A Study of CodaLytic, an Intratumoral Oncolytic Virus, in Patients With Breast Cancer

This study is a Phase 1, open-label, 3+3 dose-escalation, clinical trial to evaluate the safety and preliminary efficacy of CodaLytic in patients with metastatic or otherwise inoperable breast cancer. After providing informed consent, screened participants will undergo baseline safety assessment and imaging. The Investigator will select an accessible lesion for intratumoral injection of CodaLytic (the injected lesion), and a core needle biopsy sample of this lesion will be obtained for eligible participants to be dosed. The Investigator will also select additional lesions for imaging (target lesions); these target lesions will not be injected or biopsied. If possible, another accessible lesion that is not a target lesion will be selected for biopsy to assess abscopal effect. Three (3) eligible participants who meet all study inclusion and no exclusion criteria will be enrolled in each of four (4) escalating-dose cohorts and administered intratumoral CodaLytic. Up to 3 additional participants per cohort may be enrolled. During the dosing period, participants will be assessed for adverse events, serious adverse events, and dose-limiting toxicities. A safety review committee will review the safety data through Day 28 for the participants in Cohort 1 before participants are enrolled in Cohorts 2 and 3 and safety data through Day 28 for the participants in Cohorts 2 and 3 before participants are enrolled in Cohort 4. The safety review committee will also meet on an ad hoc basis to review any unexpected safety concerns. Enrolled participants will be followed for adverse events, serious adverse events, dose-limiting toxicities to assess safety of CodaLytic administration. Biopsy samples of the injected lesion and, if possible, from a noninjected, nontarget lesion will be collected at Week 5. At the end of treatment, imaging will be performed for staging by Response Evaluation Criteria in Solid Tumours (RECIST) 1.1, and biopsy samples will be collected. Repeat disease assessment will be performed 4 to 8 weeks after the Month 3/EOT visit if complete response (CR) or partial response (PR) is observed at that visit or if progressive disease (PD) is seen at that visit and the participant has not begun additional cancer treatment. After the treatment period, participants may enroll in other studies or be managed with other treatment modalities as indicated, but follow-up assessments of Investigator-assessed tumor response and anticancer treatments will be recorded at Months 6 and 12.