Chris Bowden
Analyst · Credit Suisse. Your line is open
Thanks, David. I won’t be covering all of our programs and trials in detail on this call but wanted first to spend some time on our PKR activators with the announcement that all five of our abstracts have been accepted for presentation at EHA next month. Our two PKR activators, AG-348 and AG-519, are in development for the treatment of pyruvate kinase deficiency, a rare genetic disease where mutations in the PKR enzyme cause hemolytic anemia and associated morbidities. The clinical spectrum of pyruvate kinase deficiency is associated with a range of factors beyond transfusion status. Severe jaundice and anemia can require intensive medical support for some patients. In addition, many patients undergo splenectomy in an effort to control hemolysis. This can be followed by a lifetime of extreme fatigue that limits participation in normal day to day activities. Iron overload is another potential complication. It can be found even in patients with no history of regular transfusions. Iron overload is associated with liver fibrosis, endocrinological abnormalities and cardiac events. Our understanding of pyruvate kinase deficiency continues to evolve with the help of the ongoing natural history study run by Boston Children’s Hospital. This study has enrolled over 200 patients and we expect to present new data in the second half of the year. Our first PKR activator, AG-348, is enrolling in a global Phase 2 trial in adult transfusion-independent patients with pyruvate kinase deficiency. This trial is known as DRIVE PK. DRIVE PK is an open-label, randomized study that includes two arms of up to 25 patients each, receiving 50 or 300 milligrams twice daily for at least six months. Transfusion-independent men and women with a hemoglobin of less than 12 milligrams per deciliter qualify for this study. Routine laboratory and clinical assessments are conducted weekly for the first few weeks, extending to every three to four weeks until week 24. Safety is continuously monitored while patients are on study. At EHA we will be presenting initial data on the first 15 to 20 patients in this ongoing trial. Our goal for this presentation is to begin to address some of the key objectives we’ve laid out for this first-in-patient study – one, understanding the safety and tolerability of AG-348 with long-term dosing; two, confirming exposure of the drug and activation of the PKR pathway in patients; three, assessing changes in hemoglobin levels and other hematologic parameters; four, early assessment of the correlation between clinical effects and mutational background; and, finally, evaluating routine clinical and laboratory safety findings including sex hormones to understand the potential clinical significance of AG-348 aromatase inhibition. As a reminder, patients in this ongoing trial will have varying amounts of follow-up at the time of the EHA presentation. In the separate abstract, preclinical data for AG-348 in beta thalassemia will also be shown at EHA. , we will be presenting preclinical and clinical data from three abstracts at EHA including the Phase 1 single-ascending dose and multiple-ascending dose trials. Since this trial is still ongoing, we plan to present data from the completed single-ascending dose study in addition to some of the multiple-ascending dose data. As a reminder, AG-519 exhibits no preclinical aromatase inhibition. At EHA the initial data from both DRIVE PK and AG-519 will be presented and we look forward to continuing to study the impact that our PKR activators could have on people with pyruvate kinase deficiency. The activation of wild type and mutant pyruvate kinase enzyme by our PKR activators has the potential to help patients with a broad range of hemolytic anemias beyond pyruvate kinase deficiency. We will continue to explore opportunities that expand the utility of these molecules. Moving to our IDH inhibitors, we remain committed to a development strategy of speed and breadth for AML and other hematologic malignancies as we work to give patients who are waiting for more effective and tolerable therapies’ better options. In relapsed/refractory AML we are conducting a set of trials that include two important expansion cohorts for AG-221 and AG-120. And as David mentioned today we announce that AG-221, the expansion cohorts, has completed enrollment. Our Phase 3 identified study for AG-221 in relapsed/refractory AML is ongoing with additional frontline and combination studies for both molecules planned or already underway. In March Celgene initiated a Phase 1-2 frontline combination study of AG-221 or AG-120 with Vidaza in AML. Together with our ongoing Phase 1B frontline combination study of AG-221 or AG-120 with standard of care, intensive chemotherapy, known as 7+3, these trials position us for broad clinical development of our IDH inhibitor in newly diagnosed patients. With our drug’s unique mechanism of action we are looking to change the treatment paradigm for IDH mutant AML, using a long-term differentiation therapy that is distinct from the end targeted effects of chemotherapy, which also carry considerable toxicity. We have now reported on over 300 people with IDH mutant-positive hematologic malignancies treated with AG-221 or AG-120 in our clinical trials. The single-agent activity for these investigational medicines in AML is compelling, based on the overall response rates, durability and the favorable safety profile seen with once-daily oral dosing. Developing our IDH inhibitors in solid tumors remains a priority based on the potential to help a large number of patients in the early encouraging Phase 1 dose escalation data we presented last year. This is a new area of biology with our drug’s unique mechanism of action but one we are committed to exploring further with our ongoing and planned trials. The data we presented at last year’s ACR-NCI-EORTC meeting demonstrated that AG-120 is well-tolerated in a broad set of solid tumor and glioma patients. It demonstrated encouraging signs of prolonged stable disease in low-grade glioma as well as chondrosarcoma in intrahepatic cholangiocarcinoma and demonstrated evidence that 2HG was lower in the brain for some glioma patients, as measured by magnetic resonance spectroscopy. These observations were paired with signs that tumor volume was decreasing, based on MRI volumetric assessments in some glioma patients. And these findings helped shape our ongoing expansion phase, which includes four 25-patient cohorts in low-grade glioma with at least six months of prior stand [ph] second line cholangiocarcinoma, high-grade metastatic chondrosarcoma and a final cohort of solid tumor patients with IDH1 mutations not eligible for cohorts one through three. We remain on track to present data from our AG-120 expansion study in low-grade glioma and initiate a randomized Phase 2 study in IDH1 mutant positive cholangiocarcinoma in the second half of 2016. For AG-881, which is a brain penetrate pan-IDH mutant inhibitor, we are enrolling Phase 1 dose escalation and expansion trials in both heme malignancies and solid tumors. We will keep you updated as these trials progress. I’m now going to turn the call over to Glenn to review our financials.