This is a phase 2b, double-blind, placebo-controlled, 4-arm, adaptive-design trial, initially stratified by cisplatin regimen, and then randomized 1:1:1:1. The study will be conducted in subjects receiving ChemoRT for the treatment of squamous cell carcinomas (SCCs) of the oral cavity, oropharynx, hypopharynx, or larynx. The study includes a treatment period of approximately 7 weeks, depending on the subject's prescribed radiation plan, and Week 1 and Week 4 post RT follow-up visits. It also includes a longer follow-up period of approximately 12 months to determine if there is an effect of SCV 07 on the tumor response to ChemoRT.

Inclusion Criteria:

• Willing and able to understand and sign an informed consent form (ICF) for the study approved by the Investigator's local or a central Institutional Review Board (IRB)

• Have recently diagnosed, pathologically confirmed, non-metastatic SCC of the oral cavity, oropharynx, hypopharynx, or larynx that will be treated with ChemoRT as first-line treatment; subjects with a history of surgical management are eligible

• Have a plan to receive a continuous course of conventional external beam irradiation delivered by intensity-modulated radiotherapy (IMRT) as single daily fractions of 2.0 to 2.2 Gy, with a cumulative radiation dose between 50 and 72 Gy. Planned radiation treatment fields must include at least 2 oral sites (buccal mucosa, floor of oral cavity, tongue, or soft palate), with each site receiving ≥ 50 Gy

• Have a plan to receive a standard cisplatin CT regimen administered tri-weekly (80 to 100 mg/m2, on Days 0, 21, and 42) or weekly (30 to 40 mg/m2)

• Have an Eastern Cooperative Oncology Group (ECOG) performance status ≤ 2

• Have adequate hematopoietic, hepatic, and renal function at the screening visit:

  • Hematopoietic function

    • Hemoglobin ≥ 10 g/dL
    • Absolute neutrophil counts (ANC) ≥ 1,500 cells/mm3
    • Platelet count ≥ 100 × 109/L

  • Hepatic function

    • Total bilirubin < 1.5 times the upper-normal limit (ULN)
    • Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) ≤ 2.0 times the ULN

  • Renal function: Serum creatinine concentration ≤ 2 mg/dL; if result is ≥ 1.4 mg/dL and ≤ 2.0 mg/dL, a 24-hour urinary creatinine clearance test must be performed by the site's local laboratory. To be eligible for the study, a subject must demonstrate a 24-hour urinary creatinine clearance ≥ 50 mL/min

• Have a negative serum pregnancy test if a woman is of childbearing potential

• Agree to use medically acceptable methods of birth control during study participation and for 30 days following the last CTM treatment if a woman is of childbearing potential

• Males or females aged 18 years or older.

Exclusion Criteria:

• Tumor of the lips, sinuses, salivary glands, nasopharynx, or unknown primary tumor
• Metastatic disease (M1) Stage IV C
• Prior radiation to the head and neck
• Plan to be treated with cetuximab (Erbitux®)
• Have undergone induction CT
• History of other malignant tumors, excluding non-melanoma skin cancer or curatively excised in situ cervical carcinoma
• Have had a major surgical procedure, other than for HNC, or significant traumatic injury within 4 weeks prior to the initiation of RT; anticipation of need for a major surgical procedure during the study
• Active infectious disease, excluding oral candidiasis
• Have OM at the baseline visit
• Have a diagnosis of autoimmune disease requiring chronic immunosuppression
• Known seropositivity for HIV, HBV, or HCV
• Prior use of SCV 07
• Have used any investigational agent within 30 days of randomization
• Are pregnant or breastfeeding
• Known allergies or intolerance to cisplatin
• Unable to give informed consent or comply with study requirements, including completing the subject diary and QOL instruments
• Have any other condition or therapy that, in the opinion of the Investigator, would make the subject unsuitable for the study or unable to comply with follow-up visits.