Study of CBX-12 in Subjects With Advanced or Metastatic Refractory Solid Tumors
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ClinicalTrials.gov Identifier: NCT04902872 |
Recruitment Status :
Recruiting
First Posted : May 26, 2021
Last Update Posted : May 13, 2022
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Condition or disease | Intervention/treatment | Phase |
---|---|---|
Solid Tumor, Adult Epithelial Ovarian Cancer Small Cell Lung Carcinoma Breast Cancer Colorectal Cancer Pancreas Cancer Appendix Cancer Non-small Cell Lung Cancer Gastric Cancer Esophagus Cancer Urothelial Carcinoma Sarcoma | Drug: CBX-12 | Phase 1 Phase 2 |
Phase 1 is the dose-escalation portion of the study in which the safety and tolerability of two dosing schedules of CBX-12 will be evaluated. Subjects in Part A will be treated with CBX-12 on a daily x 5 every 3 weeks schedule (treatment in Part A was discontinued in October 2021). Subjects in Phase 1 Part B will be treated with CBX-12 on a daily x 3 every 3 weeks schedule. Subjects in Phase 1 Part C will be treated with CBX-12 once weekly.
For all parts in Phase 1, after all subjects in a cohort have completed treatment through the DLT period or discontinued treatment due to a DLT, the SRC, composed of the Investigators who have enrolled subjects in the current cohort(s), the study Medical Monitor and ad hoc members (e.g., other Investigators, a statistician) as needed, will review all available safety data, including DLTs and all available PK data for that cohort and make dose-level recommendations.
Once the recommended phase 2 dose (RP2D) has been established in both Part B and Part C, Phase 2 expansion cohorts may open.
Study Type : | Interventional (Clinical Trial) |
Estimated Enrollment : | 112 participants |
Allocation: | Non-Randomized |
Intervention Model: | Sequential Assignment |
Intervention Model Description: | Parts B and C will follow a 3 + 3 design, enrolling 3 subjects in each cohort. (De)escalation rules: DLT period for each subject in Phase 1 Part B will be 3 weeks & 4 weeks in Part C (i.e., 1 cycle). If none of the 3 subjects experience a DLT, dose will be escalated to next highest dose level. If 1 of 3 subjects in cohort experiences a DLT, up to 3 additional subjects will be enrolled/treated at same dose. If none of the additional 3 subjects experience a DLT (i.e., only 1 of 6 subjects in cohort has a DLT), dose will be escalated to next highest level. If 2 or more of up to 6 subjects at dose level have DLTs, enrollment to that cohort will stop, dose will be considered above MTD. Dose will be decreased to previous dose level or to a level intermediate to those previously evaluated. MTD will be highest dose evaluated at which ≤ 1 of 6 have a DLT. A minimum of 6 DLT-evaluable subjects will be enrolled to any dose level being evaluated as possible MTD. |
Masking: | None (Open Label) |
Primary Purpose: | Treatment |
Official Title: | A Phase 1/2 Study of CBX-12 in Subjects With Advanced or Metastatic Refractory Solid Tumors |
Actual Study Start Date : | May 3, 2021 |
Estimated Primary Completion Date : | January 2024 |
Estimated Study Completion Date : | April 2024 |

Arm | Intervention/treatment |
---|---|
Experimental: Phase 1 Dose Escalation (Daily Dosing x 3)
CBX-12 administered on a daily x 3, 3 week schedule
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Drug: CBX-12
CBX-12 is an alphalex construct which consists of a low-pH insertion peptide, a self-immolating linker, and exatecan as the pharmacologically active moiety |
Experimental: Phase 1 Dose Escalation (Once Weekly Dosing )
CBX-12 administered once weekly, 4 week schedule
|
Drug: CBX-12
CBX-12 is an alphalex construct which consists of a low-pH insertion peptide, a self-immolating linker, and exatecan as the pharmacologically active moiety |
Experimental: Phase 2 Ovarian Cancer Expansion Cohort
CBX-12 administered on a daily x 5 every 3 weeks or on a daily x 3 every 3 weeks schedule
|
Drug: CBX-12
CBX-12 is an alphalex construct which consists of a low-pH insertion peptide, a self-immolating linker, and exatecan as the pharmacologically active moiety |
Experimental: Phase 2 Small Cell Lung Cancer Expansion Cohort
CBX-12 administered on a daily x 5 every 3 weeks or on a daily x 3 every 3 weeks schedule
|
Drug: CBX-12
CBX-12 is an alphalex construct which consists of a low-pH insertion peptide, a self-immolating linker, and exatecan as the pharmacologically active moiety |
- Phase 1: Incidence of treatment-emergent adverse events (TEAEs) [ Time Frame: Through the end of study, estimated as 6 months ]NCI CTCAE v5.0
- Phase 1: Recommended Phase 2 Dose for Daily x 3 every 3 weeks schedule of CBX-12 [ Time Frame: 15 months ]Safety Review Committee Analysis of Safety and PK Data each schedule in Part B and Part C
- Phase 1: Recommended Phase 2 Dose for Once Weekly schedule of CBX-12 [ Time Frame: 15 months ]Safety Review Committee Analysis of Safety and PK Data
- Phase 2: Overall response rate (ORR) [ Time Frame: Through the end of study, estimated as 6 months ]ORR Based on RECIST v1.1
- Maximum concentration of CBX-12 [ Time Frame: 5 days ]PK Analysis
- Area under the curve from 0-24 hours of CBX-12 [ Time Frame: 5 days ]PK Analysis
- Time to maximum concentration of CBX-12 [ Time Frame: 5 days ]PK Analysis
- Half-life of CBX-12 [ Time Frame: 5 days ]PK Analysis
- Clearance (CL) of CBX-12 [ Time Frame: 5 days ]PK Analysis
- Apparent Volume of Distribution at Steady State (Vss) CBX-12 [ Time Frame: 5 days ]PK Analysis
- Phase 1: ORR [ Time Frame: Through the end of study, estimated as 6 months ]Based on RECIST v1.1
- Duration of Response (DoR) [ Time Frame: Through the end of study, estimated as 6 months ]Based on RECIST v1.1
- Progression-free Survival (PFS) [ Time Frame: Through the end of study, estimated as 6 months ]Based on RECIST v1.1
- Phase 2: Incidence of TEAEs [ Time Frame: Through the end of study, estimated as 6 months ]NCI CTCAE v5.0

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Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Key Inclusion Criteria:
- Subject has a histologically- or cytologically-diagnosed solid tumor which is advanced or metastatic and which has progressed on or following at least one systemic therapy regimen administered for advanced or metastatic disease or for which no approved therapy exists. Subject's prior treatment should include all approved regimens that have demonstrated a survival advantage for the subject's disease, stage, and line of therapy.
- Has measurable disease per RECIST 1.1.
- An adequate tumor sample must be available from core needle biopsies obtained during the Screening Period and following the subject's most recent systemic therapy.
- Agrees to an on-treatment biopsy preferably of the same lesion from which the pre-CBX-12 treatment sample was obtained as long as the Investigator determines such biopsy can be performed with acceptable safety.
Exclusion Criteria:
- Cytotoxic chemotherapy, biologic agent, investigational agent, or radiation therapy less than or equal to 3 weeks prior to the first dose of CBX-12. The interval may be reduced to 2 weeks for bone only radiation therapy or investigational agents not expected to be associated with adverse events (AEs) after 2 weeks of last administration, with Medical Monitor approval.
- Small-molecule kinase inhibitors or hormonal agents less than or equal to 14 days prior to the first dose of CBX-12.
- Subjects who are currently receiving any other anti cancer or investigational agent(s).
- Clinically significant intercurrent disease.
- Subjects with primary central nervous system (CNS) tumors or clinically active CNS metastases or carcinomatous meningitis. Subjects with stable brain metastasis may be enrolled with Medical Monitor approval.

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT04902872
Contact: Project Manager | 860-501-3027 | clinicalstudies@cybrexa.com |
United States, Connecticut | |
Yale Cancer Center | Recruiting |
New Haven, Connecticut, United States, 06511 | |
Contact: Ingrid Palma 203-833-1034 ingrid.palma@yale.edu | |
Principal Investigator: Joseph Paul Eder, MD | |
United States, Texas | |
NEXT Oncology | Recruiting |
Austin, Texas, United States, 78758 | |
Contact: Glenda Chambers 210-580-9520 gchambers@nextoncology.com | |
Contact: Nicole Klein 737-618-5210 nklein@nextoncology.com | |
Principal Investigator: Andrae L Vandross, MD | |
MD Anderson Cancer Center | Recruiting |
Houston, Texas, United States, 77030 | |
Contact: Krystle Luna 713-302-9904 kaluna@mdanderson.org | |
Principal Investigator: Funda Meric-Bernstam, MD | |
NEXT Oncology | Recruiting |
San Antonio, Texas, United States, 78229 | |
Contact: Cynthia De Leon 210-580-9521 cdeleon@nextoncology.com | |
Principal Investigator: Anthony Tolcher, MD |
Study Director: | Chief Medical Officer | Cybrexa Therapeutics |
Responsible Party: | Cybrexa Therapeutics |
ClinicalTrials.gov Identifier: | NCT04902872 |
Other Study ID Numbers: |
CBX-12-101 |
First Posted: | May 26, 2021 Key Record Dates |
Last Update Posted: | May 13, 2022 |
Last Verified: | May 2022 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | No |
Studies a U.S. FDA-regulated Drug Product: | Yes |
Studies a U.S. FDA-regulated Device Product: | No |
SCLC small cell lung cancer ovarian breast appendix |
colorectal pancreatic NSCLC Sarcoma |
Carcinoma Sarcoma Carcinoma, Ovarian Epithelial Pancreatic Neoplasms Small Cell Lung Carcinoma Esophageal Neoplasms Appendiceal Neoplasms Neoplasms, Glandular and Epithelial Neoplasms by Histologic Type Neoplasms Lung Neoplasms Respiratory Tract Neoplasms Thoracic Neoplasms Neoplasms by Site Lung Diseases |
Respiratory Tract Diseases Carcinoma, Bronchogenic Bronchial Neoplasms Intestinal Neoplasms Gastrointestinal Neoplasms Digestive System Neoplasms Digestive System Diseases Gastrointestinal Diseases Intestinal Diseases Ovarian Neoplasms Endocrine Gland Neoplasms Ovarian Diseases Adnexal Diseases Genital Neoplasms, Female Urogenital Neoplasms |