Phase 2a Study to Evaluate Suppression of Methotrexate-induced Mucositis by TK112690

Inclusion Criteria

• •Male and female subjects over 18 years old with a histologically or cytological confirmed diagnosis of locally residual, recurrent or metastatic SCCHN.
• •Subject must have failed at least one courses of non-MTX chemotherapy, or one course of non-MTX chemotherapy and chemo radiation for treating their SCCHN.
• •No prior systemic treatments for cancer (chemotherapy and/or radiotherapy) 4 weeks prior to screening.
• •No other concurrent, active, invasive malignancies.
• •An Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 2.
• •Must have a life expectancy of at least 6 months.
• •History of brain metastases allowed if disease has stabilized or improved after radiation and/or craniotomy.
• •No active angina or uncontrolled arrhythmia.
• •No detectable infection including hepatitis B/C and HIV.
• •Not pregnant or nursing. Women of childbearing potential must have a negative urine pregnancy test at screening and on the day before dosing and must use medically acceptable methods of birth control. Acceptable methods of birth control include oral or transdermal contraceptives, condoms, spermicidal foam, IUD, progestin implant or injection, abstinence, vaginal ring, or sterilization of partner. The reason for non-childbearing potential, such as bilateral tubal ligation, bilateral oophorectomy, hysterectomy, or post-menopausal for ≥ 1 year, must be specified in the patient's medical history file and CRF.
• •Must have adequate organ and immune function as indicated by the following laboratory values:
• •Parameter Laboratory Values Serum creatinine ≤1.5 x ULN Est. creatinine clearance ≥45 mL/min Total bilirubin ≤2.0 mg/dL (≤34.2 μmol/L) AST \& ALT ≤3 x ULN Absolute granulocytes ≥1.5 x 109 cells/L Platelets ≥100,000/µL
• •● Be able to read and understand, and provide a signature or thumb impression on the Informed Consent Form (ICF) before entering the study.