High concentrations of hydrogen peroxide can inhibit or denature catalase, as supported by classical and kinetic studies demonstrating substrate-induced inactivation at elevated peroxide levels.
The retrieved literature includes foundational kinetic studies (such as papers [1] and [4]) showing that elevated concentrations of hydrogen peroxide lead to the formation of inactive enzyme species and increased inactivation rates (substrate inhibition/denaturation). Therefore, the claim is well supported by the provided evidence.