CytomX Therapeutics (CTMX) investor relations material

Platform overview and technology differentiation

• Probody therapeutic platform enables selective unmasking of biologics in tumor microenvironments, leveraging tumor-specific protease activity to improve therapeutic windows and reduce off-tumor toxicity.

• The platform supports broad partnerships and non-dilutive funding, exemplified by an expanded Regeneron collaboration focused on bispecific immunotherapies, doubling the deal size to $4 billion with significant upfront and milestone payments.

• Masking technology has demonstrated reduced cytokine release syndrome in T-cell engager clinical work and aims to improve tolerability and efficacy in next-generation immunotherapies.

Varseta-M clinical development and data

• Varseta-M, a masked anti-EpCAM ADC, shows unprecedented anti-tumor activity in late-line metastatic colorectal cancer (CRC), with a 32% response rate and 7-month progression-free survival, outperforming current standards.

• The drug demonstrates efficacy across all CRC subtypes, regardless of mutational status or metastasis location, and is positioned as a first-in-class, potentially best-in-class ADC for CRC.

• Safety profile is differentiated by low rates of hematologic toxicity and absence of classic EpCAM toxicities, attributed to a novel linker and payload.

• Dose optimization is ongoing at 8.6 mg/kg and 10 mg/kg, with strategies to further reduce GI toxicity and optimize dosing for pivotal studies.

Expansion strategies and future plans

• Plans include expanding Varseta-M into earlier CRC treatment lines and combinations with bevacizumab and chemotherapy, aiming to replace irinotecan in the treatment paradigm.

• Broader development into other EpCAM-expressing tumors is prioritized, with a validated patient selection assay and a long-term goal of a pan-tumor label.

• CX-801, a dually-masked interferon alfa-2b, is in dose escalation with pembrolizumab for melanoma, showing strong intratumoral immune activation and tolerability.

• Initial clinical data for CX-801 in combination with KEYTRUDA is expected by year-end, targeting post-checkpoint inhibitor melanoma.

• The company is well-funded following recent financing and the Regeneron deal, with a focus on advancing Varseta-M to approval, expanding the pipeline, and building towards commercial stage.