This section highlights FDA-related milestones and regulatory updates for drugs developed by CytomX Therapeutics (CTMX).
Over the past two years, CytomX Therapeutics has reported clinical trial outcomes, regulatory submissions, approvals, and other FDA events for drugs and therapies such as
CX-2051 and CX-801. For definitions of regulatory abbreviations such as NDA, BLA, or PDUFA, see the event status legend.
CX-2051 - FDA Regulatory Timeline and Events
CX-2051 is a drug developed by CytomX Therapeutics for the following indication: A Probody® Antibody Drug Conjugate (ADC).
This drug is under review by the U.S. Food and Drug Administration (FDA).
Below is a timeline of key regulatory milestones for this therapy.
- Drug:
- CX-2051
- Announced Date:
- May 12, 2025
- Indication:
- A Probody® Antibody Drug Conjugate (ADC)
Announcement
CytomX Therapeutics, Inc announced positive interim Phase 1 data for its EpCAM PROBODY® ADC candidate, CX-2051, in advanced, late-line CRC. The data are as of an April 7th 2025 data cutoff from the ongoing CTMX-2051-101 Phase 1 study.
AI Summary
CytomX Therapeutics announced positive interim Phase 1 data for its EpCAM PROBODY® ADC candidate, CX-2051, in advanced, late-line colorectal cancer. The ongoing CTMX-2051-101 study showed promising results at an April 7, 2025 data cutoff. In expansion doses of 7.2, 8.6, and 10 mg/kg Q3W, 18 evaluable patients achieved a 28% confirmed partial response rate by RECIST v1.1. Notably, at the highest dose of 10 mg/kg, 43% of patients responded positively, highlighting impressive anti-tumor activity even in this challenging treatment area.
The trial also reported a median progression-free survival of 5.8 months and a favorable safety profile with no dose limiting toxicities. Based on these encouraging findings, CytomX plans to initiate a Phase 2 study in the first half of 2026 to further explore CX-2051’s potential for patients with advanced colorectal cancer.
Read Announcement- Drug:
- CX-2051
- Announced Date:
- March 6, 2025
- Indication:
- A Probody® Antibody Drug Conjugate (ADC)
Announcement
CytomX Therapeutics, Inc. provided a business update.
AI Summary
CytomX Therapeutics provided an update on its business progress, with a major focus on advancing its lead program, CX-2051. This investigational EpCAM-targeting ADC is being tested in a Phase 1a study for advanced colorectal cancer, and initial clinical data are expected to be presented in the first half of 2025. The company has successfully escalated the dose in patients, reaching levels predicted to be biologically active, which is bringing hope for addressing the unmet need in this patient population.
CEO Sean McCarthy highlighted the promise of CX-2051, noting that the PROBODY® platform could unlock a treatment option for cancers that express EpCAM. Alongside this, CytomX is progressing another candidate, CX-801, with clinical data anticipated in the latter half of 2025. The company also maintained a strong financial position, with cash reserves projected to extend through Q2 2026.
Read Announcement
CX-801 - FDA Regulatory Timeline and Events
CX-801 is a drug developed by CytomX Therapeutics for the following indication: In patients with solid tumors.
This drug is under review by the U.S. Food and Drug Administration (FDA).
Below is a timeline of key regulatory milestones for this therapy.
- Drug:
- CX-801
- Announced Date:
- May 19, 2025
- Indication:
- In patients with solid tumors
Announcement
CytomX Therapeutics, Inc. announced that the first patient has been dosed with CX-801 in combination with KEYTRUDA® (pembrolizumab), Merck's anti-PD-1 therapy, in the ongoing Phase 1 dose escalation study (NCT06462794) evaluating safety and initial clinical activity in patients with metastatic melanoma.
AI Summary
CytomX Therapeutics, Inc. has reached a significant milestone in its efforts to improve treatment for metastatic melanoma. The company announced that the first patient has been dosed with CX-801, a dually masked interferon alpha-2b PROBODY cytokine, used in combination with KEYTRUDA® (pembrolizumab), Merck’s anti-PD-1 therapy. This combination is part of an ongoing Phase 1 dose escalation study (NCT06462794) designed to evaluate both the safety and the initial clinical activity of the new therapy in patients with advanced melanoma.
CX-801 has been specifically engineered to harness the immune-stimulating benefits of interferon alpha-2b, while limiting its toxic side effects by targeting its activity directly to tumors. By combining CX-801 with KEYTRUDA®, researchers hope to address challenges seen in PD-1 refractory melanoma, potentially offering a new therapeutic option where there is a high unmet need. Early study outcomes will be pivotal for guiding future combination immuno-oncology strategies.
Read Announcement- Drug:
- CX-801
- Announced Date:
- September 9, 2024
- Indication:
- In patients with solid tumors
Announcement
CytomX Therapeutics, Inc announced that the first patient has been dosed with CX-801 monotherapy in a Phase 1 study (NCT06462794) in patients with solid tumors..
AI Summary
CytomX Therapeutics has dosed the first patient in a Phase 1 study using CX-801 monotherapy for treating solid tumors. The study, known as NCT06462794, is designed as a dose escalation trial to evaluate the safety and early signs of clinical activity of CX-801, a dually-masked interferon alpha-2b PROBODY® cytokine. This treatment is intended for patients with specific solid tumors such as advanced melanoma, renal cell carcinoma, and head and neck squamous cell carcinoma. Additionally, the study will explore the use of CX-801 in combination with Merck’s KEYTRUDA, an anti-PD-1 therapy. The innovative approach of using the PROBODY platform aims to improve the delivery of this powerful immune-modulating cytokine, potentially reducing the systemic toxicities seen with traditional interferon treatments and broadening its possible benefits in cancer care.
Read Announcement