The hydrochloride salt of an orally bio-available quinazoline with potential antineoplastic and radiosensitizing activities. Canertinib binds to the intracellular domains of epidermal growth factor receptor tyrosine kinases (ErbB family), irreversibly inhibiting their signal transduction functions and resulting in tumor cell apoptosis and suppression of tumor cell proliferation. This agent also acts as a radiosensitizing agent and displays synergistic activity with other chemotherapeutic agents.