Multicenter randomized phase 2 trial of neoadjuvant TQB2102 in locally advanced or early HER2-positive breast cancer

TQB2102 is a bispecific HER2-directed antibody-drug conjugate. A multicenter randomized phase 2 trial in China evaluated neoadjuvant TQB2102 for HER2-positive breast cancer in patients with stage II and III disease. Patients were stratified by hormone receptor status and randomly assigned (1:1) to receive 6.0 mg/kg once every 3 weeks of TQB2102 for six (cohort 1) or eight cycles (cohort 2) or 7.5 mg/kg once every 3 weeks for six (cohort 3) or eight cycles (cohort 4). The primary endpoint was total pathologic complete response (tpCR) rate across all four cohorts (n=26 per cohort). When the lower limit of the 90% CI for tpCR rate exceeded 40%, efficacy was considered better than that of historical control. The tpCR rates were 57.7%, 76.9%, 61.5%, and 69.2% in the four cohorts, with lower limits of the 90% CI exceeding 40% in all cohorts. The incidence rates of grade ≥ 3 treatment-related adverse events were 23.1% for cohort 1, 30.8% for cohort 2, 30.8% for cohort 3, and 26.9% for cohort 4. No treatment-related deaths occurred. The authors conclude that neoadjuvant TQB2102 showed robust activity and was well-tolerated.