%0 Journal Article %T A single-arm, multicenter, phase 2 clinical study of recombinant humanized anti-HER2 monoclonal antibody-MMAE conjugate (MRG002) in HER2-positive unresectable locally advanced or metastatic urothelial carcinoma. %A Qu W %A Fu C %A Han W %A Luo H %A Quan J %A Chen L %A Liao Y %A Hu C %A Hu H %A Niu Y %A Xu D %A Chen M %A Chen J %A Liu Y %A Chen G %A Luo Z %A Shi B %A Sun Y %A Zhou F %A Zhou A %J Eur J Cancer %V 205 %N 0 %D 2024 Jul 10 %M 38772302 %F 10.002 %R 10.1016/j.ejca.2024.114096 %X BACKGROUND: MRG002 is a novel HER2-targeted antibody-drug conjugate being investigated in the MRG002-006 trial to evaluate the efficacy and safety in HER2-positive urothelial carcinoma patients.
METHODS: This is an open-label, single-arm, multicenter phase II study. Eligibility criteria included: histologically confirmed HER2 IHC 2 + or 3 + UC, prior received ≥ 1 standard treatment. Patients in this study received MRG002 every 3 weeks until progressive disease or unacceptable toxicity. The primary endpoint was confirmed ORR per RECIST 1.1.
RESULTS: As of February 24, 2023, a total of 43 patients were enrolled. The median age was 60. 9 patients were dosed at 2.6 mg/kg and 34 patients were dosed at 2.2 mg/kg. At baseline, most patients (29/43) received ≥ 2 lines of treatment and 35 (81.4%) patients had prior ICI therapy. FISH test was performed in 41 patients and 9 (22.0%) were positive. By the cut-off date, 41 patients were evaluable and the ORR was 53% (95%CI:38.9%-67.5%), with 6.9% CR, and the DCR was 83.7% (95%CI:70.0%-91.9%). The median PFS and OS for the 43 patients were 7.0 months (95%CI:5.4-NE) and 14.9 months (95%CI:11.9-NE), respectively. The ORR was 77.8% in 9 patients with positive HER2 FISH results. Most common treatment-related AEs were anemia (51.2%), alopecia (44.2%) and neutropenia (39.5%); most were grade 1 or 2.
CONCLUSIONS: Preliminary results of MRG002 demonstrated a clinically meaningful response in pretreated HER-2 positive unresectable locally advanced or metastatic UC patients. MRG002 at 2.2 mg/kg was well tolerated with a manageable toxicity.