If You Invested in Verona Pharma (VRNA)

Verona Pharma plc (historically traded on Nasdaq under the ticker VRNA) is a biopharmaceutical company focused on developing and commercializing therapies for chronic respiratory diseases with significant unmet medical needs. According to company disclosures, Verona Pharma concentrates on chronic obstructive pulmonary disease (COPD) and other chronic respiratory conditions, and its work centers on therapies designed to address persistent symptoms in these patient populations.

Verona Pharma’s first commercial product is Ohtuvayre (ensifentrine), which the company describes as the first inhaled therapy for the maintenance treatment of adults with COPD that combines bronchodilator and non-steroidal anti-inflammatory activities in a single molecule. Ohtuvayre is a first-in-class selective dual inhibitor of phosphodiesterase 3 and 4 (PDE3 and PDE4) and represents a novel inhaled mechanism for COPD maintenance treatment. Verona has evaluated nebulized Ohtuvayre in its Phase 3 ENHANCE clinical program ("Ensifentrine as a Novel inHAled Nebulized COPD thErapy"), where Ohtuvayre met the primary endpoint in both ENHANCE-1 and ENHANCE-2, demonstrating statistically significant and clinically meaningful improvements in lung function in COPD patients.

Beyond COPD, Verona Pharma states that ensifentrine has potential applications in other respiratory diseases, including non-cystic fibrosis bronchiectasis, cystic fibrosis, asthma and other respiratory conditions. The company is conducting and supporting clinical studies to assess ensifentrine in non-cystic fibrosis bronchiectasis and is progressing a fixed-dose combination of ensifentrine with glycopyrrolate, a long-acting muscarinic antagonist (LAMA), as a nebulized maintenance treatment for COPD. These programs reflect Verona’s focus on chronic respiratory diseases and on mechanisms that may improve lung function, reduce exacerbations and address symptoms such as dyspnea and quality of life measures in defined COPD subgroups.

Verona Pharma has reported that Ohtuvayre is indicated in the United States for the maintenance treatment of COPD in adult patients and that it is not intended for relief of acute bronchospasm. Company communications highlight that Ohtuvayre is being evaluated and discussed in major respiratory medicine forums, including presentations at the European Respiratory Society (ERS) International Congress and the American Thoracic Society (ATS) Conference, where additional analyses from the ENHANCE Phase 3 program, nonclinical studies and real-world data have been presented. These analyses include subgroup data in patients with COPD and comorbid cardiac disorders, type 2 diabetes, and varying baseline dyspnea levels.

According to Verona Pharma, Ohtuvayre’s safety profile includes warnings and precautions such as the risk of paradoxical bronchospasm and psychiatric events including suicidality, as well as common adverse reactions like back pain, hypertension, urinary tract infection and diarrhea. The company emphasizes that Ohtuvayre should not be used for the relief of acute symptoms and that patients should have access to a short-acting bronchodilator for rescue therapy.

Verona Pharma has also described its broader development and commercial activities around Ohtuvayre, including a U.S. launch that has generated growing prescriptions and net sales, and regulatory and development collaborations in other territories. For example, the company has reported regulatory approval of Ohtuvayre in Macau for the maintenance treatment of COPD in adult patients through a development partner in Greater China, and it has referenced ongoing regulatory activities related to potential marketing authorization applications in the European Union and the United Kingdom. Verona has also noted a pivotal Phase 3 trial of ensifentrine for COPD in China being conducted by its Greater China partner.

From a corporate standpoint, Verona Pharma historically operated as a public company with American Depositary Shares (ADSs) listed on the Nasdaq Global Market under the symbol VRNA. In July 2025, Verona Pharma announced that it had entered into a definitive transaction agreement under which Merck Sharp & Dohme LLC, through a wholly owned subsidiary, would acquire Verona Pharma by means of a court-sanctioned English law scheme of arrangement. Subsequent company and Merck announcements, as well as Verona’s filings with the U.S. Securities and Exchange Commission (SEC), describe shareholder approval of the transaction, court sanction of the scheme, and completion of the acquisition.

On October 7, 2025, Merck announced the completion of the acquisition of Verona Pharma, stating that Verona Pharma had become a wholly owned subsidiary of Merck. An accompanying Form 8-K filed by Verona Pharma on the same date reports that Merck and its acquisition vehicle consummated the transaction, that Bidco (a Merck subsidiary) acquired all issued and outstanding Verona Pharma ordinary shares, and that holders of Verona ADSs became entitled to receive cash consideration per ADS as specified in the transaction agreement. The Form 8-K further notes that, in connection with the transaction, Verona requested suspension of trading of its ADSs on Nasdaq and that Nasdaq would file a Form 25 to delist and deregister the ADSs under Section 12(b) of the Exchange Act.

A Form 25 (Form 25-NSE) filed with the SEC on October 7, 2025, identifies Verona Pharma plc as the issuer and the Nasdaq Stock Market LLC as the exchange, and serves as notification of removal from listing and/or registration of Verona’s American Depositary Shares. Verona’s Form 8-K dated October 7, 2025 also states that the company intends to file a Form 15 to terminate registration of its shares and ADSs and to suspend its reporting obligations under Sections 13(a) and 15(d) of the Exchange Act. As a result of these steps, Verona Pharma’s ADSs are no longer listed or traded on the Nasdaq Global Market, and the company has become an indirect wholly owned subsidiary of Merck.

For investors researching the historical VRNA stock, Verona Pharma represents a case of a respiratory-focused biopharmaceutical company whose value proposition was closely tied to a first-in-class COPD maintenance therapy and a pipeline centered on ensifentrine. Its subsequent acquisition by Merck, the delisting of its ADSs from Nasdaq, and the planned deregistration of its securities mean that Verona Pharma’s equity is no longer available as a standalone publicly traded investment, and information about the company’s ongoing operations is now part of Merck’s broader corporate structure and disclosures.