This Clinical Trial is an open, randomized, fasted, single-dose, oral administration 2-sequence, 2-period crossover study to assess bioequivalence of lazertinib between two formulations in healthy adult volunteers. The subjects administer 240mg of lazertinib of different formulations on the fasted status on each period and have a wash-out period for 14-21 days between the first and second period.

This clinical trial will be conducted in healthy male volunteers at Seoul National University Hospital (SNUH) Clinical Trial Center.

It is expected to take approximately 32 days from the first dosing of Investigational Product until the final follow-up visit. Subjects will be hospitalized twice for 4 nights and 5 days with 7-14 days of wash-out period, and one visit will be needed for safety evaluation between 14-17 days from the last dosing of the Investigational Product.

Inclusion Criteria:

• Male, over 19 years of age
• Male participants must agree to use an adequate contraception method from the first to the third month after the last dose.
• Participants must have a body mass index (BMI) between 18.5 and 30.0 kg/m2, inclusive(BMI = weight/height2), and body weight not less than 50 kg.
• Subjects without congenital or chronic diseases within the last 3 years and without pathologic symptoms as determined by medical diagnosis.
• Participants must be healthy on the basis of clinical laboratory tests performed at screening.
• Informed of the investigational nature of this study and voluntarily agree to participate in this study.

Exclusion Criteria:

• Clinically significant medical or psychiatric illness.
• Hypotension (SBP ≤ 90 mmHg or DBP ≤ 50 mmHg) or hypertension (SBP ≥ 150 mmHg or DBP ≥ 100 mmHg).
• A marked baseline prolongation of QTc.
• Within 14 days prior to the first administration of investigational product, use of prescription drugs or herbal medication, or within 7 days use of any over-the-counter medications
• Participants who are planning COVID-19 vaccine within 14 days before the first intake of study drug and to the end of the trials.