Study to test CX-2009 in Advanced HR-Positive/HER2-Negative Breast Cancer and of CX-2009 as Monotherapy and in Combination with CX-072 in Advanced Triple-Negative Breast Cancer

Phase 1

• Conditions: HR-positive/HER2-negative breast cancerTriple-negative breast cancer; MedDRA version: 20.0Level: LLTClassification code 10027475Term: Metastatic breast cancerSystem Organ Class: 100000004864; Therapeutic area: Diseases [C] - Cancer [C04]

• Registration Number: EUCTR2020-004618-36-ES
• Lead Sponsor: CytomX Therapeutics, Inc.

Brief Summary

Not available

Detailed Description

Not available

Study Timeline

• Study Start: 2021-02-09
• Last Update Posted: 27 May 2024

Recruitment & Eligibility

• Status: ot Recruiting
• Sex: All
• Target Recruitment: 150

Inclusion Criteria

HR-positive/HER2-negative breast cancer
1. Must have inoperable, locally advanced or metastatic HR-positive/HER2-negative breast cancer
2. Histologically confirmed HR-positive/HER2-negative breast cancer based on the most recent analyzed biopsy defined as
3. ER/PgR > 10%
4. HER2 negative: IHC 0 or 1+ or HER2/CEP17 ratio 2.0 and average
HER2 copy number < 4.0 signals/cell by ISH
5. Must have received at least 2 but no more than 4 prior systemic lines of treatment regimens for inoperable, locally advanced, or metastatic breast cancer (not including single-agent hormonal therapy).
6. At least 1 cyclin-dependent kinase inhibitor 4/6 in any setting is
required.
7. 0 to 2 prior cytotoxic chemotherapy in the inoperable, locally
advanced, or metastatic setting (eg, microtubulin-targeted agents,
including taxanes, antimetabolites, anthracyclines, alkylating agents,
topoisomerase 1 or 2 inhibitor)
8. Patients with brain metastases that are = 1 cm, are asymptomatic,
and require treatment may be eligible after discussion with Medical
Monitor.
9. Patients with central nervous system lesions that are equivocal (ie,
may or may not be brain metastases) as assessed by the Investigator
may be enrolled without definitive local treatment.

TNBC
10. Must have inoperable, locally advanced, or metastatic TNBC
11. Histologically confirmed TNBC based on the most recent analyzed biopsy as defined in the protocol.
12. Archival or fresh tumor tissue must have high CD166 expression by
IHC.
13. Must have received at least 1 but no more than 3 prior systemic lines of treatment regimens for inoperable, locally advanced, or metastatic TNBC
14. Prior receipt of a taxane (paclitaxel or docetaxel)-based regimen in
any setting (neoadjuvant, adjuvant, localized, or advanced/metastatic
disease) is required.
15. If a patient has disease progression within 12 months following
completion of adjuvant therapy, the adjuvant therapy will count toward the number of treatments required for eligibility.
16. Patients with known germline BRCA 1 or 2 mutations must have
received a platinum or poly ADP ribose polymerase (PARP) inhibitor.
17. Arm B only: Patients whose tumors test positive for PD-L1 by an
approved test may enroll to Arm B only if they cannot be (re)treated
with a checkpoint inhibitor (CPI) for safety reasons (e.g., underlying
autoimmune disease, prior CPI treatment caused Grade 3 or 4 irAE
requiring permanent discontinuation)
18. Arm C only: For patients who have received prior checkpoint
inhibitors (CPI) therapy: if the CPI was the most recent treatment given prior to enrollment into this study, the patient must not have progressed within 120 days of the first dose of the CPI.
19. Patients must have tumor tissue known to be positive for PD-L1
expression.
20. Patients with brain metastases that are = 1 cm, are asymptomatic, and require treatment may be eligible after discussion with Medical Monitor.
21. Arms B and C: Patients with brain and/or leptomeningeal metastases are eligible if they have received standard-of-care treatment and are determined to be radiologically and clinically stable (ie, 2 scans at least 28 days apart, including the scan obtained during the screening period) and must not require radiation therapy or corticosteroids within 2 weeks prior to C1D1.
22. Patients with central nervous system lesions that are equivocal (ie, may or may not be brain metastases) as assessed by the Investigator may be enrolled without definitive local treatment.
Are the t

Exclusion Criteria

1. History of malignancy that is active within the previous 2 years.
Exceptions include localized cancers that are not related to the current
cancer being treated, that are considered to have been cured, and in the opinion of the Investigator present a low risk for recurrence.
2. Symptomatic or untreated brain and/or leptomeningeal metastases
3. Unresolved prior therapy-related acute toxicity Grade > 1, including
neuropathy. Alopecia and other nonacute toxicities are not exclusionary.
4. Active or chronic corneal disorder, including but not limited to the
following: Fuchs corneal dystrophy (requiring treatment), history of
corneal transplantation, active herpetic keratitis, and active ocular
conditions requiring ongoing treatment/monitoring such as wet agerelated macular degeneration requiring intravitreal injections, active diabetic retinopathy with macular edema, presence of papilledema, and acquired monocular vision.
5. Serious concurrent illness
6. History of allogeneic tissue/solid organ transplant, stem cell
transplant, or bone marrow transplant

Arm C only
7. History of or current active autoimmune diseases, which is not a
sequela of prior immune CPI therapy, including but not limited to
inflammatory bowel diseases, rheumatoid arthritis, autoimmune
thyroiditis, autoimmune hepatitis, autoimmune dermatologic diseases, systemic sclerosis, systemic lupus erythematosus, autoimmune vasculitis, autoimmune neuropathies, labile type 1 insulin-dependent diabetes mellitus, vascular thrombosis associated with antiphospholipid syndrome, myositis, Sjogren's syndrome, Guillain-Barre syndrome, glomerulonephritis, or myasthenia gravis unless otherwise approved by the Medical Monitor
8. History of myocarditis regardless of the cause
9. History of intolerance to prior immune CPI therapy defined as the
need to discontinue treatment due to an immune-related AE
Prior or concomitant therapies
10. Current use of a known sensitive CYP3A substrate or CYP3A
substrate with a narrow therapeutic index (see Protocol Appendix 4)
11. Receipt of systemic anticancer treatment (including investigational
treatment) within 14 days prior to C1D1 for an oral medication or within 21 days prior to C1D1 for an IV medication
12. Arm C only: Immunosuppressive therapy including chronic systemic steroid (= 10 mg daily prednisone equivalents) within 14 days of C1D1. However, patients who require brief courses of steroids (eg, as prophylaxis for IV contrast or for treatment of an allergic reaction) may be eligible with Medical Monitor approval. Inhaled or topical steroids are permitted.
13. History of severe allergic or anaphylactic reactions to previous mAb therapy or known hypersensitivity to any component of Probody therapeutic
14. Prior treatment with maytansinoid-containing drug conjugates (eg, DM4 antibody drug conjugate)
15. Major surgery (requiring general anesthesia) within 3 months prior to dosing. Patients who have undergone major surgery within this time period may be enrolled after consultation with the Medical Monitor.
16. Receipt of live vaccine within 28 days prior to the planned first dose, including but not limited to measles, mumps, rubella, chicken pox/zoster, yellow fever, rabies, Bacillus Calmette-Guérin, and typhoid vaccines. Intranasal influenza vaccines contain live attenuated virus and are therefore prohibited.
17. Current participation in an ongoing clinical study involving treatment with medications, radiation, or surgery within the past 30 days p

Study & Design

• Study Type: Interventional clinical trial of medicinal product
• Study Design: Not specified