A Phase 2a, Single-dose, Open-label Study to Evaluate Diagnostic Performance and Safety of Pegsitacianine, an Intraoperative Fluorescence Imaging Agent for the Detection of Cancer, in Patients With Unknown Primary Head and Neck Cancer (ILLUMINATE STUDY)

Inclusion criteria

• ✓. Adults ≥18 years of age
• ✓. Biopsy-confirmed diagnosis, for primary or recurrent disease (or high clinical suspicion in the opinion of the Investigator)
• ✓. Part 1: Stage 1 to 4 HNSCC
• ✓. Part 2: UPC squamous cell carcinoma of the head and neck with metastatic disease to at least a single cervical node, AND no biopsy proven evidence of the primary cancer's location.
• ✓. Acceptable hematologic status (as standard surgery protocol requires, as determined by the Investigator), kidney function and liver function. Elevations of creatinine, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, or total bilirubin \>1.5× the upper limit of normal \[ULN\] must be determined to be not clinically significant by the Investigator and approved by the Medical Monitor.
• ✓. Documented negative serum pregnancy test for women of childbearing potential (i.e., premenopausal women with intact reproductive organs and women \<2 years after menopause)
• ✓. Male patients and female patients of child-bearing potential (i.e., premenopausal women with intact reproductive organs and women \<2 years after menopause) must agree to and comply with using medically acceptable contraception including surgical sterilization (e.g., hysterectomy, bilateral oophorectomy, bilateral tubal ligation), intrauterine device, oral contraceptive, contraceptive patch, long acting injectable contraceptive, partner's vasectomy, double-barrier method (condom or diaphragm plus spermicide or condom plus diaphragm), or abstinence during the trial and for 6 months thereafter
• ✓. Agree to abstain from alcohol consumption from 72 hours before Pegsitacianine administration through completion of Study Day 10 (±48 hours) visit in Part 1 and Part 2.

Exclusion criteria