Cellectar Biosciences, Inc. (NASDAQ:CLRB), a late-stage clinical biopharmaceutical company focused on the discovery, development and commercialization of targeted drugs for the treatment of cancer, presented data
Cellectar Biosciences, Inc. (NASDAQ:CLRB), a late-stage clinical biopharmaceutical company focused on the discovery, development and commercialization of targeted drugs for the treatment of cancer, presented data from 11 multiple myeloma patients from the company's ongoing Phase 2 CLOVER-1 study of iopofosine I-131 in a poster at the American Society of Hematology (ASH) Annual Meeting and Exposition.
The multiple myeloma patients were at least triple class refractory (defined as refractory to an immunomodulatory agent, proteasome inhibitor and monoclonal antibody) with data current as of the end of May 2021. Patients had a median of greater than 7 prior therapies with 50% classified as high risk. Initial results in these patients showed an overall response rate (ORR) of 45.5%, a clinical benefit rate (CBR) of 72.7% and a disease control rate (DCR) of 100%. Median progression free survival (PFS) was 3.4 months. In a subset of 5 quad/penta drug refractory patients, efficacy increased, demonstrating an ORR of 80% and CBR of 100% in this highly treatment refractory group. The most commonly observed treatment emergent adverse events were cytopenias that included Grade 3 or 4 thrombocytopenia (62.5%), anemia (62.5%), neutropenia (62.5%) and decreased white blood cell count (50%). Treatment emergent adverse events were mostly limited to bone marrow suppression in line with prior observations. No patients experienced a treatment emergent adverse event of neuropathy, arrhythmia, cardiovascular event, bleeding, ocular toxicities, renal function, alterations in liver enzymes, or infusion-site reactions or adverse events.
"These results in heavily pre-treated, highly refractory patients are very encouraging, and show that iopofosine I-131 has the potential to be a meaningful part of the treatment regimen in multiple myeloma," said Dr. Sikander Ailawadhi, professor of medicine, Lead, International Cancer Center, Division of Hematology/Oncology, Departments of Medicine and Cancer Biology at Mayo Clinic Jacksonville, Florida and principal investigator of the Phase 2 CLOVER-1 study.
James Caruso, president and CEO of Cellectar, said, "Unfortunately, there remains a need for additional therapies and treatment options for patients with refractory multiple myeloma. We believe iopofosine I-131's demonstrated ability to specifically target cancer cells potentially represents an important advancement in cancer-targeting treatments. We look forward to sharing additional data as the Phase 2 CLOVER-1 study matures. In parallel, we continue to execute on our ongoing pivotal study in Waldenstrom's macroglobulinemia where we anticipate announcing results of a futility analysis in the first quarter of 2022."
Patients in the study received up to 4, approximately 20 minute IV infusions of iopofosine I-131 over 3 months, with doses given 14 days apart in each cycle and a maximum of 2 cycles. Low dose dexamethasone 40mg weekly (20mg in patients ≥ 75), was provided for up to 12 weeks. Following treatment with iopofosine I-131, approximately 91% of patients experience a reduction in tumor marker with approximately 73% experiencing greater than 37% reduction.
A copy of the poster will be available after the presentation on the Posters and Presentations section of the company's website.