Beamion LUNG-3: A Study to Test Whether Zongertinib Helps People With Surgically Removed, Non-small Cell Lung Cancer With HER2 Mutations Compared With Standard Treatment

This study is open to adults 18 years and older who have early-stage non-small cell lung cancer (NSCLC). Their cancer must have a specific change in a gene called HER2. Genes provide the instructions for making proteins, and this change leads to a faulty HER2 protein. People can join if their lung cancer was removed by surgery, and they have already received certain other anti-cancer treatments. The purpose of this study is to find out if a study medicine called zongertinib helps people with this type of cancer live longer without their cancer coming back after surgery, when compared to standard treatment. Zongertinib is being developed to target the faulty HER2 protein, which can cause cancer cells to grow. In this study, participants are assigned by chance to one of two treatment groups, with an equal chance of being in either group. One group takes the study medicine, zongertinib, by mouth once a day for up to 3 years. The other group receives a standard treatment, chosen by their doctor. This standard treatment may be an immunotherapy medicine given by infusion into a vein every 3 or 4 weeks for up to 1 year, or regular check-ups without active study medicine (observation). Participants can be in this study for up to about 11 years. During this time, they visit the study site regularly for check-ups and study-related tests. The frequency of these visits varies depending on their treatment and how long they have been in the study. In addition to visits at the study site, participants in some treatment groups will also have phone calls with the study team every 3 weeks to check on their health between their scheduled visits. Doctors check for any signs of cancer coming back using imaging scans (like CT or MRI scans); these scans are generally done every 3 months for the first 2 years, then every 6 months for the next 3 years, and then yearly. Participants also fill in questionnaires about their overall wellbeing, health and symptoms. Throughout the study, doctors also check participants' health and note any unwanted effects.

Inclusion criteria: 1. Signed and dated written informed consent in accordance with ICH-GCP and local legislation prior to admission to the trial 2. Patients must be ≥18 years old or over the legal age of consent in their country 3. Male or female patients. Women of childbearing potential (WOCBP) must be ready and able to use dual highly effective methods of birth control per ICH M3 (R2) that result in a low failure rate of less than 1% per year when used consistently and correctly. A list of contraception methods meeting these criteria is provided in the patient information and in the study protocol 4. HER2 mutation: Documented Tyrosine kinase domain (TKD) activating Human epidermal growth factor receptor 2 (HER2) mutations 5. Histology and tumor sample: Histologically confirmed diagnosis of primary NSCLC 6. An archival tumor tissue sample must be submitted to the central laboratory after inclusion of the patient to retrospectively confirm the HER2 status 7. Staging: Pretherapeutic classification not exceeding Stage IIIB 8. Performance status and organ function: * Eastern Cooperative Oncology Group (ECOG) score of 0 or 1 * Adequate organ function based on laboratory values Further inclusion criteria apply. Exclusion criteria: 1. Diagnosis of NSCLC with mixed histology/positive neuroendocrine markers (synaptophysin/CD56) 2. Major surgery (major according to the investigator's assessment) performed within 4 weeks prior to randomization 3. Treatment with radiation therapy for primary NSCLC 4. Co-occurring actionable mutation with approved targeted therapy (e.g. Epidermal growth factor receptor (EGFR) or Anaplastic lymphoma kinase (ALK)) 5. Any investigational drug within 5 half-lives of the compound or any of its related material, if known 6. History or presence of * Active or known pre-existing or history of non-infectious interstitial lung disease/pneumonitis * Active infectious disease requiring systemic therapy * Uncontrolled gastrointestinal disorders affecting drug intake/absorption * Previous or concomitant malignancies within the last 3 years, except certain effectively treated cancers * Significant and/or uncontrolled cardiovascular abnormalities, QT interval corrected for heart rate by Fridericia formula (QTcF) \>470 msec, or ejection fraction \<50% Further exclusion criteria apply.