Cellectar Biosciences expects topline data from WM CLOVER-WaM trial in 2H23

Cellectar Biosciences provided an update for its iopofosine I 131 clinical program and guidance related to its Waldenstrom’s macroglobulinemia CLOVER-WaM pivotal trial, as well as preclinical advancements to its proprietary phospholipid ether drug conjugate platform. The company now expects to release top-line data from the WM CLOVER-WaM trial in the second half of 2023 and assuming NDA approval, remains on target for a 2024 product launch. Cellectar experienced delays with trial start-up activities, such as site contracting and country regulatory responses, which slowed the initial pace of site initiations resulting in lower-than-expected patient enrollment. The company now has all 49 sites up and running and patient enrollment rates have accelerated. As has been previously reported, and in agreement with the FDA, WM CLOVER-WaM is a single arm, open label trial with a target enrollment of 50 patients. With the support of a $2 million grant from the National Institute of Health’s National Cancer Institute the company plans to initiate a Phase 1b study in pediatric high-grade gliomas in the third quarter of 2023. The study objective is to identify the recommended iopofosine I 131 Phase 2 dose in pHGG patients. The NCI grant was in part driven by the Phase 1a trial data demonstrating a near tripling of the progression free survival typically observed in relapsed/refractory patients. Iopofosine I 131’s ability to cross the blood-brain barrier and recently demonstrated activity in central nervous system lymphoma provides further rationale for treatment of WM patients with CNSL involvement, also known as Bing-Neel syndrome. Based upon achieving a complete response in a CNSL patient treated as part of its Phase 2a trial, the company expanded the CNSL cohort to further evaluate iopofosine I 131 in this indication. Currently, there are no approved therapies available to CNSL patients. Iopofosine I 131 has been evaluated in over 125 multiple myeloma patients including triple class refractory, quad/penta refractory, high-risk and post-BCMA patients with response rates ranging from 40 to 62%. The company’s recently published post BCMA response rate of 50% prompted expansion of this cohort in our ongoing Phase 2a trial. The company’s COO, Jarrod Longcor, will deliver an oral presentation of iopofosine I 131 in multiple myeloma at the Society of Nuclear Medicine and Molecular Imaging Annual Conference. The presentation is on June 26th. Development of the company’s phospholipid ether cancer targeting platform continues to demonstrate its broad utility to provide targeted intracellular delivery of multiple cancer treatment modalities. Preclinical data recently presented at several conferences demonstrate the broad utility of the platform, including: multiple alpha-emitter radiotherapeutic programs targeting solid tumors; the activity of multiple cytotoxic small molecule payloads in triple negative breast cancer mouse models including eradication of the tumors with no subsequent regrowth; the successful delivery, uptake, and gene knockdown in a mouse model of pancreatic cancer with siRNA-phospholipid ether when given intravenously; and, the conjugation and use of peptides against intracellular targets where small molecules may not be effective.