Neoadjuvant INBRX-106 (Hexavalent OX40 Agonist) in Combination With Pembrolizumab as a Chemotherapy-sparing Regimen for Stage II TNBC (Triple Negative Breast Cancer) Patients

Triple Negative Breast Cancer Clinical Trial

Official title: A Phase 2a, Single-arm, Multi-center, Open-label Study of Neoadjuvant INBRX-106 (Hexavalent OX40 Agonist) in Combination With Pembrolizumab as a Chemotherapy-sparing Regimen for Stage II TNBC Patients

Status Not yet recruiting

Clinical Trial Summary

This is a Phase II trial to assess feasibility of pembrolizumab + INBRX-106 as a chemotherapy-sparing neoadjuvant therapy. One therapeutic arm is being evaluated to provide an informal comparison of pharmacodynamic and clinical effects of concurrent dosing schedule.

Clinical Trial Description

A Simon 2-stage design is implemented to minimize exposure if the treatment regimen is futile. If feasibility is established with responses exceeding futility parameters, study will expand to stage 2. Additional arms may be introduced in a protocol amendment.

Below shows the sample size required using Simon's 2-stage design, 80% power and 5% one-sided significance level:

• Null hypothesis: <5% pCR

• Alternative hypothesis: >35% pCR

• Stage I n (r*): 6 (0)

• Stage I + II total n (r): 12 (2)

• Criteria: Minimax

• Minimum responses to proceed to stage II: 1

Note: r* and r represents the threshold for declaring futility, i.e. greater than r* or r responses would be required to consider ongoing investigation.

The null hypothesis of 5% is based upon the assumption that virtually no subjects would experience pCR if the therapy was not effective. The alternative hypothesis of 35% is based upon the assumption that complete responses in the absence of chemotherapy in approximately one-third of subjects would be clinically meaningful, encouraging further development of the treatment paradigm.

If no responses are observed, a second feasibility run-in may be considered using a biomarker enrichment strategy (such as with the 27-gene IO score).

The arm will be terminated from further development if an unacceptable proportion of patients experience rapid clinical/radiographic progression (defined as progression of disease, or clinical evidence of progression), or other toxicities that interfere with curative-intent therapy, defined as >1/6 evaluable subjects in stage I or >2/12 in stage II, evaluated for each arm. This is a Pocock-type stopping boundary that yields the probability of cross the boundary at most 23% when the rate of dose-limiting toxicity is equal to 10%. ;

Related Conditions & MeSH terms

• Breast Neoplasms
• Triple Negative Breast Cancer
• Triple Negative Breast Neoplasms

• NCT number: NCT06353997
• Study type: Interventional
• Source: Providence Health & Services
• Contact: Nicole Moxon, RN
• Phone: 503-215-1979
• Email: canrsrchstudies@providence.org
• Status: Not yet recruiting
• Phase: Phase 2
• Start date: June 2024
• Completion date: June 2029