Sean McCarthy
Analyst · Barclays
Great. Thank you, Chris, and good afternoon, everyone. Thanks for joining us. It’s a pleasure to be here to provide an update on our progress during the second quarter of 2020. I’ll begin today’s call with a brief overview of our recent achievements, including our presentations at ASCO 2020 and the next steps for our lead clinical programs. I’ll also comment briefly on our preclinical discovery progress, and we’ll then turn the call over to Carlos to review our second quarter financial results. We’ll then open the call up for questions. At CytomX, we are pioneering a novel class of therapeutic antibodies designed to target cancer tissue, allowing for the development of an innovative pipeline of novel cancer therapies. Over the past decade, we have built a strong scientific foundation for our mobile technology, which has the potential to change the way we think about antibody therapeutics. Our technology called the Probody platform is designed to direct an antibody’s anticancer activity towards tumor tissue and away from normal healthy tissue, allowing us to attack new classes of targets that have previously been considered inaccessible to conventional antibody approaches. Our primary strategy is to use our technology to make first-in-class anticancer drugs for the potential treatment of a wide range of cancers by targeting these previously undruggable targets. We’re also utilizing our technology to discover and develop potentially best-in-class immunotherapies. We have four clinical-stage programs advancing towards or already in Phase II clinical studies. These are CX-2029, a Probody drug conjugate targeting CD71 that we are advancing into Phase II studies in multiple tumor types, including head and neck and non-small cell lung cancers. CX-2009, a Probody drug conjugate targeting CD166 that we are advancing into Phase II studies in breast cancer, CX-072, a Probody therapeutic targeting PD-L1 that we are advancing in combination with CX-2009 in triple negative breast cancer; and BMS-986249, an anti-CTLA-4 Probody therapeutic currently in a randomized Phase II study in melanoma, which is being run by our partner, Bristol-Myers Squibb. In parallel with building and advancing our broad clinical pipeline, we have formed many strong partnerships with leading biopharmaceutical companies, including BMS, Amgen, AbbVie and Astellas, all of whom are advancing novel product candidates utilizing our technology. We have integrated research and development capabilities, and our ambition is to ultimately commercialize our products ourselves and with our partners as we build a long-term sustainable values-based organization. I’d like to spend some time laying out the high-level strategy for each of our four clinical assets. And how the data we presented at ASCO 2020 has pointed the way to our Phase II programs as we evaluate the full potential of each product candidate in further detail. Let’s begin with CX-2029, a Probody drug conjugate targeting CD71. CD71 is also known as the transferrin receptor, a protein that is highly expressed on many cancer types, but due to its involvement in iron metabolism has been traditionally thought of as undruggable. We know, in fact, that antibody-drug conjugates targeting CD71 are not developable due to lethal toxicity at low doses in animal models. However, given the high potential of CD71 as a novel anticancer target, we have investigated whether our Probody technology could allow us to achieve therapeutic levels of an anti-CD71 drug conjugate in cancer patients, potentially unlocking this first-in-class approach across a range of different cancer types. Our Phase I results presented at ASCO 2020 show, for the first time that by employing our technology, CD71 can indeed be targeted successfully in patients with advanced cancers. Our dose escalation study achieved therapeutic levels of CX-2029, and objective confirmed single-agent responses were observed in patients with squamous non-small cell lung cancer and with head and neck squamous cell cancer. The principal dose-limiting toxicity seen in this Phase I study was anemia, which was managed with red blood cell transfusions. These promising Phase I results for CX-2029 are particularly important because targeting CD71 is likely the most rigorous tests we have conducted to date to assess our Probody technology. And these results, we believe, underscore the broad potential of our platform. These Phase I data also resulted in CytomX earning a $40 million milestone payment from AbbVie, our partner for this program, which we received in the second quarter. CytomX continues to lead clinical development in this global co-development and commercialization alliance. We expect to initiate Phase II expansion cohorts of CX-2029 at the dose of 3 milligrams per kilogram every three weeks in head and neck squamous cell carcinoma, squamous non-small cell lung cancer, squamous esophageal carcinoma and DLBCL in the second half of 2020, with potential for the first data readouts in late 2021. Turning now to CX-2009, our wholly-owned drug candidate targeting the previously undruggable target CD166. CD166 is widely expressed across multiple tumor types, and we believe has broad potential as a novel anticancer target. However, like CD71, CD166 is present on many normal tissues, ruling it out as a target for conventional therapeutic antibody approaches. To unlock the potential in this novel pathway, we have designed CX-2009 as CD166 targeting Probody conjugated to the well-characterized cytotoxic payload, DM4. Similar to our experience with CX-2029 that we just discussed, our Phase I dose escalation study with CX-2009 in patients with selected advanced solid tumors, achieved therapeutic exposures of the drug candidate, and we observed evidence of single-agent anticancer activity in several tumor types, including breast cancer and ovarian cancer. CX-2009 was generally well tolerated. The principal dose-limiting toxicities were ocular, anticipated and well documented secular of DM4 conjugates and that we intend to manage with ocular prophylaxis in ongoing studies. With Phase 1 now complete for this asset, our program strategy is presently focused on breast cancer. Of note, CD166 expression is high in greater than 80% of hormone receptor positive HER2-negative breast cancer patients; and in approximately 50% of patients with triple-negative breast cancer. In our Phase I study, we observed durable clinical activity in both of these breast cancer populations, despite these patients being very heavily pretreated. Significant unmet medical need remains in breast cancer, and accordingly, we previously announced the initiation of a Phase II expansion study of CX-2009 in hormone receptor positive HER2-negative breast cancer. We didn’t like to pause this study in March 2020 due to the impact of the COVID pandemic. However, our team has used the intervening period resulting from the pandemic to further refine the study with a focus on patient enrollment criteria, including prior treatment regimens. This revised trial will continue to evaluate CX-2009 monotherapy at 7 milligrams per kilogram administered every three weeks, and we aim to enroll at least 40 patients. We expect to reinitiate the study during the second half of 2020. We’re also preparing to initiate Phase II expansion studies of CX-2009 in triple-negative breast cancer, both as monotherapy and in combination with our wholly-owned anti-PD-L1 Probody, CX-072. We have previously reported single-agent activity for CX-072 in triple-negative breast cancer and have also presented our preclinical data that provide experimental rationale for combination treatment of CX-2009 with PD inhibition, consistent with the well-established benefits of combining chemotherapy and checkpoint inhibition. We’re excited to also get this work underway in the second half of this year. These Phase II studies of CX-2009 in hormone receptor positive and triple-negative breast cancers are important next steps in our further evaluation of the potential of this novel first-in-class drug candidate, and we are working towards initial data by the end of 2021. Moving on now to our PD-L 1 inhibitor, CX-072 in further detail. Updated data from our Phase I/II trial of CX-072 from multiple expansion cohorts continued to show durable antitumor activity in patients with IO sensitive tumors, such as triple-negative breast cancer, anal squamous cell carcinoma, cutaneous squamous cell carcinoma and tumors with high mutational burden. This data was presented at ASCO 2020. I’d like to spend a few moments here highlighting the high tumor mutational burden cohort for CX-072, which is illustrative of the unique and potentially differentiated clinical profile of this asset. 14 patients with various advanced tumor types with high TMB were treated with CX-072 at 10 mg per kg. Of 10 efficacy evaluable patients, three confirmed partial responses and one confirmed – one complete response were observed. The partial responses were in colorectal, cutaneous squamous cell carcinoma and neuroendocrine carcinoma and the complete response was in a patient with anal squamous cell carcinoma. CX-072 was well tolerated with only 2% grade 3 or higher immune-related adverse events. These data are particularly of note in view of Merck’s approval in mid-June this year of Keytruda in solid tumors with high TMB. As we now conclude our first clinical explorations with CX-072, which is the first Probody therapeutic to be evaluated in humans, we’re very encouraged that our platform is functioning as designed, and these findings provide rationale for differentiation of CX-072 from other PD inhibitors and support combination strategies with CX-2009 and other anticancer agents. Turning now to another exciting application of our technology in cancer immunotherapy and our work with our partner, Bristol-Myers Squibb, who presented data during the second quarter for 2 anti-CTLA-4 Probody programs, BMS 986249 and BMS 986288, which I will refer to you as BMS 249 and BMS 288, respectively. At ASCO, BMS presented the first clinical data for BMS 249, a Probody version of the anti-CTLA-4 antibody, ipilimumab. This is a novel therapeutic strategy to enhance CTLA-4 exposure in the tumor microenvironment, while potentially sparing systemic toxicity. The trial evaluated BMS 249 as monotherapy or in combination with the anti-PD-1 antibody, nivolumab in patients with advanced cancers with doses ranging from 240 milligrams to 2,400 milligrams of the Probody, which for reference is approximately 3 to 30 mg per kg. Ipilimumab is typically used clinically at doses of 1 to 3 mg per kg. Safety data from the Phase I trial showed that BMS 249 was generally well tolerated as monotherapy and in combination with nivo. The types of treatment-related adverse events were consistent with those seen with the parent molecule ipilimumab. And the incidence of Grade 3 and above adverse events were supportive of the Probody mechanism of action. Based on these Phase I findings, BMS has initiated a randomized cohort expansion, evaluating the tolerability and activity of BMS 249 in combination with nivo versus nivo with or without ipilimumab in metastatic melanoma. The advancement of BMS 249 into this study triggered a milestone payment of $10 million from BMS to CytomX that was received in the second quarter. This is an important study that has the potential to provide additional validation of this novel product candidate. Staying with CTLA-4 for a few moments, also in Q2 at AACR, BMS presented preclinical data for BMS 249 and also BMS 288, which is a Probody of a nonfucosylated version of ipilimumab. BMS 249 and BMS 288 demonstrated equivalent intratumoral pharmacodynamic activity and comparable antitumor activity relative to their parental antibodies. These data also showed that the Probody versions are significantly safer than each underlying antibody, demonstrating highest nonseverely toxic doses in animal models that were fivefold and threefold improved, respectively. These data support the strategy of using our Probody technology to expand therapeutic index for CTLA-4 therapy and are strongly consistent with the clinical experience to date that BMS has reported with BMS 249. The nonfucosylated Probody, BMS 288 is also in the clinic in a Phase I dose escalation study. Before I turn over to Carlos for a review of our financials, I’d like to provide brief updates on three early stage programs at CytomX that are emerging as a potential second wave of product candidates in our pipeline. Let me begin with CX-904, our T-cell bispecific Probody targeting eGFR and CD3, partnered with Amgen. We believe the application of our Probody technology has the potential to enable solid tumor targeting of this modality. Such targeting with unmasked T-cell bispecifics has been very challenging for the field due to narrow or non-existent therapeutic windows. We continue to advance this candidate towards IND-enabling studies and expect to file in late 2021. Turning to CX-2043, our wholly owned EpCAM targeting Probody drug conjugate, CX-2043 was developed utilizing CytomX’ Probody technology and ImmunoGen’s drug conjugate technology and arose from our previous strategic collaboration. We continued to advance this candidate towards IND-enabling studies. Lastly, as part of the strategic collaboration with Astellas that we announced in the first quarter, for which we received an $80 million upfront payment, we have now launched discovery activities surrounding the development and ultimate commercialization of novel T-cell engaging bispecific antibodies in masked form. This is our second alliance in this exciting area of research, and we have high hopes for this Probody format. With that, let me hand the call over to Carlos to review our financial update.