NEW YORK, May 26, 2023 (GLOBE NEWSWIRE) — Y-mAbs Therapeutics, Inc. (the “Company” or “Y-mAbs”) (Nasdaq: YMAB) a commercial-stage biopharmaceutical company focused on the development and commercialization of novel, antibody-based therapeutic products for the treatment of cancer, today announced that a poster presentation featuring interim clinical data on naxitamab, a recombinant, humanized anti-GD2 monoclonal antibody, in combination with granulocyte-macrophage colony-stimulating factor (“GM-CSF”) will be presented at the American Society of Clinical Oncology (“ASCO”) Annual Meeting to be held June 2-6, 2023, in Chicago, Illinois.
Patients with high-risk neuroblastoma (“HR-NB”) commonly develop metastases in the bone and/or bone marrow. Approximately 15% of HR-NB patients are refractory to induction therapy and approximately 50% will relapse. The ongoing Phase 2 Trial 201 (NCT03363373) evaluates naxitamab in combination with granulocyte-macrophage colony-stimulating factor (“GM-CSF”) in patients with relapsed or refractory HR-NB with residual disease limited to bone and/or bone marrow. Patients with disease in soft tissues or actively progressing disease were excluded from the trial.
Curie Score (“CS”) is a semi-quantitative scoring system used to assess the extent of bone metastases and treatment response. Higher CS indicates more extensive bone involvement and may suggest a poorer prognosis.
An interim analysis of Trial 201 (data cutoff December 31, 2021) included 52 patients in the efficacy group and 74 patients in the safety group. The efficacy analyses included the overall response rate (ORR; complete response or partial response) and the reduction in CS by baseline disease status, i.e., refractory or relapsed disease. Clinically meaningful ORRs and reductions in CS were seen in patients regardless of baseline disease status. The ORR was 58% in patients with refractory disease and 42% in patients with relapsed disease. Furthermore, from a mean baseline CS of 5.5 and 5.7 in the refractory and relapsed subgroups (range 1-20 across the two subgroups), the mean change to end of naxitamab treatment was -4.2 and -1.2, respectively. Maximum reductions in CS for relapsed and refractory subgroups were -17 and -18, respectively. Overall, the most common naxitamab related serious adverse events were hypotension, pain, urticaria, and bronchospasm. Baseline CS did not affect the safety profile of naxitamab. Patients with refractory disease had a lower frequency of serious naxitamab related adverse events compared to patients with relapsed disease.
Naxitamab was licensed by the Company from Memorial Sloan Kettering (“MSK”). MSK has institutional financial interests in the compound.