On August 13, 2025 CytomX Therapeutics, Inc. (Nasdaq: CTMX), a leader in the field of masked, conditionally activated biologics, reported an update on the CX-2051 Phase 1 study to address certain recent social media posts (Press release, CytomX Therapeutics, AUG 13, 2025, View Source [SID1234655194]).

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"Since our initial data disclosure in May 2025, Phase 1 enrollment has been rapid and is substantially complete. We are on track to provide a data update in the first quarter of 2026. Patient safety remains our top priority as we continue to advance CX-2051 for the treatment of CRC," said Sean McCarthy, D.Phil., chief executive officer and chairman of CytomX.

CX-2051 Program Status:

CX-2051 dose expansions at 7.2 mg/kg, 8.6 mg/kg, and 10 mg/kg doses, administered every three weeks (Q3W) have each enrolled approximately 20 patients as planned.
A single Grade 5 treatment-related acute kidney injury occured in a patient with a complex medical history including having a solitary kidney. The Grade 5 event was believed to be secondary to nausea, vomiting and diarrhea. The Company was made aware of the event on July 11, 2025 and promptly reported the event to the FDA on July 18, 2025 in accordance with regulatory requirements.
The CTMX-2051-101 Safety Review Committee convened on July 14, 2025 and supported continued study execution and enrollment.
The CTMX-2051-101 study is ongoing. A Phase 1 data update is expected by Q1 2026.