Aleksandra Rizo
Analyst · Needham & Company
Thanks, Olivia, and good afternoon, everyone. Before I discuss recently published the imetelstat data, I'd like to give a brief update on our Phase III clinical trials in refractory MF and lower-risk MDS. The clinical protocol for our upcoming Phase III clinical trial in refractory MF, called IMpactMF, has been finalized, and the trial is now listed on clinicaltrials.gov. We continue to expect the trial to be open for screening and enrollment in the first quarter of 2021. Start-up activities are ongoing and include site selection, engagement of vendors, building of the clinical database, among others. In the IMpactMF trial, the final analysis for the primary end point of overall survival, or OS, is event-driven and is planned to be conducted after more than 50% of the patients enrolled in the trial have died. An interim analysis of OS is planned to be conducted after approximately 70% of the total projected number of death events for the final analysis have occurred. If the pre-specified statistically significant difference in OS between the 2 treatment arms is met at the interim analysis, it is possible that data from the interim analysis could support the registration filings. Moving on to the ongoing IMerge Phase III clinical trial in lower-risk MDS. Enrollment for this trial continued to progress in the third quarter. In August, all 92 of the originally planned clinical sites were open for enrollment. To address enrollment delays related to the COVID-19 pandemic experienced earlier this year, we implemented several enrollment-boosting activities. These include engaging clinical science liaisons to interface directly with the clinical sites, establishing a digital presence for the trial, and expanding the number of clinical sites in existing and new countries. We currently expect to open approximately 30 new clinical sites, although at this time only a handful are open. As a result, we believe the full benefit of the additional sites have not yet been realized. We expect almost all of these sites to be open for screening and enrollment by the end of 2020. Our team internally is continuing to target completion of enrollment in IMerge by the end of the first quarter. Despite our efforts, given the recent resurgence of the COVID-19 pandemic particularly in many of the countries where IMerge is being conducted and the uncertainty and unpredictability regarding this impact of clinical trial activities coming for in winter, we now believe it is most likely the trial will be fully enrolled sometime in the second quarter of 2021. However, it is important to note that as long as enrollment is completed by the end of the first half of 2021, we continue to expect top line results to be available in the second half of 2022, which is consistent with our previous guidance. As announced in a press release last week, the data from IMerge Phase II trial in lower-risk MDS was published in the well-respected Journal of Clinical Oncology, or JCO. We believe this publication further indicates the recognition of the importance of the IMerge data by experts in the MDS field. As you may recall, meaningful and durable transfusion independence with imetelstat treatment has been highlighted consistently in previous medical conference presentations, as it is in the JCO article. The median duration of transfusion independence of 21 months is a critical clinical outcome for these transfusion-dependent patients. Moreover, as reported, approximately 30% of the patients were transfusion-free for over a year. To our knowledge, this is the longest duration of transfusion independence reported in lower-risk MDS patients. In addition to the durable transfusion independence, a decrease in SF3B1, one of the key mutations correlated with ineffective erythropoiesis in lower-risk MDS, was observed in the trial although only a small number of patient samples were available for testing. Of critical importance, the duration of the transfusion-free period was correlated with the decrease of the SF3B1 mutation. And patients that had the highest decrease of SF3B1 also had the longest transfusion-free period. To put this data in context, recall that telomerase is continuously upregulated in malignant stem and progenitor cells, resulting in malignant hematopoiesis. As a telomerase inhibitor, imetelstat selectively targets malignant cells, with continuously upregulated telomerase to induce their death and enable potential recovery of normal hematopoiesis. Decrease in disease mutation, such as the SF3B1 mutation, is an indicator of potential impact on the malignant cells of the underlying disease, which suggests disease-modifying activity. In addition, observations of clinical outcomes, such as the durable transfusion-free period experienced by the patients in IMerge Phase II, indicate potential recovery of normal hematopoiesis, suggesting disease-modifying activity. Therefore, we believe both the durable transfusion independent and the reduction in the SF3B1 mutation observed in the IMerge Phase II suggest disease-modifying activity for imetelstat treatment in these patients. Regarding ASH, yesterday we announced that a total of 10 abstracts have been accepted, of which four would be oral presentations. In summary, the data and analysis reported in all of the abstracts support our Phase III clinical trial and highlight the clinical benefits, observed in both the Phase III IMerge and IMbark trial. There are several abstracts covering the IMbark Phase II including new data on patient-reported outcomes, data on improved OS in triple-negative MF patients as well as biomarker data and analysis supporting the on-target activity of the drug. Also, there are two abstracts called trials in progress that provide further details of the trial design for the ongoing IMerge Phase III and the upcoming IMpactMF Phase III. This afternoon, I would like to focus on the data suggesting potential disease-modifying activity of imetelstat from the IMbark Phase II trial in relapsed/refractory MF that were reported in 2 of the ASH abstracts. One of the ASH abstracts, #346 which is scheduled for an oral presentation, reports new analysis from the IMbark Phase II trial that shows significant dose-dependent reduction of the mutation burden of key driver mutations for MF as measured by reduction in the variant allele frequency, or VAF, of the mutation. The data showed that the patients who had reduction in VAF had prolonged median OS of 31 months versus 21 months for those patients that did not have reduction in VAF. The abstract concludes that depletion of cytogenetically abnormal clones and reduction in mutation burden, together with the improvement in median life further demonstrate that imetelstat has disease-modifying activity by targeting malignant cells. The second abstract in MF, #658 which is scheduled for an oral presentation, describes a set of data from the IMbark Phase II showing that there was a correlation between the improvement in fibrosis and improved median OS. In other words, the patients that had at least 1 degree of fibrosis improvement had significantly longer survival than those who had worsening of fibrosis. In conclusion, we believe that the data from the JCO publication and these 2 abstracts highlight imetelstat's impact on the malignant cells, responsible for the underlying disease as well as the clinical outcomes of durable transfusion independence for lower-risk MDS patients and improved overall survival for relapsed and refractory MF patients. Taken together, these data continue to build the clinical and biomarker evidence suggesting disease-modifying activity, which we believe differentiate imetelstat from other treatments for low-risk MDS and refractory MF. Now I'd like to hand the call back to Chip. Chip?