Sarah Gheuens
Analyst · Scotiabank. Your line is open
Thanks, Brian. Just recently, we were able to attend two significant meetings where we continued engaging with the community. At both the Academy for Sickle Cell and Thalassemia Conference and the SCDAA annual convention, we were reminded once again about the difficult journey for sickle cell patients. And it reinforces our conviction for what we are aiming to bring to patients. Turning to sickle cell disease, we are saddened by the recent events impacting this community and continue to be steadfast in our commitment to deliver a novel oral therapy that potentially improves anemia, VOCs and how patients feel and function, particularly with respect to fatigue. Given the positive data we generated in the Phase 2 portion of the RISE UP study as well as the positive data we have generated in other hemolytic anemia that share a common pathophysiology, we are excited about the potential for mitapivat to become a convenient first-in-class and best-in-class treatment option that improves red blood cell health for patients living with sickle cell disease. As announced last week, we are very pleased that we met our goal of completing enrollment in the Phase 3 RISE UP study by the end of the year, just over a year after we began recruiting this cohort. As a reminder, the Phase 3 study has a planned sample size of 198 subjects randomized 2:1 to mitapivat versus placebo across approximately 100 trial sites globally. There are two primary endpoints, hemoglobin response, defined as an increase of at least 1 gram per deciliter in average hemoglobin concentrations over weeks 24 to 52 compared with baseline and annualized rate of sickle cell pain crises. Driven by a differentiated mechanism of action, we believe that mitapivat has the potential to address the high unmet need in this disease by improving anemia, reducing sickle cell pain crises and making patients feel better. We look forward to reporting top line data from the Phase 3 next year. For thalassemia, we aim to deliver the first therapy approved for all thalassemia subtypes. Based on the positive data generated in both the Phase 3 ENERGIZE study of mitapivat in adults with non-transfusion-dependent alpha or beta thalassemia, and the Phase 3 ENERGIZE-T study of mitapivat in adults with transfusion-dependent alpha or beta thalassemia, we believe mitapivat has the potential to become a foundational and convenient oral treatment option for all subtypes of thalassemia, including all genotypes and all levels of transfusion burden. We are working diligently to progress the filing and continue to expect to file an sNDA by the end of this year, seeking a label that includes adults living with all subtypes of thalassemia. In pediatric PK deficiency, we were pleased to announce top line data from the Phase 3 ACTIVATE-KidsT study of mitapivat in children with PK deficiency, who are regularly transfused. We are proud of this trial because, first, this is the first Phase 3 study to report data in this population and importantly, it's the first completed pediatric study of mitapivat for Agios. While the pre-specified statistical criterion for the primary endpoint was not met, we believe these results were clinically meaningful given the percentage of patients that achieved the transfusion reduction response, including those who had a transfusion-free response with no red blood cell transfusions and those who achieved a normal hemoglobin response, defined as hemoglobin concentrations within normal limits at least once in eight weeks or more after transfusion. And second, safety results from mitapivat were consistent with the safety profile for mitapivat previously observed in adults with PK deficiency who are regularly transfused. With enrollment completed in the Phase 3 ACTIVATE-Kids trial, we look forward to an anticipated data readout next year. In parallel with the progress we continue to make across the mitapivat development program, this quarter, we also made important advancements in our tebapivat program. First, we initiated the Phase 2 study of tebapivat in lower-risk MDS. This open label study will enroll a total of 60 individuals with transfusion-dependent lower risk MDS across three dose levels, 10 milligrams, 15 milligrams and 20 milligrams, each of which is greater than the 5-milligram dose that was evaluated in the previous Phase 2a study. Each dose level cohort will be open for enrollment sequentially, without pauses between the cohorts, meaning that we will first enroll 20 patients in the 10-milligram dose cohort and once those slots are filled, we will begin enrolling 20 patients in the 15-milligram dose cohort and then we will do the same for the third cohort of 20 patients at the 20-milligram dose. There is a 24-week core period for each cohort, followed by a 156-week extension period. The primary endpoint of this study will be transfusion independence, defined as remaining transfusion-free for at least eight consecutive weeks during the core period. Secondary endpoints will include safety, change in hemoglobin and additional measures of anemia. Similar to thalassemia, with this program, we aim to deliver the first oral therapy that addresses anemia due to ineffective erythropoiesis in lower-risk MDS, which affects approximately 75,000 to 80,000 patients in the U.S. and EU5 and accounts for approximately 70% of all MDS cases. Also this quarter, we were delighted to receive FDA orphan drug designation for tebapivat for the treatment of MDS. This underscores the importance of bringing new oral treatment options to patients suffering from this rare disease and we expect to provide additional milestone timelines once enrollment is further along. Looking forward, we are excited to be attending the upcoming annual meeting of the American Society of Hematology, ASH and look forward to the publication of accepted abstracts on November 5. With that, I will now turn the call over to Tsveta.