- Trastuzumab biosimilar ABP 980 is as safe and effective as trastuzumab for early human epidermal growth factor receptor 2 (HER2)-positive breast cancer.
Why this matters
- Trastuzumab biosimilars have the potential to cut costs and expand access to care.
- Randomized, controlled, double-blind, multicenter, phase 3 clinical trial of ABP 980 (n=364) or trastuzumab (n=361).
- Trial had 3 phases: neoadjuvant therapy, surgery, and adjuvant therapy.
- Neoadjuvant therapy: 8 mg/kg of ABP 980 or trastuzumab in loading dose with paclitaxel, followed by 3 cycles of 6 mg/kg of ABP 980 or trastuzumab with paclitaxel every 3 weeks in 30 minute intravenous infusions;
- Surgery: 3-7 weeks after completion of neoadjuvant therapy;
- Adjuvant therapy: ABP 980 or trastuzumab every 3 weeks for up to 1 year.
- Funding: Amgen.
- Pathologic complete response (pCR) attained (in local laboratory review) by 48% of ABP 980 group and 41% of trastuzumab group, with risk difference of 7.3% (90% CI, 1.2-13.4) and risk ratio (RR) of 1.188 (90% CI, 1.033-1.366), indicating noninferiority of lower boundaries of 90% CIs for risk difference and RR, and upper boundaries exceeding predefined equivalence margins of 13% and 1.318, respectively.
- No difference in grade 3 or worse adverse events was seen.
- Locally reviewed pCR.