Comparison of the Efficacy, Safety, Pharmacokinetic and Immunogenicity of UJVIRA™ (ZRC-3256, Trastuzumab Emtansine) With the Kadcyla® (Trastuzumab Emtansine) in the Treatment of HER2-positive Metastatic Breast Cancer: A Randomized, Open-label, Multicenter Study in India

Abstract Background: UJVIRA is the first DCGI approved biosimilar of trastuzumab emtansine (Kadcyla) which may offer an alternative cost-effective treatment option for HER2-positive metastatic breast cancer patients in India. This article summarizes the available clinical evidence supporting the biosimilarity of UJVIRA and Kadcyla with respect to efficacy, pharmacokinetic, safety, and immunogenicity. Methods: A phase 3, randomized, open-label, active-controlled study was conducted at 31 sites across India. A total of 168 patients were enrolled and randomized to receive either UJVIRA or Kadcyla. Of which, only first 50 patients were included in pharmacokinetic assessment. UJVIRA or Kadcyla were administered at a dose of 3.6 mg/kg by intravenous infusion every 3 weeks (21 days) for 8 cycles or until disease progression or unmanageable toxicity, whichever was earlier. The study assessed efficacy (ORR), safety, pharmacokinetics, and immunogenicity. Results: The ORR at the end of Week 24 was 37.76% in the UJVIRA and 33.33% in the Kadcyla group. The risk difference was 4.42% [-12.01, 20.85]. It met non-inferiority margin of -15%. The pharmacokinetic parameters were comparable between groups. No anti-drug antibody was detected in any of the treatment groups. The overall safety profile in terms of TEAEs and laboratory abnormalities was also comparable between the treatment groups. Conclusion: Results demonstrated biosimilarity between UJVIRA and Kadcyla in terms of efficacy, safety, pharmacokinetics, and immunogenicity. Therefore, UJVIRA could prove to be a cost-effective treatment alternative for HER2-positive metastatic breast cancer patients in India.