CytomX Therapeutics, Inc. 2026 Q2 Earnings Call

Good afternoon. Thank you for joining us. Before we begin, I would like to remind everyone that during this call, we'll be making forward-looking statements. Because forward-looking statements relate to the future, they're subject to inherent uncertainties and risks that are difficult to predict, and many of which are outside of our control. Important risks and uncertainties are set forth in our most recent public filings with the SEC at sec.gov. We undertake no obligation to update any forward-looking statements, whether as a result of new information, future developments, or otherwise. Earlier this afternoon, we issued a press release that includes a summary of our second quarter 2026 financial results and highlights recent progress at CytomX. We encourage everyone to read today's press release and the associated materials which have been filed with the SEC.

The press release, recording of this call, and our SEC filings can be found under the Investors and News section of our website. With me on the call today is Dr. Sean McCarthy, CytomX's Chief Executive Officer and Chairman. Sean will provide an update on our pipeline and company progress before I cover the financials for the quarter. We will then conclude with a Q&A session. With that, I'll turn the call over to Sean.

Thanks, Chris. Good afternoon, everyone. We're pleased to be here today to provide an update on our second quarter developments and what continues to be a highly productive year for CytomX. Our major focus continues to be Varseta-M, our first-in-class EpCAM targeting antibody drug conjugate, which to our knowledge is the only EpCAM-directed ADC in clinical development. We are aggressively developing Varseta-M in metastatic colorectal cancer, which I will refer to as CRC. The unmet need in CRC is very high and, in fact, projected to grow due to increased incidence in younger patients on a global basis. We view Varseta-M as a highly innovative drug candidate for the treatment of CRC and potentially the best-in-class ADC based on our clinical data reported to date.

The Varseta-M development program is broadening rapidly, and we see significant value creation potential across our key priorities, which include, first, advancing Varseta-M toward a registrational study and potential approval as a monotherapy in late-line CRC. Second, developing Varseta-M in combinations to expand into earlier-line CRC with the vision to ultimately replace chemotherapy. Third, exploring Varseta-M as a pan-tumor therapy across multiple EpCAM-expressing cancers. In terms of our operational progress this quarter, I'll start with Varseta-M monotherapy development in late-line CRC. We have enrolled 113 patients into the overall Varseta-M phase I monotherapy study across dose escalation, expansion, and optimization. Enrollment in dose optimization was completed in April, with a total of 40 patients enrolled across the 8.6 and 10 milligram per kilogram doses utilizing adjusted ideal body weight dosing.

We remain on track to report by the end of 2026 a phase I data update for Varseta-M across the entire ongoing phase I trial, with a key focus on the data that underpins monotherapy dose selection and the go-forward development strategy for our first registrational study that we aim to initiate in the first half of 2027. We continue to see monotherapy registrational strategies in either the third or fourth line, depending upon emerging data, as compelling opportunities. We look forward to communicating our strategy later this year. In addition to monotherapy development, we are aggressively advancing Varseta-M in combinations to enable earlier-line CRC therapy. We have made significant progress this quarter. The first combination we're exploring in an ongoing phase I cohort is with bevacizumab, a foundational component of current standard of care in CRC across early and late lines of treatment.

We are exploring Q2-week and Q4-week schedules to align with the clinical schedule of bevacizumab. We continue to enroll late-line patients. We expect to focus on earlier-line patients once we have selected a go-forward dose and schedule. We anticipate reporting initial clinical data in the first half of 2027. Our second combination study that we plan to initiate in Q4 will be a new phase I/II trial initially evaluating escalating doses of Varseta-M in combination with bevacizumab, 5-fluorouracil, and leucovorin in 2nd-line CRC patients. This study is central to our goal of replacing irinotecan with Varseta-M in earlier-line CRC. I'd like to emphasize here that our work to date with Varseta-M has been conducted entirely in late-line unselected CRC patients.

We've made terrific progress. We view Varseta-M as a treatment for all patients with late-line CRC, including patients with liver mets, KRAS mutations, and other clinically meaningful characteristics that in other settings are used to differentiate patients and their treatment options. We think this pan-CRC potential makes Varseta-M stand out from other treatment options. We look forward to building on our promising start by bringing Varseta-M forward as a potential frontline treatment option, ultimately replacing chemotherapy. Now, moving to the development of Varseta-M outside of CRC. We're very excited today to announce that we are initiating phase I expansion cohorts in additional gastrointestinal cancers. Initially, we are expanding into gastric and gastroesophageal junction cancer, pancreatic ductal adenocarcinoma, and biliary tract cancer. These are all EpCAM-positive tumor types. In each case, we see significant unmet need that Varseta-M could potentially address.

We prioritize these tumor types based on a number of criteria, including their known responsiveness to topoisomerase I inhibition and our own Varseta-M preclinical data. We believe these indications could offer compelling regulatory opportunities. Our initial plan is to enroll approximately 20 patients per tumor type to assess Varseta-M's antitumor activity and safety before assessing next steps and potential later-phase development options. As a reminder, in colorectal cancer, we are enrolling an unselected patient population due to the uniformly high expression of EpCAM in this cancer type. For our newly selected GI expansion indications, we think patient selection is advisable in certain cases in order to enrich the patient population while we continue to learn about the relationship between target level and antitumor activity. For pancreatic and biliary tract cancer, we expect to screen patients for EpCAM expression.

For gastric and gastroesophageal junction cancer, like CRC, we expect to enroll an unselected patient population given the high percentage of patients expected to have EpCAM-expressing tumors. Overall, we believe the successful execution of these expansion cohorts could further position Varseta-M as a pan GI ADC, providing additional development opportunities across multiple lines of therapy. To summarize, we are very pleased with the continued progress with Varseta-M, as this really exciting program deepens and broadens toward our first registrational study to earlier lines of therapy and into other GI cancers. We look forward to providing a further update by the end of the year. Now turning to CX-801, our masked interferon alfa-2b program being evaluated in checkpoint refractory melanoma.

We see CX-801 as a new and exciting opportunity to reprogram the immune responsiveness of solid tumors, and we continue to be pleased with the progress of the ongoing phase I study, both as monotherapy and in combination with KEYTRUDA. Starting with monotherapy, we've reached the fourth dose in dose escalation, and to date, CX-801 monotherapy has been generally well-tolerated, including at dose levels exceeding those achieved with commercially available unmasked interferon alfa-2b. Initial biomarker data for CX-801 monotherapy presented previously have reinforced our mechanism of action hypothesis for CX-801 in combination with KEYTRUDA. We continue to make solid progress in the phase I combination study and have now successfully cleared the third dose level and enrollment is ongoing. We look forward to sharing initial clinical data from the phase I study in melanoma in the first half of 2027.

Before I turn the call to Chris to walk through financials, I'd like to highlight our continued additional progress across the organization. During Q2, we announced a major expansion of our collaboration with Regeneron, focused on next-generation masked bispecific immunotherapies. This is the result of our continued strong scientific momentum and represents validation of CytomX's expertise in conditional activation, masking technologies, and protease biology. We've also been very pleased recently to have strengthened the organization through key additions to the Board and Executive Team as we prepare CytomX for the coming phase of growth and development. In May, we were delighted to welcome Mamata Gokhale as our Senior Vice President of Regulatory Affairs. Earlier this week, we announced the appointment of Alejandra Carvajal as our new Chief Legal Officer.

Additionally, as we approach late-phase development for Varseta-M in CRC, we are thrilled to have welcomed Dr. Charles Fuchs to our board of directors. Charlie's a highly accomplished oncology leader, most recently serving as Chief Medical Officer of Tubulis. Prior to that, he led Global Oncology Development at Roche Genentech after transitioning to industry from a long and distinguished career in academia as a global leader in gastrointestinal cancer. Welcome, everyone to the CytomX team. With that, I'll now transition the call over to Chris.

Thank you, Sean. As Sean highlighted, we are making important progress across the increasingly broad Varseta-M development plan, with capital allocated to unlocking multiple layers of value creation over the near and long term. With our current balance sheet, we project cash runway to at least the second half of 2028, which positions us to advance Varseta into its first potential registrational study, pursue combination development to bring Varseta-M into earlier line CRC, and invest in the broader potential of Varseta in multiple EpCAM expressing indications. With that, I'm going to walk through our second quarter financial results. As of June 30th, 2026, we ended the quarter with $330.3 million in cash equivalents, and investments versus $346.7 million in cash as of March 31st, 2026.