A Phase 0 Multicenter Study of the Pharmacodynamic Effects of Intratumoral Microdose Administration of PBA-0111 in Patients With Solid Tumors

Inclusion Criteria: 1\. Ability and willingness to comply with the study's visit and assessment schedule. 2. Male or female ≥ 18 years of age at Visit 1 (Screening). 3. Pathologic diagnosis of HNSCC, STS (see restrictions in Note below), or TNBC (see restrictions in Note below; TNBC defined as estrogen receptor negative \[\<1% positive tumor cells\], progesterone receptor negative \[\<1% positive tumor cells\], and human epidermal growth factor receptor 2 negative \[0 to 1+\]) with a tumor planned for surgical resection. Note: For STS, only the following subtypes are eligible: undifferentiated pleomorphic sarcoma, alveolar soft part sarcoma, synovial sarcoma, cutaneous angiosarcoma, or myxofibrosarcoma. Note: For TNBC, if prior neoadjuvant therapy, evidence of progressive disease, at the discretion of the investigator. 4. Ability and willingness to provide written informed consent. Voluntary written consent must be given before performance of any study related procedure not part of standard medical care, with the understanding that consent may be withdrawn by the patient at any time without prejudice to future medical care. 5. As assessed or confirmed by the surgeon, at least one lesion (primary tumor, recurrent tumor, metastatic tumor, or metastatic lymph node) that is surface accessible for CIVO injection that contains viable minimum tumor tissue volume and characteristics (e.g., based on clinical evaluation, available pre-operative imaging, pre-injection ultrasound imagin…