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Phase I

Phase 1/2 Dose-Escalation and Expansion Study of FLX475 Alone and in Combination With Pembrolizumab in Advanced Cancer

  • Study HIC#:2000023915
  • Last Updated:04/28/2022

This clinical trial is a Phase 1/2, open-label, sequential-group, dose-escalation and cohort expansion study to determine the safety and preliminary anti-tumor activity of FLX475 as monotherapy and in combination with pembrolizumab.

The study will be conducted in 2 parts, a dose-escalation phase (Part 1) and a cohort expansion phase (Part 2). In Part 1 of the study, subjects will be enrolled in sequential cohorts treated with successively higher doses of FLX475 as monotherapy or in combination with pembrolizumab. In Part 2 of the study, subjects will be initially enrolled in Stage 1 of parallel expansion cohorts of FLX475 as monotherapy or in combination with pembrolizumab.

  • Start Date04/27/2022
  • End Date05/01/2021

Trial Purpose and Description

Primary Outcome Measures  :

  1. Safety and tolerability of FLX475 as a single agent and in combination with pembrolizumab measured by the incidence of adverse events, including dose-limiting toxicities and maximum tolerated dose [ Time Frame: Approximately 18 weeks ]
  2. Overall response rate in subjects treated with FLX475 as a single agent and in combination with pembrolizumab [ Time Frame: Through study completion (approximately 2 years) ]

Eligibility Criteria

Inclusion Criteria:

  • Documented advanced or metastatic cancer ineligible for standard therapies with one of the following histologies
    • Dose Escalation: non-small cell lung cancer, head and neck squamous cell carcinoma, nasopharyngeal carcinoma, breast cancer, urothelial carcinoma, gastric cancer, colorectal adenocarcinoma, esophageal carcinoma, cervical cancer, ovarian cancer, classical Hodgkin lymphoma
    • Dose Expansion: nasopharyngeal carcinoma, gastric cancer, EBV+ lymphoma, head and neck squamous cell carcinoma, cervical cancer, non-small cell lung cancer, triple-negative breast cancer
  • Eastern Cooperative Oncology Group (ECOG) Performance Status 0-1
  • Evaluable disease at baseline (at least one measurable target lesion by imaging for expansion cohorts)
  • Tumor available for biopsy

Exclusion Criteria:

  • History of allergy or severe hypersensitivity to biologic agents
  • History of Grade 3-4 immune-related adverse events leading to discontinuation of prior immuno-oncology treatment
  • Active autoimmune disease or serious autoimmune disease within past 2 years requiring systemic therapy
  • History of idiopathic pulmonary fibrosis, organizing pneumonia, drug-induced pneumonitis, idiopathic pneumonitis, (non-infectious) pneumonitis that required steroids, or symptoms of active pneumonitis
  • Prior allogeneic hematopoietic stem cell transplant within 5 years, or prior allogeneic organ transplant
  • Active graft-versus-host disease


For more information about this study, contact: