Barinthus Biotherapeutics plc (BRNS)

Barinthus Biotherapeutics plc was a clinical-stage biopharmaceutical company developing T cell immunotherapeutics aimed at chronic infectious disease, autoimmunity and cancer. The company was founded in 2016 as Vaccitech, a spin-out from the University of Oxford, and was based in Harwell, near Oxford, in the United Kingdom, with a presence in the United States.

Its technology platforms included viral vector approaches used to generate T cell responses and the SNAP-TI and SNAP-CI platforms for tolerance-inducing and cancer immunotherapy applications. Pipeline candidates included VTP-300 for chronic hepatitis B, VTP-200 for persistent high-risk HPV, VTP-1000 for celiac disease, VTP-850 for recurrent prostate cancer and VTP-1100 for HPV-related cancer.

The company is also known for the adenoviral vector technology it licensed to AstraZeneca, which was used in the Oxford-AstraZeneca COVID-19 vaccine. Vaccitech listed American depositary shares on Nasdaq under the symbol VACC in 2021. In November 2023 it changed its name to Barinthus Biotherapeutics and its symbol to BRNS.

Like many clinical-stage companies, Barinthus had no commercial product revenue and relied on collaboration and royalty income and its cash reserves. In 2025 it carried out a strategic review of its programs and capital allocation, which led to the merger discussions that followed.

On September 29, 2025, Barinthus signed a merger agreement with Clywedog Therapeutics, Inc., a privately held Delaware company, with the agreement amended in February 2026. The structure used a new Delaware holding company, Beacon Topco, Inc., a court-sanctioned scheme of arrangement under English law, and a merger, after which Topco would be renamed Clywedog Therapeutics Holdings, Inc. The scheme exchange ratio was set at 0.111 shares of Topco common stock per Barinthus ordinary share.

A hearing before the High Court in London was held on September 1, 2026, and the scheme became effective in early September. Nasdaq trading in the Barinthus ADSs was suspended on completion, the company asked Nasdaq to file a Form 25, and it planned to file a Form 15 to suspend its SEC reporting. Topco's common stock was expected to list on Nasdaq under the symbol CLYD.