Safety and Activity Data Reviewed From First Cohort of Patients; CLR 131 Performance Triggers Advancement Into Second Cohort at Higher Dose

Madison, WI (Press Release) – Cellectar Biosciences, Inc. (NASDAQ:CLRB), an on­col­ogy-focused bio­tech­nology com­pany, to­day an­nounces data from the first cohort of patients en­rolled in its orphan drug-desig­nated Phase 1 study of CLR 131 in patients with re­lapsed or re­frac­tory mul­ti­ple myeloma. Based on safety and ef­fi­cacy data from the first cohort, the trial’s Data Monitoring Com­mit­tee approved en­roll­ment of the sec­ond cohort of patients with a 50 per­cent escalation in dose level of CLR 131.

The pri­mary objective of the multi-center, open label, Phase 1 dose escalation study is to char­ac­ter­ize the safety and tol­er­a­bil­ity of CLR 131 in patients with re­lapsed or re­frac­tory mul­ti­ple myeloma. Secondary objec­tives in­clude estab­lish­ment of the rec­om­mended Phase 2 dose, both with and without dexa­meth­a­sone, as well as an assess­ment of thera­peutic ac­­tiv­ity.

Prior to their par­tic­i­pa­tion in this study, patients in the first cohort had re­ceived a min­i­mum of three sys­temic regi­mens and up to 12 lines of ther­apy.

“Judging by the results of the first cohort, I be­lieve there is sig­nif­i­cant poten­tial for CLR 131 as a safe and tol­er­able treat­ment modality for re­lapsed or re­frac­tory mul­ti­ple myeloma,” stated Sikander Ailawadhi, MD, senior asso­ci­ate con­sul­tant, Division of He­ma­tol­ogy/Oncology, Department of Medicine, The Mayo Clinic, Jacksonville, Florida, and the site's lead in­ves­ti­ga­tor. “I be­lieve initiating the sec­ond cohort of the trial will provide addi­tional useful in­­for­ma­tion, both in terms of estab­lish­ing an appro­pri­ate treat­ment dose, as well as fur­ther under­stand­ing the com­­pound’s poten­tial in this indi­ca­tion.”

Data from the first cohort of patients in the Phase 1 study dem­onstrated safety and tol­er­a­bil­ity with a fa­vor­able adverse event profile. Addi­tionally, stable dis­ease was achieved in four of five treated patients with two of these patients main­taining stable dis­ease throughout the 85-day study monitoring period.

“Importantly, these data collectively dem­onstrate safety and tol­er­a­bil­ity in heavily pre-treated mul­ti­ple myeloma patients as well as provide promising signals of ac­­tiv­ity,” said Jim Caruso, pres­i­dent and CEO of Cellectar Biosciences. “These early out­comes and feedback from the in­ves­ti­ga­tors are en­cour­ag­ing and we look for­ward to fur­ther eval­u­ating CLR 131 in the sec­ond cohort to de­ter­mine optimal dose and regi­men. More globally, these results provide us with fur­ther con­firmation on the utility of our PDC de­livery plat­form, which we be­lieve is in­stru­mental to these out­comes.”

The com­pany is devel­op­ing CLR 131, its lead radiotherapeutic phos­pho­lipid drug con­ju­gate (PDC), for the treat­ment of mul­ti­ple myeloma through the targeted de­livery of iodine-131 to myelomatous cells.

About Cellectar Biosciences, Inc.

Cellectar Biosciences is devel­op­ing phos­pho­lipid drug con­ju­gates (PDCs) de­signed to provide cancer tar­geted de­livery of diverse onco­logic pay­loads to a broad range of cancers and cancer stem cells. Cellectar's PDC plat­form is based on the com­pany's pro­pri­e­tary phos­pho­lipid ether analogs. These novel small-molecules have dem­onstrated highly sel­ective uptake and retention in a broad range of cancers. Cellectar's PDC pipe­line in­cludes prod­uct can­di­dates for cancer ther­apy and cancer diagnostic imaging. The Com­pany's lead thera­peutic PDC, CLR 131, uti­lizes iodine-131, a cytotoxic radioisotope, as its pay­load. CLR 131 is cur­rently being eval­u­ated under an orphan drug designated Phase 1 study in patients with re­lapsed or re­frac­tory mul­ti­ple myeloma. The com­pany is also devel­op­ing PDCs for targeted de­livery of chemo­ther­a­peutics such as paclitaxel (CLR 1603-PTX), a pre­clin­i­cal stage prod­uct can­di­date, and plans to ex­pand its PDC chemo­ther­a­peutic pipe­line through both in-house and col­lab­o­rative R&D efforts. For addi­tional in­for­ma­tion please visit www.cellectarbiosciences.com.

This news re­lease con­tains for­ward-looking state­ments. You can identify these state­ments by our use of words such as "may," "expect," "be­lieve," "antic­i­pate," "intend," "could," "esti­mate," "con­tinue," "plans," or their neg­a­tives or cognates. These state­ments are only esti­mates and predictions and are subject to known and unknown risks and un­cer­tain­ties that may cause actual future ex­peri­ence and results to differ ma­teri­ally from the state­ments made. These state­ments are based on our cur­rent beliefs and ex­pec­ta­tions as to such future out­comes. Drug discovery and devel­op­ment in­volve a high degree of risk. Factors that might cause such a ma­teri­al dif­fer­ence in­clude, among others, un­cer­tain­ties re­lated to the ability to raise addi­tional capital, un­cer­tain­ties re­lated to the ability to attract and retain part­ners for our tech­nolo­gies, the identi­fi­ca­tion of lead com­­pounds, the suc­cess­ful pre­clin­i­cal devel­op­ment thereof, the com­ple­tion of clin­i­cal trials, the FDA review process and other gov­ern­ment reg­u­la­tion, our pharma­ceu­tical col­lab­o­rators' ability to suc­cess­fully de­vel­op and com­mer­cial­ize drug can­di­dates, com­pe­ti­tion from other pharma­ceu­tical com­pa­nies, prod­uct pricing and third-party reim­burse­ment. A com­plete description of risks and un­cer­tain­ties re­lated to our business is con­tained in our periodic reports filed with the Se­cu­ri­ties and Ex­change Com­mis­sion in­­clud­ing our Form 10-K/A for the year ended De­cem­ber 31, 2014. These for­ward-looking state­ments are made only as of the date hereof, and we disclaim any obli­ga­tion to up­date any such for­ward-looking state­ments.

Source: Cellectar Biosciences.