CytomX Therapeutics Advances Phase 1 Study with CX-801 for Metastatic Melanoma.

CytomX Therapeutics has begun a new phase in its clinical trial for metastatic melanoma, administering the first dose of CX-801 in combination with Merck's KEYTRUDA. This follows successful initial dosing stages and allows for further evaluation of CX-801's clinical impact. Analysts forecast an average target price of $4.88, with a high estimate of $6.00 and a low estimate of $3.50, indicating an upside of 140.15% from the current price of $2.03.

CytomX Therapeutics, Inc. (Nasdaq: CTMX), a leading developer of masked, conditionally activated biologics, has announced the dosing of the first patient with CX-801 in combination with Merck's KEYTRUDA in an ongoing Phase 1 study for metastatic melanoma patients. This marks a significant milestone in CytomX's clinical development pipeline and follows successful initial dosing stages for CX-801 monotherapy [1].

CX-801 is a masked interferon alpha-2b PROBODY® cytokine designed to target tumors while reducing systemic toxicities. The combination trial, which has been initiated following the successful clearance of three CX-801 monotherapy dose escalation cohorts, aims to address the high unmet need in patients with PD-1 refractory melanoma. While interferon alpha-2b has proven anti-cancer activity, its use has been limited due to poor tolerability. CytomX's conditional activation technology seeks to solve this challenge by localizing interferon activity to the tumor microenvironment while minimizing systemic exposure [2].

The trial focuses on PD-1 refractory melanoma, a patient population with limited treatment options after progression on initial immunotherapy. If successful, this combination could provide a new option for patients who currently have few alternatives after failing standard checkpoint inhibitor therapy. Analysts forecast an average target price of $4.88, with a high estimate of $6.00 and a low estimate of $3.50, indicating an upside of 140.15% from the current price of $2.03 [2].

Initial Phase 1a translational and biomarker data are expected in the second half of 2025. This will provide the first signal of whether this approach can generate meaningful clinical activity while maintaining an acceptable safety profile. The combination of CX-801 and KEYTRUDA could potentially address the challenge of primary or acquired resistance to PD-1 inhibition that affects many melanoma patients.

CytomX's progression to testing CX-801+KEYTRUDA combination marks a positive advancement addressing unmet needs in melanoma treatment. The company's platform technology for conditional activation represents a differentiated approach in the competitive immuno-oncology landscape.

References:
[1] https://www.biospace.com/press-releases/cytomx-therapeutics-announces-first-patient-dosed-in-combination-arm-of-phase-1-study-of-cx-801-plus-keytruda-pembrolizumab-in-patients-with-metastatic-melanoma
[2] https://www.stocktitan.net/news/CTMX/cytom-x-therapeutics-announces-first-patient-dosed-in-combination-s37d0cyl8o74.html