Aleksandra Rizo
Analyst · Cantor Fitzgerald
Thanks, Olivia, and good afternoon, everyone. Due to its novel mechanism of action, imetelstat remains unique in comparison to the currently available treatment in myelofibrosis as well as other investigational agents in Phase III clinical trials today. The overall survival data from our IMbark Phase II clinical trial in the Intermediate-2 or high-risk MF patients, relapsed or refractory to JAK inhibitor, highlights the potential clinical benefit achievable with imetelstat treatment and indicate the potential disease-modifying activity of the drug. Today, there are limited treatment options available for patients who become relapsed or refractory to JAK inhibitors and discontinue ruxolitinib. Approximately 75% of patients discontinued treatment with ruxolitinib, as you might know, within 5 years. And median survival after discontinuation is dismal and has been reported to be 14 to 16 months. Meanwhile, as we have previously reported, the median overall survival in IMbark was 28.1 months, And it was similar for both refractory and relapsed patients. This potential improvement in overall survival associated with imetelstat treatment, was further corroborated by rigorous real-world data analysis from patients treated with best available therapy at the multi-cancer center, who are closely matched for demographic and disease characteristics with imetelstat-treated patients from IMbark. In those analysis, the patients treated with BAT had a median overall survival of approximately 12 months compared to the imetelstat-treated IMbark patients who had an overall survival of approximately 30 months. A few weeks ago, we announced the 3 abstracts were accepted for poster presentations at the upcoming European Hematology Association or EHA Annual Congress. These abstracts report the recent IMbark data analysis and provide further support to the OS results from IMbark. In one of the abstracts, the new data analysis suggested that the improvement in overall survival and IMbark correlate with other clinical benefits observed in its trial, most notably with fibrosis improvement as well as symptom and spleen response. The second abstract reports improvement in OS in triple-negative MF patients treated with imetelstat in IMbark. Triple-negative patients represent a patient subpopulation that affects the 3 driver mutations in myelofibrosis and that have a poor prognosis. The third abstract reports biomarker data, indicating on-target, dose-dependent distribution of telomerase after treatment with imetelstat, and this correlated with the improvement in overall survival in IMbark. Taken together, we believe that the 3 MF abstracts substantiate the OS data observed in IMbark and support the plans with 3 clinical trials in refractory myelofibrosis. Let me now discuss the planned Phase III trial in a bit more detail. Since we disclosed, we discussed this trial design with the FDA, and they agree that we could move forward, which will be an open-label, one randomized Phase III trial of imetelstat compared with best available therapy in approximately 320 patients with Intermediate-2 or high-risk MF for refractory to JAK inhibitor treatment. Patients eligible for the trial will be required to be refractory to a JAK inhibitor, defined as patients who have had an adequate -- inadequate spleen response or symptom response after treatment with a JAK inhibitor for at least 6 months and who had received an optimal dose of a JAK inhibitor for at least 2 months during the treatment period with a JAK inhibitor. Given this definition, we believe that refractory MF patients meeting these criteria will not benefit from further JAK inhibitor treatment, which is why the control arm of best available therapy will exclude JAK inhibitors. In the imetelstat treatment arm, 9.4 milligrams per kilogram of imetelstat will be administered intravenously every 3 weeks. As Chip mentioned, the primary end point for the trial is planned to be overall survival. And we believe this is the first trial in refractory myelofibrosis to use overall survival as a primary end point. Planned key secondary end points include symptom response, spleen response, progression-free survival, complete and partial response, clinical improvements, duration of response, safety, pharmacokinetics and patient-reported outcomes. The trial has been designed to have more than 80 -- 85% power to detect a 40% reduction in the risk of death for imetelstat-treated patients. In making these power calculations and starting the trial size, we assumed a hazard ratio of 0.6 and a one-sided alpha of 0.025. For example, we made the assumption that the best available therapy arm will have a median overall survival of 14 months and the imetelstat arm will have a median overall survival of 23 months. The final analysis for OS is planned to be conducted after more than 50% of the total enrolled patients have died. An interim analysis of OS, in which the alpha spend is expected to be approximately, 0.01, is planned to be conducted after approximately 70% of the total projected number of deaths for the final analysis have occurred. At the interim analysis, if the prespecified statistical OS criterion is met, then we expect such data may support registration of imetelstat in refractory MF. If the prespecified OS criterion is not met at an interim analysis, the trial will continue to a final analysis. Currently, we expect to engage over 150 sites across North America, South America, Europe and Asia. Start-up activities have already begun and we plan to open the trial for screening and enrollment in the first quarter of 2021. Under current assumptions, we expect to complete patient enrollment in the second half of 2022, to conduct an interim analysis in the first half of 2023 and to conduct a final analysis in the first half of 2024. However, both the interim and the final analysis are event-driven and could occur on a different time line than currently expected. We believe that in this planned Phase III trial in refractory MF, if successful, imetelstat will be the first drug to demonstrate a survival benefit in this poor prognosis patient population. Moving on to the ongoing IMerge Phase II/III clinical trial in lower-risk MDS. As of the end of April 2020, approximately 68% of the originally planned clinical sites for the IMerge Phase III clinical trial in lower-risk MDS were opened for enrollment. As we previously announced, COVID-19 has had a significant impact on site initiation and enrollment in this trial. We're doing everything we can to ensure we meet our enrollment goals in IMerge. This has included consistent contacts with our clinical investigators and working with our CRO on enrollment-boosting activities. Now on top of those activities, we are currently evaluating the addition of potentially 6 new countries and approximately 40 new clinical sites for participation in the trial, which could result in a total of up to approximately 130 sites. As for top line results, the protocol-defined final analysis will be conducted 16 months after the last patient is enrolled, and that's based on our updated enrollment exceptions. We expect top line results to be available in the second half of 2022. Compelling data from the Phase II portion of IMerge continue to highlight the differentiating effect of imetelstat in lower-risk MDS patients. First, our data indicates meaningful transfusion independence, or TI, achievable with imetelstat treatment at 42% of patients achieved the primary end point of 8-week TI and 68% achieved hematologic improvement-erythroid. Second, similar rates of clinical benefit, including TI, have been observed in both RS-positive and RS-negative patient subgroups. RS-positive patients represent approximately 10% to 25% of lower-risk MDS patients, while RS-negative patients represent approximately 75% to 90% of the lower-risk MDS patients. Being able to show transfusion independence across these patient subgroups allows imetelstat to potentially address a broad patient relation. Third and the most significant differentiator of imetelstat in lower-risk MDS, which is observed to date, is the durability of transfusion independence. Namely, this year's EHA abstract, which was accepted for an oral presentation, reported a 24-week TI rate of 32%. For the first time, we are now reporting a 1-year TI rate of 29%, representing patients being transfusion free for at least 1 year with the longest transfusion-free period being 2.7 years. In addition, the new median duration of transfusion independence is 88 weeks, which is, to our knowledge, the longest reported to date in the non-del(5q) lower-risk MDS [indiscernible]. Finally, 75% of the 8-week RBC-TI responders showed a hemoglobin rise greater than 3 grams per deciliter during the transfusion-free interval when compared to their pretreatment level. A hemoglobin rise of this magnitude is not achievable with a blood transfusion or growth factor treatment. We believe that the increase of hemoglobin, together with the durability of TI, is indicative of the disease-modifying activity with imetelstat treatment, which aligns with imetelstat's mechanism of action. As a telomerase inhibitor, imetelstat has potential to inhibit the uncontrolled proliferation of malignant stem and progenitor cells and potentially enable recovery of normal hematopoiesis. Now I'd like to hand the call back to Chip. Chip? Chip, are you maybe on mute?