A Phase I Study of the Anti-CEACAM6 Antibody Tinurilimab (BAY 1834942) in Patients with Advanced Solid Tumors.

Background: Tinurilimab is a humanized immunoglobulin G subclass 2 antibody that blocks carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6), an immune checkpoint regulator that is overexpressed in several tumor types.

Objectives: This phase I study evaluated the safety, tolerability, pharmacokinetics, pharmacodynamics, and tumor response profile of tinurilimab in patients with advanced solid tumors with a described expression of CEACAM6.

Patients And Methods: In this first-in-human, dose-escalation and dose-expansion study, tinurilimab was administered as a 1-h intravenous infusion in 21-day cycles at a starting dose of 2.5 mg, with a planned escalation up to 1800 mg. Following observation of treatment toxicity (cytokine release syndrome in one patient and neutropenia in all patients treated at 30 mg), a premedication regimen was initiated that included dexamethasone 8 mg before and after dosing. Thirty patients received treatment across six dosing cohorts (2.5-100 mg with or without dexamethasone).

Results: The maximum tolerated dose was not determined, as the study was terminated due to an unfavorable benefit/risk assessment. All 30 patients (100%) treated with tinurilimab experienced at least one treatment-emergent adverse event of any grade, most commonly fatigue (36.7%), infusion-related reaction (30.0%), and neutropenia (26.7%). The most common grade ≥ 3 treatment-related adverse events were neutropenia (23.3%), followed by febrile neutropenia, cytokine release syndrome, increased hepatic enzymes, decreased lymphocyte count, hypophosphatemia, lactic acidosis, and acute kidney injury (3.3% each). No patients reported an objective response.

Conclusions: Following study termination, the clinical development program for tinurilimab was discontinued permanently.

Clinical Trial Registration: www.

Clinicaltrials: gov , NCT03596372.