Shares in Dublin-based Prothena surge as it seeks to raise $67.8m

Nasdaq-listed company was spun out of Irish drugmaker Elan back in 2012

Shares in Dublin-based, Nasdaq-listed biotech company Prothena jumped by almost 17 per cent on Wednesday after it said it intends to raise $67.8 million (€57.3 million) through a public offering.

The company, which was spun out of Irish drugmaker Elan in 2012, specialises in developing immune system-based drugs to fight progressive diseases. The company has expertise in protein dysregulation and a pipeline of novel investigational therapeutics for rare peripheral amyloid and neurodegenerative diseases.

Prothena has priced an underwritten public offering of 3,500,000 of its ordinary shares at a price to the public of $20.75 per ordinary share. In addition, the company has granted underwriters a 30-day option to purchase up to an additional 525,000 of shares.

The offering is expected to close on Friday.



Citigroup, Jefferies and Cantor are acting as lead book-running managers, Oppenheimer is acting as book-running manager, and BTIG and HC Wainwright are acting as co-lead managers for the offering.

Prothena, which was previously backed by disgraced British investor Neil Woodford, found itself in difficulties three years ago when a drug it was developing for treating a rare disease called AL amyloidosis failed in a crucial clinical trial.

News of the failure led to the company’s shares plunging 70 per cent in one day. The drug was subsequently discontinued.

Charlie Taylor

Charlie Taylor

Charlie Taylor is a former Irish Times business journalist