A Study of HFB200301 as a Single Agent and in Combination With Tislelizumab in Adult Patients With Advanced Solid Tumors

Eligibility Criteria

• * Previously received the following lines of systemic therapy for the advanced/metastatic disease:
• * Gastric cancer: at least 2 lines of therapy
• * Renal cell carcinoma: at least 2 lines of therapy
• * Melanoma:
• * BRAF V600E mutant: must have received at least 2 lines of therapy
• * BRAF V600E wild type: must have received at least 1 line of therapy
• * Sarcoma: at least 1 line of therapy
• * Testicular germ cell tumor: at least 2 lines of therapy
• * Cervical cancer: at least 2 lines of therapy
• * Mesothelioma: at least 2 lines of therapy
• * Non-small cell lung cancer: at least 2 lines of therapy
• * Head and neck squamous cell carcinoma: at least 2 lines of therapy
• * Suitable site to biopsy at pre-treatment and on-treatment
• * Measurable disease as determined by Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 or modified RECIST (mRECIST) for mesothelioma
• * Eastern Cooperative Oncology Group performance status of 0 or 1
• * Systemic anti-cancer therapy within 2 weeks prior to start of study drug or within 4 weeks for immune-oncologic therapy
• * For soft tissue sarcoma and testicular germ cell tumor patients only: prior immune therapy
• * Therapeutic radiation therapy within the past 2 weeks
• * Prior exposure to agents targeting the Tumor Necrosis Factor Receptor type 2 (TNFR2) receptor
• * Active autoimmune disease requiring systemic treatment in the previous 2 years
• * Systemic steroid therapy (\>10 mg/day of prednisone or equivalent) or any immune suppressive therapy ≤ 14 days before first dose
• * Persisting toxicity of ≥Grade 2 (≥Grade 1 for diarrhea) relating to prior anti cancer therapy with the following exceptions:
• * All grades of alopecia are acceptable
• * Endocrine dysfunction on replacement therapy is acceptable
• * Severe or unstable medical condition, including uncontrolled diabetes, coagulopathy, or unstable psychiatric condition
• * Major surgery within 4 weeks of the first dose of study drug
• * History or presence of drug or non-drug induced interstitial lung disease or pneumonitis ≥Grade 2. For combination only: non-small cell lung cancer patients, mesothelioma or patients with significantly impaired pulmonary function or who require supplemental oxygen at baseline must undergo an assessment of pulmonary function at screening
• * History of allergic reactions, immune related reactions, or cytokine release syndrome (CRS) attributed to compounds of similar chemical or biologic composition to monoclonal antibodies or any excipient of HFB200301
• * Using sensitive substrates of major cytochrome P450 (CYP450) enzymes
• * Known active malignancy, with the exception of the specific cancer under investigation in this trial, that required treatment within the previous 2 years
• * For combination only:
• * Prior randomization in a tislelizumab study regardless of the treatment arm, until the primary and key secondary endpoints of the study have read out
• * Hypersensitivity to tislelizumab or any of its excipients.