Y-mAbs Announces Naxitamab Chemoimmunotherapy Investigational Trial for High-Risk Neuroblastoma Meets Primary Endpoint

Rhea-AI Summary

Y-mAbs Therapeutics announced that Dr. Shakeel Modak will present results from a trial of naxitamab-based chemoimmunotherapy for high-risk neuroblastoma at the ASCO Annual Meeting from June 3-7, 2022. The trial focused on patients with chemoresistant disease, showing a 30.6% objective response rate in the MSK phase 2 trial, with significant responses in heavily pre-treated patients. The treatment showed manageable toxicity, with no unexpected severe side effects. Y-mAbs is advancing its antibody-based therapeutics in cancer treatment.

Positive

• Primary endpoint met: 30.6% objective response rate in the MSK trial.
• High ORR of 64% observed in patients at MSK, indicating effectiveness.
• Naxitamab showed a complete response in 57% of patients with bone marrow involvement.

Negative

• Treatment remains investigational and not approved by health authorities.
• Toxicities included myelosuppression and diarrhea, potentially concerning for patients.

NEW YORK, May 26, 2022 (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 Dr. Shakeel Modak, MD from Memorial Sloan Kettering (“MSK”) will present results from the naxitamab-based chemoimmunotherapy trial in patients with chemoresistant high-risk neuroblastoma (“HR-NB”), at the American Society of Clinical Oncology (“ASCO”) Annual Meeting to be held June 3-7, 2022.

This clinical trial studied the combination of Humanized anti-GD2 antibody naxitamab, Irinotecan, Temozolomide and Sargramostim (GM-CSF), (“HITS”) protocol, and included cohort of patients that were treated at MSK in a phase 2 protocol, and at Hospital Sant Joan de Déu (“HJSD”) per protocol on compassionate use basis. Health authorities have not established the safety and efficacy of the HITS protocol, as it is investigational and has not been approved by health authorities.

Eligibility criteria included evaluable or measurable chemoresistant disease. Prior anti-GD2 or irinotecan/temozolomide therapy was permitted. Each cycle, administered 3-5 weeks apart, comprised irinotecan, temozolomide, naxitamab and GM-CSF. The primary endpoint of the phase 2 trial at MSK was complete response (“CR”) and partial response (“PR”) after 4 cycles.

Of 90 previously heavily treated patients, (38 at MSK in the phase 2 trial, and 52 at HJSD), eight had HR-NB refractory to induction chemotherapy and 82 had up to six prior relapses.

The primary endpoint was reached in the MSK phase 2 trial: Objective Response Rate (“ORR”) according to the International Neuroblastoma Response Criteria (“INRC”) of 30.6 %, with a lower boundary of 20.4%. In the entire cohort, responses were 26% for CR, 11% for PR, 9% for mixed response, 27% for stable disease and 27% for progressing disease (“PD”). In the MSK phase 2 trial, the ORR was 64% for all patients, with soft tissue (48%) and skeletal MIBG uptake (66%). CR in bone marrow was seen in 57% of the patients. The ORR in patients with MYCN-amplification was 25%, in patients with refractory disease 100%, and in patients with relapsed disease 61%. Moreover, in patients who had previously received irinotecan/temozolomide or naxitamab, the ORR was 64% and 68%, respectively. In patients who had previously received dinutuximab/irinotecan/temozolomide, the ORR was 42% (five out of 12 patients).

Toxicities included myelosuppression and diarrhea as expected with irinotecan/temozolomide, pain and hypertension as expected with naxitamab, plus febrile neutropenia. No other >grade 2 unexpected toxicities occurred, and the treatment was outpatient. In this trial, human anti-human antibody did not develop in any of the 50 patients providing samples for testing.

“We are very pleased to present data for the HITS protocol,” stated Thomas Gad, Founder, President and Interim CEO. “Responses in patients with relapsed or progressive high-risk neuroblastoma are challenging, as chemo-resistant disease is considered an obstacle, so we are excited to see this study met its primary endpoint. This further demonstrates the potential role for DANYELZA in HR-NB. No other GD2 antibody has been studied in such a heavily pre-treated patient population.”

Researchers at Memorial Sloan Kettering Cancer Center MSK developed naxitamab, which is exclusively licensed by MSK to Y-mAbs. As a result of this licensing arrangement, MSK has institutional financial interests in the compound.

About Y-mAbs

Y-mAbs is a commercial-stage biopharmaceutical company focused on the development and commercialization of novel, antibody-based therapeutic cancer products. In addition to conventional antibodies, the Company’s technologies include bispecific antibodies generated using the Y-BiClone platform and the SADA platform. The Company’s broad and advanced product pipeline includes one FDA-approved product, DANYELZA® (naxitamab-gqgk), which targets tumors that express GD2, and one product candidate at the registration-stage, OMBLASTYS® (omburtamab), which targets tumors that express B7-H3.

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DANYELZA®, OMBLASTYS® and Y-mAbs® are registered trademarks of Y-mAbs Therapeutics, Inc.

Contact:

Y-mAbs Therapeutics, Inc.
230 Park Avenue, Suite 3350
New York, NY 10169
USA

+1 646 885 8505

E-mail: info@ymabs.com

FAQ

What are the results of the naxitamab trial presented by Y-mAbs at ASCO 2022?

The trial showed a 30.6% objective response rate, with notable efficacy in heavily pre-treated patients with high-risk neuroblastoma.

When will the ASCO Annual Meeting take place for Y-mAbs?

The ASCO Annual Meeting will be held from June 3-7, 2022.

What is the patient cohort in the naxitamab trial conducted by Y-mAbs?

The trial included 90 patients with chemoresistant high-risk neuroblastoma, many of whom had multiple prior relapses.

What were the toxicity results from the naxitamab trial?

The trial reported manageable toxicities such as myelosuppression and diarrhea, with no unexpected severe toxicities noted.

What is Y-mAbs's primary product targeting neuroblastoma?

Y-mAbs's primary product is DANYELZA (naxitamab-gqgk), which targets tumors expressing GD2.