi.asco.org.

2024 ASCO Annual Meeting

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