Jarrod Longcor
Analyst · Ladenburg. Your line is open
Thank you, Jim. Despite recent advances and expansion of treatment options for multiple myeloma, this disease remains an area of high-unmet medical need. And that the course of the disease results in nearly all patients experiencing multiple rounds of relapse or the development of refractory disease with the time to progression accelerating with each successive round of therapy. The greatest needs remain the development of therapies that can provide improved progression free survival and extension of the life expectancies for these patients. Given that currently there are limited treatment options available that offers significant improvement on overall survival in the refractory setting and based on the clinical benefits related to overall survival and progression-free survival already observed with CLR 131 in this heavily pretreated relapsed refractory patient population, we remain optimistic regarding the potential clinical and quality of life benefits CLR 131 may provide to patients with relapsed refractory multiple myeloma. As Jim stated earlier, we completed the third cohort and since initiated the fourth cohort of our Phase 1 clinical study in this difficult to treat patient population, evaluating the safety and tolerability of escalating doses of CLR 131. Based on our evaluation to date, both safety and efficacy signals are extremely encouraging. This is particularly important when you factor in that this performance reflects a 30-minute infusion of just a one single dose of CLR 131. For reference, our Phase II trial will also include a potential second dose and we are exploring the benefits of both approaches. It is also worth noting that the overall clinical benefit rate for this study is 86%, despite patients receiving an average of four prior treatments including stem cell transplantation and triple drug combinations. As of March 2, 2017 the patients in Cohort 1 and Cohort 2 have demonstrated post treatment median overall survival of 17.7 months and 8.4 months respectively. The median overall survival for all evaluable patients in both cohorts continues to increase. And we will continue to follow them to determine overall survival benefit. Currently, the final median overall survival for each cohort is not yet evaluable as all patients continue to be followed. All evaluable patients in the clinical study have experienced progression-free survival as well. In Cohort 1, subjects experienced a median progression-free survival of 93 days, while patients in Cohort 2 have already achieved a median progression-free survival of 133 days and counting as of February 28, 2017. The average and median progression-free survival on Cohort 2 is still increasing, because one of the four patients in that cohort continues to experience progression-free survival. I would like to point out that with a 50% increase in the dose from Cohort 1 to Cohort 2, CLR 131 produced a 45% increase in the median progression-free survival and over a 50% increase in the average progression-free survival experienced by these patients. As we previously stated, while it is premature to report survival related efficacy data from Cohort 3, all patients in Cohort 1 and 2 continue to experience overall survival benefit. Patients from Cohort 1 who received a single 12.5 millicuries per meter squared dose have experienced to date the median overall survival of 17.7 months. Cohort 2 patients who received a single 18.75 millicuries per meter squared dose have a current median overall survival of 8.4 months. To put this in context, while no head-to-head studies have been conducted between CLR 131 in other therapies, a 2016 article published in the peer reviewed journal Bone Marrow Transplantation did show that those patients evaluated that, where refractory to both proteasome inhibitors and immunomodulatory drugs have a median overall survival of 9 months and a progression-free survival of only five months. All patients enrolled in Cohort 1 and Cohort 2 were previously treated with both proteasome inhibitors and immunomodulatory drugs and experienced these progression prior to enrollment in our Phase 1 study. In addition, as we recently announced similar to the comparison of Cohort 2 versus Cohort 1, patients in Cohort 3 experienced a more substantial and sustained reduction in the surrogate marker M-protein. The average reduction of M-protein in Cohort 3 peaked at Day 43 and was nearly a threefold increase in the reduction seen in Cohort 1, and nearly a twofold increase in the reduction over Cohort 2. Patients' M-protein levels continue to be well controlled from a single 30-minute infusion of CLR 131, through Day 64 post-infusion with patients experiencing greater than a twofold reduction in M-protein at this time point in Cohort 3 over both Cohort 1 and Cohort 2. M-protein is one of several surrogate markers of efficacy that we have been using to predict potential future results. And we are very pleased with the outcomes to date in this regard. As impressive as our efficacy data has been, the demonstration of efficacy is a secondary outcome in the Phase 1 trials. The primary endpoint is the identification of the maximum tolerated dose and an understanding of the safety and tolerability of CLR 131 in the previous doses. To date, we have not reached the maximum tolerated dose and we have observed an excellent safety profile, which has been similar for all three cohorts to date. Patients in Cohorts 1, 2 and 3 expand an average of 4.75, 4.25 and 7.0 adverse events per patient respectively. The average of severity grade of the adverse events per patient were 2.05 and 2.71 in [Technical Difficulty] and 2. While in Cohort 3, the average grade was 2.57 per patient. It is important to note that while the average number of adverse events per patient increased in Cohort 3, the severity of these adverse events decreased from that seen in Cohort 2. We believe that this favorable adverse event profile is due at least in part to our PDC targeting of the tumor and sparing healthy tissue. Our most common adverse events continue to be select cytopenias that have not resulted in any clinically relevant events. As discussed, we have completed the safety evaluation portion of the third cohort, which had - was a single 25 millicuries per meter squared dose. The data monitoring committee deemed this dose to be safe and well tolerated and we have therefore initiated enrollment of the fourth cohort at a single 30-minute infusion of 31.25 millicuries per meter squared, which represents a 25% increase from the 25 millicuries per meter squared dose used in cohort 3, and a 150% increase over Cohort 1's dose. We plan to provide a data update on the fourth cohort and third cohorts later this year. Equally as important at the beginning of quarter four, we announced the design of our NCI-supported Phase 2 study of CLR 131 in relapsed/refractory multiple myeloma in other select hematologic cancers. Originally, the company provided guidance that this study would be initiated in the first half of 2017. Thanks to a collective team effort, which includes Cellectar employees, our contract research organization, investigators and consultants, we accelerated our study initiation guidance to the first quarter of 2017 and announced that preliminary efficacy data was expected in the second half of 2017. The Phase 2 study design was carefully constructed to optimize our understanding of CLR 131 by further defining its clinical benefits in both a single and multi-dose regime for the treatment of relapsed/refractory multiple myeloma. The results of which we believe will be instrumental in the design of a pivotal clinical trial. Based on our evaluation, we believe CLR 131 may also provide therapeutic benefits in a number of orphan-designated, difficult to treat hematological cancers that are clinically and commercially attractive in design, the Phase 2 study to rapidly and cost effectively explore the drug's broader clinical utility. The Phase 2 study will be conducted in up to 15 centers across the United States. We expect that all patients will receive a single dose of CLR 131 at 25 millicuries per meter squared infused over approximately 30 minutes, with the option of a second dose occurring between 75 and 180 days later, based upon physician assessment. Currently, those patients in the trial with multiple myeloma will also be receiving 40 milligrams - I'm sorry about that - concurrently those patients in the trial with multiple myeloma will also be receiving 40 milligrams oral dexamethasone weekly for up to 12 weeks. The primary endpoint for the study is Objective Response Rate or ORR; secondary endpoints include progression-free survival, median overall survival and other measures of efficacy. In relapsed/refractory multiple myeloma patients' efficacy responses will be determined according to the latest International Multiple Myeloma Working Group Criteria, while those in the lymphoma arms efficacy will be determined according to the Lugano criteria. Now I'd like to transition to provide a brief update on the progress in our development collaboration with Pierre Fabre. As reported in December, we have completed work on producing multiple phospholipid drug conjugates with the compounds provided by Pierre Fabre, and are under way conducting our in vitro and in vivo screening studies for a variety of solid tumors. We will continue to provide updates on those studies as the data become available. With that, it's my pleasure to turn the call back to Jim.