CytomX Therapeutics Announces Milestone Achievement in Probody® T-Cell Engaging Bispecific (TCB) Collaboration with Astellas

-Achievement of clinical candidate is the first in the multi-target collaboration and triggers a $5 million milestone payment to CytomX-

-CytomX-retained US co-commercialization and economic rights for select programs-

SOUTH SAN FRANCISCO, Calif., Jan. 26, 2023 (GLOBE NEWSWIRE) — CytomX Therapeutics, Inc. (Nasdaq: CTMX), a leader in the field of conditionally activated, localized biologics, today announced that it achieved a clinical candidate milestone under its TCB agreement with Astellas. The clinical candidate is the first Probody® TCB molecule to progress in the collaboration and will trigger a $5 million dollar milestone payment to CytomX. CytomX and Astellas are also collaborating on additional conditionally activated TCB programs with CytomX eligible to receive future preclinical, clinical and commercial milestones. CytomX retains a cost share and co-commercialization option on a select number of targets.

“We are pleased with the achievement of the first Probody® TCB clinical candidate in our collaboration with Astellas and that our discovery and research capabilities in this important modality continue to deliver next-generation, localized drug candidates. We look forward to continuing to partner with Astellas in advancing novel TCBs towards the clinic and potentially making a significant contribution in bringing the power of T-cell engaging therapies to a broader set of patients with cancer,” said Dr. Marcia P. Belvin, Ph.D., senior vice president and head of research at CytomX.

“The progress with Astellas highlights our strategy to create value through a broad, diversified pipeline of wholly-owned and partnered therapeutic programs as well as expanding our research and development efforts in the field of TCBs. T-cell engaging therapies hold tremendous promise; however, the potency of this modality can lead to widespread activation of the immune system and a narrow therapeutic window. Localizing T-cell activity to the tumor microenvironment could result in important breakthroughs for patients, and the Probody® platform has potential to address this challenge,” said Sean McCarthy, D.Phil., chief executive officer and chairman of CytomX Therapeutics.

About CytomX Therapeutics
CytomX is a clinical-stage, oncology-focused biopharmaceutical company dedicated to destroying cancer differently. By pioneering a novel class of conditionally activated biologics, powered by its Probody^® technology platform, CytomX’s goal is to transcend the limits of current cancer treatments. CytomX’s robust and differentiated pipeline comprises seven therapeutic candidates across multiple treatment modalities including antibody-drug conjugates (“ADCs”), T-cell engaging bispecific antibodies (“TCBs”), and immune modulators such as cytokines and checkpoint inhibitors (“CPIs”). CX-2029 is an investigational conditionally activated antibody-drug conjugate (ADC) directed toward CD71 and is being developed in collaboration with AbbVie. CytomX’s clinical pipeline also includes cancer immunotherapeutic candidates against validated targets such as the CTLA-4-targeting Probody therapeutics, BMS-986249 and BMS-986288, partnered with Bristol Myers Squibb, as well as CX-904, a conditionally activated T-cell-engaging bispecific antibody targeting the epidermal growth factor receptor (EGFR) on tumor cells and the CD3 receptor on T cells, which is partnered with Amgen. In addition, CytomX has a diverse preclinical portfolio of wholly-owned assets including CX-801, an interferon alpha-2b Probody cytokine that has broad potential applicability in traditionally immuno-oncology sensitive as well as insensitive (cold) tumors and CX-2051, a conditionally activated ADC directed toward EpCAM, with potential applicability across multiple EpCAM-expressing epithelial cancers. CytomX has also established strategic collaborations with multiple leaders in oncology, including AbbVie, Amgen, Astellas, Bristol Myers Squibb, Regeneron and Moderna. For more information about CytomX and how it is working to make conditionally activated treatments the new standard-of-care in the fight against cancer, visit www.cytomx.com and follow us on LinkedIn and Twitter.

CytomX Therapeutics Forward-Looking Statements
This press release includes forward-looking statements. Such forward-looking statements involve known and unknown risks, uncertainties and other important factors that are difficult to predict, may be beyond our control, and may cause the actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied in such statements, including those related to the future potential of partnerships or collaboration agreements. Accordingly, you should not rely on any of these forward-looking statements, including those relating to the potential benefits, safety and efficacy or progress of CytomX’s or any of its collaborative partners’ product candidates, including CX-2029, BMS-986249, BMS-986288, pacmilimab, CX-904, CX-801, and CX-2051, the potential benefits or applications of CytomX’s Probody platform technology, CytomX’s ability to develop and advance product candidates into and successfully complete clinical trials, including the ongoing and planned clinical trials of CX-2029, BMS-986249, BMS-986288, pacmilimab, and CX-904, and the timing of the commencement of clinical trials, initial and ongoing data availability, investigational new drug applications and other development milestones. Risks and uncertainties that contribute to the uncertain nature of the forward-looking statements include: the unproven nature of CytomX’s novel Probody Platform technology; CytomX’s clinical trial product candidates are in the initial stages of clinical development and its other product candidates are currently in preclinical development, and the process by which preclinical and clinical development could potentially lead to an approved product is long and subject to significant risks and uncertainties, including the risk that the COVID-19 worldwide pandemic may continue to negatively impact the business, research and clinical operations of CytomX or its partners, including the development of preclinical drug candidates due to delays in and disruption of research activities and the development of clinical drug candidates due to delays in or disruption of clinical trials, including impacts on the enrollment of patients in clinical trials or other clinical trial disruptions; the possibility that the results of preclinical research and early clinical trials may not be predictive of future results; the possibility that CytomX’s clinical trials will not be successful; the possibility that current preclinical research may not result in additional product candidates; CytomX’s dependence on the success of CX-2029, BMS-986249, BMS-986288, pacmilimab, CX-904, CX-801, and CX-2051; CytomX’s reliance on third parties for the manufacture of the Company’s product candidates; and possible regulatory developments in the United States and foreign countries. Additional applicable risks and uncertainties include those relating to our preclinical research and development, clinical development, and other risks identified under the heading “Risk Factors” included in CytomX’s Quarterly Report on Form 10-Q filed with the SEC on November 8, 2022. The forward-looking statements contained in this press release are based on information currently available to CytomX and speak only as of the date on which they are made. CytomX does not undertake and specifically disclaims any obligation to update any forward-looking statements, whether as a result of any new information, future events, changed circumstances or otherwise.

Probody is a U.S. registered trademark of CytomX Therapeutics, Inc.

CytomX Contact:
Chris Ogden
SVP, Finance and Accounting
cogden@cytomx.com
317-767-4764

Investor and Media Contact:
Stern Investor Relations
Stephanie Ascher
stephanie.ascher@sternir.com
212-362-1200