Cellectar Biosciences Secures $140M, Posts 61.8% MRR and 83.6% ORR
Cellectar Biosciences secured up to $140 million in financing to advance its Iopofosine I-131 Phase 3 study for relapsed/refractory Waldenström Macroglobulinemia and FDA accelerated approval filing. The Phase 2b CLOVER-WaM data showed a 61.8% major response rate, 83.6% overall response rate and 13.5-month progression-free survival after 12-month follow-up.
1. Q1 Financing and Cash Position
In May 2026, Cellectar raised up to $140 million through an oversubscribed financing led by Nantahala Capital, generating $35 million upfront and up to $105 million in milestone-based securities. As of March 31, the company held $8.3 million in cash, and net proceeds of about $31 million are expected to fund operations into Q2 2027.
2. Positive CLOVER-WaM Phase 2b Data
The Phase 2b CLOVER-WaM study in 55 relapsed/refractory Waldenström Macroglobulinemia patients achieved primary and secondary endpoints at 12 months, with a 61.8% major response rate, 83.6% overall response rate, 14.5% VGPR/CR rate, 98.2% disease control rate, median progression-free survival of 13.5 months and median duration of response of 17.8 months.
3. Phase 3 Confirmatory Trial and Regulatory Path
Cellectar plans a randomized comparator Phase 3 study of Iopofosine I-131 enrolling approximately 100 patients per arm with full enrollment projected within 18–24 months, aiming for FDA accelerated approval submission. The company is also preparing a Conditional Marketing Approval filing with the EMA for post-BTKi refractory WM patients.
4. Initiation of CLR 125 Phase 1b Trial
The first patient has been dosed in the Phase 1b dose-finding study of CLR 125 in refractory triple negative breast cancer, with dosimetry, safety and efficacy updates expected mid-2026 as additional sites are activated.