Jim Dentzer
Analyst · Cantor
Thank you, Bill. Good afternoon, everyone. And thank you for joining us today. As ever, our mission at Curis is to develop the next generation of targeted cancer therapies to meaningfully improve and extend patients' lives. In that regard, 2020 was an especially constructive year for Curis despite the difficulties of the ongoing COVID-19 pandemic. We were fortunate to be able to continue bringing our novel therapeutics to patients enrolled in our clinical studies and maintained a steady pace of progress throughout the clinical process, culminating in a number of exciting updates from our lead assets CA-4948, our first in class IRAK4 kinase inhibitor, released during the Ash annual meeting in December. Presently, our IRAK4 platform is led by two ongoing clinical studies, one in combination with the BTK inhibitor ibrutinib for patients with relapsed or refractory non-Hodgkin's lymphoma, and the second 4948 monotherapy study in patients with relapsed or refractory Acute Myeloid Leukemia or AML and high-risk Myelodysplastic Syndromes or MDS. We are on track to provide a follow up update from this AML MDS study by mid-year and report initial data from the CA-4948 ibrutinib combination study by year end. We also continue to be excited by the potential opportunities that could come out of the Cooperative Research and Development Agreement, CRADA with the National Cancer Institute that we announced in November on the development of CA-4948. And from the IFT being run by Dr. Platzbecker studying CA-4948 as a treatment for anemia in patients with lower risk MDS. We will discuss them in greater detail later on this call. But both partnerships offer a uniquely intriguing expansion potential while also substantially increasing the number of patients we are able to reach in a population of dire medical need and providing a derisked opportunity to further develop CA-4948 in novel indications. Moving away from IRAK4 for a moment; also in 2020, we acquired rights received IND clearance and initiated patient dosing in a Phase 1a/1b trial of CI-8993, our first in class, monoclonal anti VISTA antibody for the treatment of patients with relapsed or refractory solid tumors. We have continued to enroll patients, and bring additional trial sites online for the study and look forward to reporting initial safety and efficacy data in the second half of this year. All told 2020 and the fourth quarter in particular, was a time of meaningful progress for the company, including the successful execution of key strategic financings that have provided a robust foundation to support the continued advancement and expansion of our clinical programs in 2021 and the years to come. We look forward to building on this progress, as 2021 shapes up to be another important year for curious. With that, let's dig into some detail on our ongoing clinical programs starting with leukemia. We're evaluating CA-4948 in patients with relapsed or refractory AML or MDS, including those with spliceosome mutations that drive the expression of the oncogenic long isoform of IRAK4. At Ash, we announced highly encouraging Phase 1 data from our ongoing monotherapy study demonstrating marrow blast reductions observable in all evaluable patients, with two of six valuable patients experiencing a marrow complete response. Since the last update, we have continued to gather data. And we have begun dosing patients at 500 milligrams BID. After early indications at preceding doses were in line with what we had previously reported. We are looking forward to presenting updated data from this study by mid-year. Separate from this trial; we're especially pleased to partner with a renowned AML MDS clinician, Dr. Uwe Platzbecker to initiate the Phase 2 LUCAS Investigator Sponsored Trial for the treatment of anemia in patients with lower risks MDS. Following the promising preliminary data we presented in December in patients with relapsed refractory AML and high risk MDS, we were encouraged to explore whether CA-4948 may also provide benefits in earlier stage MDS patients who are farther away from progression to AML. If this hypothesis bears out it could lead to a potential breakthrough in the AML and MDS field as current erythropoiesis stimulating agents or ESA that target anemia in genetically defined lower risk MDS can be effective, but this effect is often transient, culminating in progression to AML and further disease complication. With its direct, non-myelosuppressive targeting of IRAK4 and its already demonstrated robust durability profile, we believe CA-4948 could potentially offer a safe and transformative disease modifying alternative for patients in early stage or low risk MDS. Patient enrollment in this study is expected to begin in the second quarter of 2021 and is anticipated to enroll up to 84 patients across two cohorts. Cohort A will be an ESA refractory or intolerant patient. Cohort B in ESA naive patients. Patients in both cohorts will receive 300 milligrams of CA-4948 twice daily BID for 21 days, in at least four repeating cycles, lasting 28 days each. The primary endpoint of the study is to evaluate the proportion of patients that develop an erythroid response according to IWG 2018 criteria. Now moving to lymphoma. 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 Waldenstroms and oncogenic mutations. We are currently in the expansion phase, evaluating patients being treated with 300 milligrams of CA-4948 twice daily, after observing clear dose response and tumor reductions at this level during the dose escalation phase of the study. In an oral presentation at Ash last December, we reported expanded clinical data from this study, highlighting durable reductions in tumor burden that were observed in six of seven evaluable patients treated with 300 milligrams twice daily, single agent CA-4948, following a median of four prior lines of therapy. On the basis of these data, we determined 300 milligrams BID to be the optimal dose for further study, as it appears to strike the most favorable balance of sustained anti-cancer activity and tolerability for long-term treatment, which is critical for these extremely sick patients who have already progressed through several failed lines of treatment. To provide some additional context, these data further supported the trend that first came into focus at Ash 2019, where we presented a small but intriguing data set that suggested CA-4948 could establish IRAK4 inhibition as a new mechanism of action, a novel way to treat patients with NHL as it delivers a compelling safety and efficacy profile, particularly at higher dose levels in a monotherapy setting. Throughout 2020, we had two primary goals for this study. First, we wanted to demonstrate proof of concept in a monotherapy setting, establishing IRAK4 inhibition as a new mechanism of action, a novel way to treat patients with NHL by delivering a compelling safety and efficacy profile, particularly at higher dose levels. This would provide an important read through for our anticipated combination study. And second, we sought to verify which of the efficacious dose levels offered the best balance of safety and efficacy. As shown in the data we presented and in our selection of 300 milligrams BID of CA-4948 as the recommended Phase 2 dose, we believe we clearly hit on both of those points. It is important to highlight again, that these are extremely sick patients who have received in median four prior lines of therapy before entering the study, that we have been able to observe any meaningful therapeutic effect in monotherapy. And that those effects are durable over such an extended period of time is enormously encouraging and provided powerful affirmation of our plan to launch accommodation study with a synergistic therapy like the BTK inhibitor ibrutinib. We initiated this combination study earlier this quarter. Part of the Ash presentation also covered early data for two potential biomarkers that may support patient selection and enrichment efforts. And we look forward to providing updated data on both biomarkers at AACR next month. Now let's talk a little bit about why we and key stakeholders in the NHL clinical community find the prospect of IRAK4 BTK inhibitor combination so compelling. BTK inhibitors like ibrutinib are an approved effective oral class of therapies for patients with various lymphatic cancers that work by targeting one of the main activators of NF-kappaB, The BCR pathway. Crucially, however, comprehensive NF-kappaB regulation requires also shutting down medicinal signaling in the TLR pathway, which is primarily, controlled by IRAK4 the target of CA-4948. In short, two pathways the BCR pathway and the TLR pathway are primary and independent oncogenic drivers of NF-kappaB. This regulation of either of these two pathways drives excessive B cell proliferation. BTK inhibition blocks one, IRAK4 inhibition blocks the other. We believe effective dual targeting of both pathways could provide substantially better outcomes than targeting either pathway alone. And while there are several companies with approved BTK inhibitors, there is only one company developing a BTK IRAK4 combination. That company is Curis. We are currently enrolling patients in the part one of the dose escalation component of the trial, which will enroll approximately 18 patients in a three plus three design with CA-4948 doses starting at 200 milligrams BID, and escalating to 300 milligrams BID. And ibrutinib doses appropriate for the patient's respective NHL subtype. The primary endpoints of the first part of the study, our maximum tolerated dose, and determination of the recommended Phase 2 dose. Secondary endpoints are PK and preliminary efficacy. We'll provide updates appropriately as we progress through enrollment, and eventually move on to part two of the study. But 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 and complimentary to the BCR pathway. And that inhibiting IRAK4 may provide increased benefit to the vast population of patients treated with a BTK inhibitor and help mitigate resistance to BTK therapy. That is our vision for NHL. And we look forward to our next opportunity to update you on this program in the fourth quarter of this year. Now we'd like to turn to CI-8993, our first in class monoclonal antibody for the treatment of patients with relapsed or refractory solid tumors. To provide a little back story, we acquired rights to CI-8993 in Q1. We received IND clearance from the FDA in Q2 and we opened our first clinical sites and dosed our first patient in Q3. Everything has moved incredibly quickly. Since then, we've continued to open more clinical sites and enroll more patients. This is a target that we and the clinical community have long been excited about because of the critical role it plays in suppressing T-cell activity when it is activated. Conversely, when this is blocked, or inactivated, it has been shown in preclinical studies to prevent T-cell suppression and thereby reactivate anti-tumor immune function. We also see significant combination potential and, in the future, may explore targeting VISTA in combination with certain synergistic therapies such as PD1, PDL-1or even CTLA-4 inhibitors. As preclinical studies suggest that blocking VISTA significantly improves the efficacy of those checkpoint regulators. Moreover, progress in the development of CAR-T therapies, in the broader immunotherapy space over the last decade have addressed previously limiting on target side effects associated with this pathway blockade, namely, immune mediated toxicity and cytokine release syndrome. We believe CI-8993 is the most advanced anti-VISTA antibody currently in clinical development. The clinical community has already shown a deep excitement and interest in this program. And we believe CI-8993 has the potential to be a game changer in cancer therapy. We look forward to reporting initial safety and efficacy data for this exciting program in the second half of 2021. To wrap up, I want to emphasize how proud I am of the entire team at Curis who in the midst of an ongoing global pandemic have worked tirelessly to ensure we hit every ambitious goal we set for ourselves this year. It is a testament to their efforts that we find ourselves in a vastly different place than we were 12 months ago. And that much closer to bringing our promising therapeutics to the patients, they will serve the most. I'm honored to work with them every day. With that, I'll turn the call over to Bill to review our financial results for the quarter. Bill?