U.S. FDA Grants Priority Review to Supplemental New Drug Application for HYRNUO® (sevabertinib) Under Investigation as a First-Line Treatment of HER2-Mutated Non-Small Cell Lung Cancer

• Regulatory submission for first-line use of HYRNUO is based on results from the ongoing Phase I/II SOHO-01 trial evaluating the efficacy and safety in patients with advanced HER2-mutated non-small cell lung cancer (NSCLC) who have not received prior therapy

• The U.S. Food and Drug Administration (FDA) grants Priority Review designation for the evaluation of medicines that, if approved, would provide significant improvement in the safety or effectiveness of the treatment, prevention, or diagnosis of a serious condition¹
   

WHIPPANY, N.J., May 18, 2026 – Bayer announced today that the U.S. Food and Drug Administration (FDA) has granted HYRNUO® (sevabertinib) Priority Review status for the first-line treatment of adult patients with locally advanced or metastatic non-small cell lung cancer (NSCLC) whose tumors have HER2 (ERBB2) tyrosine kinase domain (TKD) activating mutations in patients with no prior therapy. HYRNUO is not currently approved in this first-line setting.

In November 2025, HYRNUO received U.S. FDA accelerated approval for patients with locally advanced or metastatic NSCLC whose tumors have HER2 TKD activating mutations, as detected by an FDA-approved test, and who have received a prior systemic therapy.² This indication is approved under accelerated approval based on objective response rate (ORR) and duration of response (DOR). Continued approval for this indication may be contingent upon verification and description of clinical benefit in a confirmatory trial.²

“There continues to be progress in understanding and treating HER2-mutated NSCLC, and Bayer is committed to further investigating the full potential of HYRNUO as a treatment option,” said Nelson Ambrogio, President, Bayer U.S. Pharmaceuticals. “We appreciate the FDA’s Priority Review designation and remain focused on working through the regulatory process to help address the needs of this patient population.”

The regulatory application for first-line use of HYRNUO is based on preliminary clinical evidence from Cohort F (patients who had not previously received treatment) of the ongoing Phase I/II SOHO-01 Study (NCT05099172) evaluating the efficacy and safety of HYRNUO in patients with locally advanced or metastatic HER2-mutated NSCLC.²

About HYRNUO 
HYRNUO is an oral, reversible, small molecule, tyrosine kinase inhibitor (TKI) that inhibits mutated human HER2, including HER2 exon 20 insertions and HER2 point mutations, as well as epidermal growth factor receptors (EGFR), with selectivity for mutated vs wild-type EGFR. HYRNUO works by blocking certain enzymes called tyrosine kinases, which are involved in the growth of cancer cells. HYRNUO is derived from Bayer’s strategic research alliance with the Broad Institute of MIT and Harvard in Cambridge, MA, USA.

About Non-Small Cell Lung Cancer (NSCLC)
Lung cancer is the leading cause of cancer-related deaths worldwide.3 NSCLC is the most common type of lung cancer, accounting for more than 85% of cases.⁴ Activating HER2 mutations are found in 2% to 4% of patients with advanced NSCLC.5 80% of people diagnosed with NSCLC have already progressed to advanced stages, which makes it difficult to treat.⁶

INDICATION
HYRNUO is indicated for the treatment of patients with locally advanced or metastatic non-squamous NSCLC whose tumors have HER2 TKD activating mutations, as detected by an FDA-approved test, and who have received a prior systemic therapy. HYRNUO is not currently approved in this first-line setting.²

This indication is approved under accelerated approval based on objective response rate (ORR) and duration of response (DOR). Continued approval for this indication may be contingent upon verification and description of clinical benefit in a confirmatory trial.

IMPORTANT SAFETY INFORMATION
Warnings & Precautions
Diarrhea
HYRNUO can cause severe diarrhea that can lead to dehydration and electrolyte imbalances. 
In the pooled safety population, diarrhea was reported in 86% of patients who received HYRNUO including Grade 3 in 15%. The median time to first onset of any grade diarrhea was four days. Dosage interruptions occurred in 15% of patients, and dose reductions occurred in 12% of patients.

At the first sign of diarrhea or increased bowel movement frequency, instruct patients to start an antidiarrheal treatment (e.g., loperamide), and to increase their fluid and electrolyte intake. Interrupt, reduce the dose or permanently discontinue HYRNUO based on severity.

Hepatotoxicity 
HYRNUO can cause severe hepatotoxicity characterized by elevations of liver function tests. 
In the pooled safety population, based on adverse reaction data, hepatotoxicity occurred in 24% of patients treated with HYRNUO including 3% Grade 3. Based on laboratory data, 35% of patients treated with HYRNUO experienced increased alanine aminotransferase (ALT), including 2.3% Grade 3. Increased aspartate aminotransferase (AST) occurred in 35% of patients treated with HYRNUO, including 2.3% Grade 3. Increased bilirubin occurred in 12% of patients treated with HYRNUO. The median time to first onset of AST or ALT elevation was 1.4 (range 0.2 to 14.5) months. HYRNUO was interrupted for an adverse reaction of hepatotoxicity in 4.1% of patients, the dose was reduced in 4.1% and permanently discontinued in 0.4%.

Monitor liver function tests including ALT, AST, and total bilirubin at baseline prior to the first administration of HYRNUO, every 2 weeks for the first month and then monthly thereafter as clinically indicated, with more frequent testing in patients who develop transaminase elevations. Interrupt, reduce the dose or permanently discontinue HYRNUO based on the severity of the adverse reaction.

Interstitial Lung Disease/Pneumonitis 
HYRNUO can cause severe interstitial lung disease (ILD)/pneumonitis. In the pooled safety population, ILD/pneumonitis occurred in two patients (0.7%) treated with HYRNUO, including 0.4% Grade 3. One patient required interruption of HYRNUO.

Monitor patients for new or worsening symptoms indicative of ILD/pneumonitis (e.g., dyspnea, cough, fever). Discontinue HYRNUO upon confirmation of ILD/pneumonitis. 

Ocular Toxicity
HYRNUO can cause ocular toxicity.
In the pooled safety population, ocular toxicity occurred in 14% of patients treated with HYRNUO, including 11% Grade 1, 2.6% Grade 2 and 0.4% Grade 3 (one case of corneal epithelial microcysts with temporary unilateral blindness).

Promptly refer patients presenting with new or worsening eye symptoms to an ophthalmologist. Interrupt, reduce the dose or permanently discontinue HYRNUO based on severity.

Pancreatic Enzyme Elevation 
HYRNUO can cause elevations of amylase and lipase levels. In the pooled safety population, based on laboratory data, increased amylase occurred in 32% of patients treated with HYRNUO, including 3.2% Grade 3 or 4. Increased lipase elevation occurred in 40% of patients treated with HYRNUO, including 10% Grade 3 or 4. Two patients (0.7%) required interruption of HYRNUO due to increased lipase and three (1.1%) required interruption of HYRNUO due to increased amylase. The median time to onset of increased amylase/lipase was 1.4 months (range: 0.2 to 17 months).

Monitor amylase and lipase regularly during treatment with HYRNUO. Interrupt, reduce the dose or permanently discontinue HYRNUO based on severity.

Embryo-fetal toxicity
Based on findings from animal studies and its mechanism of action, HYRNUO can cause fetal harm when administered to a pregnant woman. In embryo-fetal development studies, oral administration of sevabertinib to pregnant rats during the period of organogenesis resulted in alterations to growth at maternal exposures ≥0.18 times the human exposure based on area under the curve (AUC) at the clinical dose of 20 mg twice daily. Animal studies with disrupted or depleted HER2/EGFR and in vitro assays have demonstrated that inhibition of HER2 and/or EGFR results in structural abnormalities, alteration to growth, and embryo-fetal and infant mortality.

Advise pregnant women and females of reproductive potential of the potential risk to a fetus. Advise females of reproductive potential to use effective contraception during treatment with HYRNUO and for 1 week after the last dose. Advise male patients with female partners of reproductive potential to use effective contraception during treatment with HYRNUO and for 1 week after the last dose.

Adverse Reactions
In SOHO-01 (Groups D and E), serious adverse reactions occurred in 31% of patients who received HYRNUO. Serious adverse reactions in ≥2% of patients were diarrhea (6%), pneumonia (3.7%), dyspnea (2.2%), and pleural effusion (2.2%). The most common adverse reactions (>20%) in patients who received HYRNUO were diarrhea (87%), rash (66%), paronychia (33%), stomatitis (29%), and nausea (21%). The most common Grade 3 and 4 laboratory abnormalities (≥2%) were potassium decreased (13%), lipase increased (12%), lymphocyte count decreased (6%), sodium decreased (4.4%), amylase increased (3.8%), aspartate aminotransferase (AST) increased (3%), and alanine aminotransferase (ALT) increased (3%). Laboratory abnormalities in <20% of patients who received HYRNUO include blood bilirubin increased (14%; all were Grades 1 or 2). Clinically relevant adverse reactions in <10% of patients who received HYRNUO included edema (8%), cardiac arrhythmia (6%; includes arrhythmia, atrioventricular block complete, electrocardiogram QT prolonged, sinus bradycardia, sinus tachycardia, supraventricular extrasystoles, supraventricular tachycardia, tachycardia) and alopecia (3.7%).

Drug Interactions
Effects of Other Drugs on HYRNUO - Sevabertinib is a CYP3A substrate. Concomitant use with a strong or moderate CYP3A inhibitor may increase sevabertinib plasma concentrations, which may increase the risk of HYRNUO adverse reactions. Monitor patients for increased HYRNUO-associated adverse reactions with moderate CYP3A inhibitors. Avoid concomitant use of HYRNUO with strong CYP3A inhibitors. If concomitant use cannot be avoided, reduce HYRNUO dose.

Concomitant use with a strong or moderate CYP3A inducer may decrease sevabertinib plasma concentrations, which may decrease the effectiveness of HYRNUO. Avoid concomitant use of HYRNUO with strong or moderate CYP3A inducers.

Effects of HYRNUO on Other Drugs – Sevabertinib is a weak to moderate CYP3A inhibitor. Sevabertinib increases exposure of CYP3A substrates, which may increase the risk of adverse reactions related to these substrates. Avoid concomitant use of HYRNUO with CYP3A substrates where minimal increases in the concentration may lead to serious adverse reactions unless otherwise recommended in the Prescribing Information of the CYP3A substrate.

Sevabertinib is a P-gp inhibitor. Sevabertinib increases exposure of P-gp substrates, which may increase the risk of adverse reactions related to these substrates. Refer to the Prescribing Information for P-gp substrates where minimal increases in the concentration may lead to serious adverse reactions.

Sevabertinib is an inhibitor of CYP1A1 in vitro. Sevabertinib may increase exposure of CYP1A1 substrates, which may increase the risk of adverse reactions related to these substrates. Refer to the Prescribing Information of CYP1A1 substrates.

Please see full Prescribing Information.

About Oncology at Bayer
Bayer is committed to delivering science for a better life by advancing a portfolio of innovative treatments. The company has the passion and determination to develop new medicines that help improve and extend the lives of people living with cancer. The oncology franchise at Bayer includes several marketed products across diverse indications and multiple compounds in different stages of clinical development. We have a wealth of expertise in areas including: Tumor Intrinsic Pathways, Targeted Radionuclide Therapies, and Next-Generation Immuno-Oncology. We are advancing prostate cancer treatment from early to metastatic stage, with the goal of extending survival while limiting side effects. Part of Bayer’s focus on innovative precision oncology treatments, includes an approved TRK inhibitor exclusively designed to treat tumors that have an NTRK gene fusion, the oncogenic driver of tumor growth and spread.

About Bayer
Bayer is a global enterprise with core competencies in the life science fields of health care and nutrition. In line with its mission, “Health for all, Hunger for none,” the company’s products and services are designed to help people and the planet thrive by supporting efforts to master the major challenges presented by a growing and aging global population. Bayer is committed to driving sustainable development and generating a positive impact with its businesses. At the same time, the Group aims to increase its earning power and create value through innovation and growth. The Bayer brand stands for trust, reliability and quality throughout the world. In fiscal 2025, the Group employed around 88,000 people and had sales of 45.6 billion euros. R&D expenses amounted to 5.8 billion euros. 

© 2026 Bayer 
BAYER and the Bayer Cross and HYRNUO are registered trademarks of Bayer.
 

Media Contact:
Polina Miklush, Tel +1 862.431.8817 
Email: polina.miklush@bayer.com

^{Forward-Looking Statements 
This release may contain forward-looking statements based on current assumptions and forecasts made by Bayer management. Various known and unknown risks, uncertainties and other factors could lead to material differences between the actual future results, financial situation, development or performance of the company and the estimates given here. These factors include those discussed in Bayer’s public reports which are available on the Bayer website at www.bayer.com. The company assumes no liability whatsoever to update these forward-looking statements or to conform them to future events or developments.} 
 

^References

<sup>1. U.S. Food and Drug Administration. “Priority Review.” https://www.fda.gov/patients/fast-track-breakthrough-therapy-accelerated-approval-priority-review/priority-review. Accessed April 2026. 
2. HYRNUO® (sevabertinib) [Prescribing Information]. Whippany, NJ: Bayer HealthCare Pharmaceuticals, Inc.; November 2025.
3. World Health Organisation, Lung Cancer: available from: https://www.who.int/news-room/fact-sheets/detail/lung-cancer 
4. Emily Geraci, Lipika Chablani, Immunotherapy as a second-line or later treatment modality for advanced non-small cell lung cancer: A review of safety and efficacy, Critical Reviews in Oncology/Hematology, available from: https://www.sciencedirect.com/science/article/abs/pii/S1040842820301475 
5. Stephens P, Hunter C, Bignell G, et al. Lung cancer: intragenic ERBB2 kinase mutations in tumours. Nature 2004;431:525-526 
6. Yale Medicine Factsheet – Non-Small Cell Lung Cancer. Available at: https://www.yalemedicine.org/conditions/non-small-cell-lung-cancer</sup>