Zongertinib

12.1 Mechanism of Action Zongertinib is a kinase inhibitor of human epidermal growth factor receptor 2 (HER2). In vitro, zongertinib inhibited phosphorylation of HER2, downstream signaling of HER2 (phosphorylation of ERK), and proliferation of lung cancer cells harboring HER2 tyrosine kinase domain activating mutations. In vivo, zongertinib demonstrated anti-tumor activity in mouse xenograft models of NSCLC harboring HER2 tyrosine kinase domain activating mutations.

1 INDICATIONS AND USAGE HERNEXEOS is indicated for the treatment of adult patients with unresectable or metastatic non-squamous non-small cell lung cancer (NSCLC) whose tumors have HER2 (ERBB2) tyrosine kinase domain activating mutations, as detected by an FDA-approved test, and who have received prior systemic therapy [see Dosage and Administration (2.1) ] . This indication is approved under accelerated approval based on objective response rate and duration of response [see Clinical Studies (14) ] . Continued approval for this indication may be contingent upon verification and description of clinical benefit in a confirmatory trial. HERNEXEOS is a kinase inhibitor indicated for the treatment of adult patients with unresectable or metastatic non-squamous non-small cell lung cancer (NSCLC) whose tumors have HER2 (ERBB2) tyrosine kinase domain activating mutations, as detected by an FDA-approved test, and who have received prior systemic therapy. ( 1 ) This indication is approved under accelerated approval based on objective response rate and duration of response. Continued approval for this indication may be contingent upon verification and description of clinical benefit in a confirmatory trial. ( 1 )

2 DOSAGE AND ADMINISTRATION Select patients for treatment with HERNEXEOS based on the presence of HER2 (ERBB2) tyrosine kinase domain activating mutations. ( 2.1 ) The recommended dosage of HERNEXEOS is based on body weight: ( 2.2 ) < 90 kg: 120 mg ( 2.2 ) ≥ 90 kg: 180 mg ( 2.2 ) Take HERNEXEOS orally once daily with or without food until disease progression or unacceptable toxicity. ( 2.2 ) 2.1 Patient Selection Select patients for treatment of unresectable or metastatic NSCLC based on the presence of HER2 (ERBB2) tyrosine kinase domain activating mutations in tumor specimens [see Clinical Studies (14) ] . Information on FDA-approved tests for HER2 (ERBB2) tyrosine kinase domain activating mutations is available at: http://www.fda.gov/CompanionDiagnostics. 2.2 Recommended Dosage and Administration The recommended dosage of HERNEXEOS is based on body weight: < 90 kg: 120 mg ≥ 90 kg: 180 mg Take HERNEXEOS orally once daily with or without food until disease progression or unacceptable toxicity. Swallow HERNEXEOS tablets whole with water. Do not split, crush, or chew tablets. Missed Dose If a dose is missed within 12 hours, take the dose. If a dose is missed by more than 12 hours, skip the missed dose and take the next scheduled dose. Vomited Dose If a dose is vomited, do not take an additional dose. Take the next dose at the regularly scheduled time. 2.3 Dosage Modifications for Adverse Reactions The recommended dose reductions for adverse reactions are presented in Table 1. Table 1 Recommended HERNEXEOS Dose Reductions for Adverse Reactions Current HERNEXEOS Dose First Reduction Second Reduction 180 mg 120 mg 60 mg 120 mg 60 mg Permanently discontinue Permanently discontinue HERNEXEOS in patients who are unable to tolerate 60 mg once daily. The recommended dosage modifications for adverse reactions are presented in Table 2. Table 2 Recommended HERNEXEOS Dosage Modifications for Adverse Reactions Adverse Reaction Severity Dosage Modification ALT = alanine aminotransferase; AST = aspartate aminotransferase; CTCAE = Common Terminology Criteria for Adverse Events; ULN = upper limit of normal Hepatotoxicity [see Warnings and Precautions (5.1) ] Grade 3 or 4 ALT and/or AST without increased total bilirubin Interrupt HERNEXEOS until recovered to ≤ Grade 1 or baseline. Resume HERNEXEOS at reduced dose level. Grade 3 total bilirubin Interrupt HERNEXEOS until recovered to ≤ Grade 1 or baseline. Resume HERNEXEOS at reduced dose level. Grade 4 total bilirubin Permanently discontinue HERNEXEOS. ALT or AST ≥ 3× ULN with total bilirubin ≥ 2× ULN Permanently discontinue HERNEXEOS. Left Ventricular Dysfunction [see Warnings and Precautions (5.2) ] LVEF 40 to 50% and decrease from baseline of 10 to 19% Interrupt HERNEXEOS until recovered to ≤ Grade 1 or within 10% from baseline. If recovered to ≤ Grade 1 in ≤ 4 weeks, resume HERNEXEOS at the same dose level. If not recovered to ≤ Grade 1 within 4 weeks, permanently discontinue HERNEXEOS. LVEF 20 to 39% or ≥ 20% decrease from baseline Interrupt HERNEXEOS until recovered to ≤ Grade 1 or within 10% from baseline. If recovered to ≤ Grade 1 in ≤ 4 weeks, resume HERNEXEOS at the reduced dose level. If not recovered to ≤ Grade 1 within 4 weeks, permanently discontinue HERNEXEOS. Symptomatic Congestive Heart Failure Permanently discontinue HERNEXEOS. Interstitial Lung Disease/Pneumonitis [see Warnings and Precautions (5.3) ] Grade 2 Withhold HERNEXEOS until resolution. Resume HERNEXEOS at reduced dose level. Permanently discontinue HERNEXEOS for recurrent ILD/pneumonitis. Grade 3 or Grade 4 Permanently discontinue HERNEXEOS. Diarrhea [see Adverse Reactions (6.1) ] Grade 2 Maintain HERNEXEOS dose. Initiate anti-diarrheal treatment. Grade 2 lasting ≥ 2 days despite anti-diarrheal treatment Interrupt HERNEXEOS until recovered to ≤ Grade 1. Resume HERNEXEOS at reduced dose level. Grade 3 or Grade 4 Interrupt HERNEXEOS until recovered to ≤ Grade 1. Resume HERNEXEOS at reduced dose level. Permanently discontinue HERNEXEOS if diarrhea does not resolve to ≤ Grade 1 within 14 days, despite optimal supportive care (including anti-diarrheal treatment) and treatment interruption. Other Adverse Reactions [see Adverse Reactions (6.1) ] Grade 3 Interrupt HERNEXEOS until recovered to ≤ Grade 1 or baseline. Resume HERNEXEOS at reduced dose level. Grade 4 Permanently discontinue HERNEXEOS. 2.4 Dosage Modifications for Drug Interactions Strong CYP3A Inducers Avoid concomitant use of strong CYP3A inducers with HERNEXEOS . If concomitant use cannot be avoided, increase the HERNEXEOS dose based on body weight [see Drug Interactions (7.1) ] : < 90 kg: from 120 mg to 240 mg ≥ 90 kg: from 180 mg to 360 mg After discontinuing a CYP3A inducer, resume the HERNEXEOS dose (7 to 14 days after discontinuing the CYP3A inducer) that was taken prior to initiating the CYP3A inducer.

6 ADVERSE REACTIONS The following adverse reactions are discussed in greater detail in other sections of the labeling: Hepatotoxicity [see Warnings and Precautions (5.1) ] Left Ventricular Dysfunction [see Warnings and Precautions (5.2) ] Interstitial Lung Disease/Pneumonitis [see Warnings and Precautions (5.3) ] Most common adverse reactions (≥ 20%) are diarrhea, hepatotoxicity, rash, fatigue, and nausea. ( 6.1 ) The most common (≥ 2%) Grade 3 or 4 laboratory abnormalities were decreased lymphocytes, increased alanine aminotransferase, increased aspartate aminotransferase, decreased potassium, and increased gamma glutamyl transferase. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Boehringer Ingelheim Pharmaceuticals, Inc. at 1-800-542-6257 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice. The pooled safety population described in WARNINGS AND PRECAUTIONS reflects exposure to HERNEXEOS in 260 patients with unresectable or metastatic non-squamous NSCLC with HER2 (ERBB2) mutations who received HERNEXEOS as a single agent at 120 mg orally once daily until disease progression or unacceptable toxicity in Beamion LUNG-1 [see Clinical Studies (14) ] . Among 260 patients who received HERNEXEOS, 58% of patients were exposed for 6 months or longer and 13% were exposed for greater than one year. In this pooled safety population, the most common (> 20%) adverse reactions were diarrhea (53%), hepatotoxicity (27%), rash (27%), fatigue (22%), and nausea (21%). The most common (≥ 2%) Grade 3 or 4 laboratory abnormalities were decreased lymphocytes (9%), increased alanine aminotransferase (5%), increased aspartate aminotransferase (4.3%), decreased potassium (2.7%), and increased gamma glutamyl transferase (2.7%). Beamion LUNG-1 The safety of HERNEXEOS was evaluated in Beamion LUNG-1 in 105 patients with previously treated unresectable or metastatic non-squamous NSCLC with HER2 tyrosine kinase domain (TKD) mutations; all patients had received prior platinum-based chemotherapy, and 34 patients had received prior treatment with a HER2-directed antibody drug conjugate (ADC) [see Clinical Studies (14) ] . Patients received HERNEXEOS as a single agent at 120 mg once daily until disease progression or unacceptable toxicity. Among patients who received HERNEXEOS, 72% were exposed for 6 months or longer and 30% were exposed for greater than one year. The median age of patients who received HERNEXEOS was 61 years (range 30 to 85), 69% were female, 40% White, 49% Asian, and 0% Black or African American; 11% had unknown race data; 1.9% were of Hispanic or Latino ethnicity; and 33% had an Eastern Cooperative Oncology Group (ECOG) performance score of 0 and 67% had an ECOG performance score of 1. Serious adverse reactions occurred in 34% of patients receiving HERNEXEOS. Serious adverse reactions in ≥ 2% of patients included dyspnea (4.8%), pulmonary embolism (4.8%), hepatotoxicity (2.9%), and pneumonia (2.9%). Fatal adverse reactions occurred in 1% of patients who received HERNEXEOS, due to pneumonia. Permanent discontinuation of HERNEXEOS due to an adverse reaction occurred in 2.9% of patients. Adverse reactions which resulted in permanent discontinuation of HERNEXEOS were hepatotoxicity, increased blood alkaline phosphatase, dyspnea, increased gamma-glutamyl transferase, hemoptysis, and pyrexia. Dosage interruption of HERNEXEOS due to an adverse reaction occurred in 28% of patients. Adverse reactions which required dosage interruption in ≥ 2% of patients were hepatotoxicity, decreased ejection fraction, and rash. Dose reductions of HERNEXEOS due to adverse reactions occurred in 7% of patients. Adverse reactions which required dose reductions in ≥ 1% of patients were hepatotoxicity, decreased ejection fraction, increased blood creatinine phosphokinase, increased gamma-glutamyl transferase, and decreased neutrophil count. Tables 3 and 4 summarize adverse reactions and laboratory abnormalities observed in Beamion LUNG-1. Table 3 Adverse Reactions (≥ 15%) in Patients with Non-Squamous NSCLC with HER2 TKD Mutations Who Received HERNEXEOS in Beamion LUNG-1 Adverse Reaction HERNEXEOS N = 105 All Grades 1 % Grade 3 or 4 % Events were graded using NCI CTCAE version 5.0. 1 No Grade 4 or Grade 5 adverse reactions occurred. *Grouped term. Gastrointestinal Disorders Diarrhea* 52 1 Nausea 24 1 Vomiting 15 1.9 Skin and Subcutaneous Tissue Disorders Rash* 32 1 Nail disorders* 19 0 General Disorders Fatigue* 25 0 Respiratory, Thoracic and Mediastinal Disorders Cough* 24 0 Dyspnea* 15 6 Musculoskeletal and Connective Tissue Disorders Musculoskeletal pain* 24 1.9 Infections and Infestations Upper respiratory tract infections* 21 0 Clinically rel

7 DRUG INTERACTIONS Strong CYP3A Inducers : Avoid concomitant use with strong CYP3A inducers. If concomitant use cannot be avoided, increase HERNEXEOS dose. ( 7.1 ) BCRP Substrates : Avoid concomitant use with certain BCRP substrates where minimal concentration increase may lead to serious adverse reactions and consider alternative therapies. If concomitant use cannot be avoided, monitor patients closely for adverse reactions and follow recommendations provided in the BCRP substrate approved product labeling. For other BCRP substrates, monitor for increased adverse reactions and adjust the dosages of those substrates as clinically appropriate. ( 7.2 ) 7.1 Effects of Other Drugs on HERNEXEOS Avoid concomitant use of HERNEXEOS with strong CYP3A inducers. If concomitant use cannot be avoided, increase HERNEXEOS dose as recommended [see Dosage and Administration (2.4) ]. Zongertinib is a CYP3A substrate. Strong CYP3A4 inducers decrease zongertinib exposure [see Clinical Pharmacology (12.3) ] , which may reduce effectiveness of HERNEXEOS. 7.2 Effects of HERNEXEOS on Other Drugs BCRP Substrates Avoid concomitant use of HERNEXEOS with certain BCRP substrates where minimal concentration changes may lead to serious adverse reactions. If coadministration cannot be avoided, monitor for increased adverse reactions and follow recommendations provided in the approved product labeling for the BCRP substrate. For other BCRP substrates, monitor for increased adverse reactions and adjust the dosages of those substrates as clinically appropriate. Zongertinib is a BCRP inhibitor. HERNEXEOS increases exposure of BCRP substrates [see Clinical Pharmacology (12.3) ] , which may increase the risk of adverse reactions related to these substrates.