Sarah Gheuens
Analyst · various risks, uncertainties and other factors, including those set forth in our most recent filings with the SEC and any other future filings that we may make with the SEC. On the next slide, we have the agenda for today's call. With me today from Agios are Brian Goff, chief executive officer Cecilia Jones, chief financial officer Tsveta Milanova, chief commercial officer and Dr. Sarah Gheuens, chief medical officer and head of research and development. Following prepared remarks, we will open the call for questions. With that, I am pleased to turn the call over to Brian
Thank you, Sveta. Next slide, please. Our pipeline is focused on advancing our leadership in rare hematology. Mitapivat anchors the portfolio with broad global approvals in PK deficiency and thalassemia. In sickle cell disease, we are in labeling discussions with the FDA, including elements of a potential REMS, and we have filed for approval in Saudi Arabia. We also continue to advance our pediatric thalassemia program. ENERGIZE-Kids and ENERGIZE-KidsT have the potential to expand our addressable US thalassemia population by approximately 2,000 pediatric patients. Beyond mitapivat, we are advancing cevidoplenib in immune thrombocytopenia towards a phase 3 trial planned for the first half of 28 and AG-236 in polycythemia vera toward the phase 3 program by year end. Finally, we look forward to proof of mechanism data for AG-181 in ketonuria before the end of the year as well. Next slide, please. We are excited to share new clinical data at the 26 American Society of Hematology Annual Meeting next month across our rare hematology portfolio, which were highlighted by abstracts released yesterday. In December, we will present new clinical data from the RISE UP Phase 3 trial that we believe meaningfully differentiates mitapivat profile in sickle cell disease, both on hemoglobin and beyond. Potentially driven by mitapivat's unique mechanism of action, targeting both PKR expressed in red blood cells and PKM2 expressed in organ tissues. First, durability. In the open-label extension period, hemoglobin increases are maintained and more patients continue to show response with continued treatment. 62.7% of patients achieved the hemoglobin improvement in the open-label extension period, including 39.7 percent of patients who were initially non responders. And hemoglobin response reaching up to 115 weeks in the open-label period. Second, we are seeing emerging kidney and cardiac data from post hoc analyses of RISE UP. In sickle cell disease, hyperfiltration as measured by an abnormally high eGFR is an early sign of kidney damage. In patients with hyperfiltration, mitapivat reduced eGFR towards normal, a mean change of -14.7 versus -4.9 with placebo at week 52. Importantly, this kidney effect was independent of hemoglobin response suggesting the potential for a PKM2 mediated effect beyond anemia correction. In the heart, hemoglobin responders showed favorable remodeling with a mean reduction in left ventricular mass index of -5.9 grams per meter squared, compared with increases of +5.8 in nonresponders and +4.6 on placebo. Left atrial volume was also reduced supporting the potential for disease modifying benefits. Taken together, these data suggest mitapivat's unique action on PKM2 may address organ damage, a key driver of premature mortality in sickle cell disease. Next slide, please. Also at ASH 26, we will present the first clinical data for AG-236, our siRNA-targeted TMPRSS6 inhibitor for polycythemia vera. From our Phase 1 study in healthy volunteers. AG-236 is designed to raise hepcidin and limit the iron available for red blood cell production, which can control hematocrit in polycythemia vera. A single dose increased hepcidin by up to 24 micrograms per liter at day 29 compared with a decrease on placebo. AG-236 also reduced transferrin saturation in hematocrit, with effects on iron, transferrin saturation, hemoglobin, and hematocrit sustained through month 6. AG-236 was well tolerated with all adverse events Grade 1 or 2 and no serious adverse events or discontinuation. This single dose durability supports the potential for every-6-month dosing and global key opinion leader feedback describes this as a potential paradigm shift in the treatment of polycythemia vera. We look forward to presenting the full 6-month data at ASH next month and updating you on the progress of this program with Phase 2/3 initiation anticipated by the end of this year. Next slide, please. Ahead of Phase 1b proof of mechanism data, we are sharing for the first time preclinical data for AG-181, our novel PAH stabilizer for the treatment of phenylketonuria or PKU. In our preclinical model of classical severe PKU, AG-181 produced significant dose response reductions in blood phenylalanine, and at 300 milligrams per kilogram, we achieved the clinical target of below 360 micromolar without diet modification. In our Phase 1 healthy volunteer study presented at the Society for the Study of Inborn Errors of Metabolism 2026 Annual Symposium, human exposures at our Phase 1b doses were comfortably within the range of efficacious exposures in mice. AG-181 was well tolerated with no serious or Grade 3 or higher adverse events and no discontinuations. And its pharmacokinetic profile supports twice daily dosing in our ongoing Phase 1b study in PKU patients. We believe AG-181 offers a meaningful mechanism for the treatment of PKU supported by compelling preclinical data and phase 1 data in healthy volunteers. Look forward to building on that foundation with Phase 1b proof-of-concept data in PKU patients before the end of the year, which we believe will position the program for further development and its potential to become a transformative medicine for this community. With that, please move to the next slide, and I will hand the call back to Brian for closing remarks.