Jim Dentzer
Analyst · Cantor. Please go ahead with your question
Thank you, Bill. Good afternoon everyone and thank you for joining us today. Our mission at Curis is to develop the next generation of targeted cancer therapies to meaningfully improve and extend patients' lives. In the third quarter, we made significant progress on that mission. Despite the difficulties of the COVID-19 pandemic, we remain on track to achieve all of our stated goals and milestones for 2020, as we prepare for the anticipated release of clinical results next month at ASH. With CA-4948, our first-in-class IRAK4 inhibitor, we have two ongoing clinical studies. One, in patients with relapsed or refractory non-Hodgkin's lymphoma and a second IRAK4 study in patients with relapsed or refractory acute myeloid leukemia and high-risk myelodysplastic syndromes. Updates from both studies will be presented in an oral presentation and in poster sessions next month at the annual meeting of the American Society of Hematology. In addition, earlier today, we were very pleased to announce that we have entered into a cooperative research and development agreement or CRADA with the National Cancer Institute, under which they will collaborate with us on the development of CA-4948. We are thrilled to announce this partnership as it substantially increases the number of reachable patients in a population of dire medical need without requiring an external diluted financing or sizeable financial commitment from Curis. We are eager to begin the collaborative process with our partners at the NCI, and we look forward to providing you with updates as we have them. With CA -- with CI-8993, our progress has also been very exciting. Earlier this year, we announced our partnership with ImmuNext and the submission of our IND for CI-8993, our first-in-class VISTA inhibitor. In Q2, we announced that we received FDA clearance of that IND. Today we are happy to report that in Q3 we were able to get our first clinical sites up and running and initiate dosing in our Phase 1a/1b study in patients with relapsed or refractory solid tumors. All told, it was a very active quarter for Curis. We look forward to building on this progress through our year-end data updates and carrying that momentum into 2021. Now let's dig into some detail on our ongoing clinical programs. As a refresher, our Phase 1 dose escalation study of CA-4948 for the treatment of patients with relapsed or refractory non-Hodgkin's lymphoma includes patients with diffuse large B-cell lymphoma, Waldenström's macroglobulinemia and oncogenic MYD88 mutations. We are currently evaluating patients treated with 300 milligrams of CA-4948, twice daily after observing clear dose response and tumor reductions at previous dose levels. Last week, on November 4th, we disclosed clinical data from this study in an abstract that was accepted for oral presentation at the ASH conference in December. As reported in the abstract CA-4948 has exhibited encouraging safety and pharmacokinetic properties. And at higher dose levels, clear single agent efficacy in a relapsed refractory NHL patient population that had already seen a median of four prior lines of therapy before joining our study. To provide some additional context, last year at ASH, we presented a small but intriguing data set that suggested CA-4948 could potentially establish IRAK4 inhibition as a new mechanism of action, a novel way to treat patients with NHL as it delivered a compelling safety and efficacy profile, particularly at higher dose levels in a monotherapy setting. This year's goal was to confirm that finding and also explore which of the efficacious dose levels of 200, 300 or 400 milligrams BID offered the best balance of safety and efficacy. Diving a bit deeper into the abstract data, which are from a July cutoff, we see that eight patients achieved a tumor burden decrease of 20% or greater from baseline, including four of the patients treated with 300 milligrams BID. It is very encouraging that efficacy improved as dose levels increased. This was shown in both the study group as a whole, and also in the case of a single patient, a Waldenström's patient who as of the July cutoffs had been on study for 18 months over multiple dose levels and achieved an objective response with a 66% tumor burden reduction. This patient started at an initial BID dosage of 50 milligrams and escalated through 100 milligrams, 200 milligrams and 300 milligrams, demonstrating dose dependent decreases in tumor burden at every level. It is important to highlight again that these are extremely sick patients who have received a median of four prior lines of therapy before entering the study, that we have been able to observe therapeutic effect in monotherapy, and the dose effects are durable over such an extended period of time is enormously encouraging. And we look forward to the ASH conference where we will provide an updated and expanded dataset with a later cutoff date for the data provided in the abstract. Given the clear single agent activity we have seen in the clinic and the clear preclinical synergy we have seen when CA-4948 is combined with a BTK inhibitor, such as ibrutinib. We and our clinical investigators are eager to explore the combination of CA-4948 and ibrutinib in the clinic. As we mentioned on our August call, we could already see where the data were headed and we made the decision to get the combination study up and running as quickly as possible. Today we are excited to announce that in working closely with our clinical sites, we have been able to amend the protocol of our existing study to include combination therapy rather than having to file a completely new protocol and initiate a completely new clinical study. This allows us to leverage the clinical sites and staff currently active in our monotherapy study and should save significant time and resources as we speed our path to the clinic. The combination study has two parts, and it will be designed -- and it will be outlined in a trial in progress poster to be presented at the ASH conference. Part one of the study design will be dose escalation, a 3x3 design with CA-4948 doses starting at 200 milligrams BID and escalating to 300 milligrams BID and ibrutinib doses appropriate for the respective NHL subtype. Part two of this study will be an expansion basket of four cohorts. The first in Marginal Zone Lymphoma or MZL. The second in ABC DLBCL. The third in primary central nervous system lymphoma or PCNSL and the fourth in NHL with adaptive ibrutinib resistance. Primary endpoints in the study will include the established clinical end points such as objective response rate and duration of response. But we will also explore response correlation with biomarkers we have identified that may help us enrich the patient population and help us determine the optimal path for registration. So far from scientific hypothesis to preclinical data to clinical data, each step of the journey has been a consistent step forward in the long-term vision for CA-4948 in NHL. That IRAK4 controls a critical pathway that is parallel to and complimentary to the BTK pathway. And that inhibiting IRAK4 can provide incremental benefit to the vast population of patients treated with a BTK inhibitor and may help mitigate resistance to BTK therapy. That is our vision in NHL. Now let's move on to leukemia, and what many see as even more exciting than the NHL vision. Our second study of CA-4948 is in patients with relapsed or refractory AML and high-risk MDS, including those with spliceosome mutations that drive the expression of the oncogenic long isoform of IRAK4. In early July, we announced the dosing of the first patient in our open-label Phase 1 dose escalation study of CA-4948 monotherapy in these patient populations. Since then, enrollment has proceeded particularly well. You may recall that this study grew out with a groundbreaking work performed by Dr. Amit Verma and Dr. Daniel Starczynowski presented at last year's ASH conference in which they identified the specific spliceosome mutations that drive disease in AML and MDS patients by causing the expression of the long isoform of IRAK4. We now know based on their published work, that the long isoform of IRAK4 is oncogenic and further that IRAK4-L is overexpressed in over half the population of AML and MDS patients. Of particular excitement to the team here at Curis, doctors Verma and Starczynowski also demonstrated that inhibiting IRAK4-L with a treatment of CA-4948 substantially reduces leukemic blast formation in patient-derived xenografts. Today, we are pleased to announce that the first two cohorts in the Phase 1 dose escalation study have completely enrolled. The first cohort receives 200 milligrams twice daily, and the second cohort receives 300 milligrams twice daily. As we have previously discussed, we believe 200 milligrams is likely to be a therapeutic dose, and we will continue dose escalation until reaching the recommended Phase 2 dose and maximum tolerated dose. We will provide an additional overview of the study design and report initial interim data for these patients next month. We know that other drugs in single agent studies in this late line relapsed refractory population have struggled to show steep reductions in leukemic blasts cells. To be clear, the data we will be presenting next month will be early data. Nevertheless, we hope to see data consistent with our preclinical findings. We remain confident that the novel approach of targeting IRAK4 represents clear differentiation for CA-4948 in AML and MDS. Before moving on, I would like to add that this AML and MDS study and the data we are presenting next month are in addition to the NCI CRADA we announced earlier today. We are still in the early days of our partnership with NCI, and we look forward to providing you with updates on our partnership in the future. Now I'd like to turn to CI-8993. We believe that a therapeutic antibody, such as CI-8993, could provide potent VISTA blockade as a monotherapy in patients with certain solid tumors. This is a target we have long been excited about, because of the critical role it plays in suppressing T cell activity when at the VISTA checkpoint is activated. Conversely, blocking VISTA has been shown in preclinical studies to prevent T cell suppression and thereby reactivate antitumor immune function. We also see significant combination potential and in the future may explore targeting VISTA in combination with a PD-1, PD-L1 or even a CTLA4 inhibitor as preclinical study suggests that blocking VISTA significantly improves the efficacy of those checkpoint regulators. To date, there has been little meaningful progress targeting VISTA due to the various on target side effects associated with pathway blockade, most notably immune mediated toxicity and cytokine release syndrome. However, progress in the development of CAR-T therapies and the broader immunotherapy space over the last decade have made safe and effective VISTA regulation much more possible. To that end, we have initiated patient dosing in a Phase 1a/1b dose escalation study evaluating CI-8993 in patients with relapsed and refractory solid tumors and enrollment is currently ongoing. We believe that CI-8993 has the potential to succeed beyond our previous PD-L1 VISTA program, a small molecule that demonstrated activity, but did not provide the level of efficacy needed to compete with monoclonal antibodies in development at the time for the same target population. This is likely because large molecule monoclonal antibodies like CI-8993 provide complete coverage of a receptor across multiple binding regions. By comparison, a small molecule interrupts only one or two contact points on a target receptor. In addition, monoclonal antibodies tend to firmly wrap around a receptor almost like Velcro, as opposed to a small molecule, which continually bounces on and off its target. We believe CI-8993 is the most advanced anti-VISTA antibody currently in clinical development. We have received a lot of interest and excitement from the clinical community on this program, and we believe CI-8993 has the potential to be a game-changing cancer therapy. We look forward to providing an overview of the study in a trial and -- trial and progress poster at SITC this week and providing additional updates in 2021. To wrap up, I want to emphasize how proud I am of the entire team at Curis that in the midst of an ongoing global pandemic has worked tirelessly to ensure we hit every ambitious goal we set for ourselves this year. It is incredible to think that since we signed the deal to bring this new VISTA asset on board in January, we have written a protocol, engaged the FDA, secured IND clearance, opened clinical sites, trained investigators and their staff, and begun the dosing of patients, all in less than 9 months. It is a testament to the team's experience, their commitment and their passion. And it is an honor to work with them. With that, I'll turn the call over to Bill to review our financial results for the quarter. Bill?