Prothena SEC Filings

PROTHENA CORP PUBLIC LTD CO director William H. Dunn Jr. received a grant of stock options covering 27,000 ordinary shares. The options have an exercise price of $9.76 per share, expire on May 15, 2036, and will vest 100% on the earlier of the first anniversary of the grant date or the company’s 2027 annual general meeting, assuming continuous board service.

PROTHENA CORP PUBLIC LTD CO director Shane Cooke received a grant of stock options covering 27,000 Ordinary Shares. The options carry an exercise price of $9.76 per share and expire on May 15, 2036. This is a compensation-related award, not an open-market purchase.

According to the terms, all 27,000 options will vest and become exercisable on the earlier of the first anniversary of the grant date or the day of the company’s 2027 annual general meeting, assuming he continues serving as a director until that vesting date.

PROTHENA CORP PUBLIC LTD CO director Richard T. Collier received a grant of stock options covering 27,000 ordinary shares. The options have an exercise price of $9.76 per share and expire on May 15, 2036. According to the award terms, all 27,000 options will vest and become exercisable on the earlier of the first anniversary of the May 15, 2026 grant date or the day of Prothena’s 2027 annual general meeting, provided he continues to serve as a director through that vesting date.

Prothena Corporation plc reported the results of its annual general meeting of shareholders. Shareholders re-elected Shane M. Cooke and Dennis J. Selkoe to the Board of Directors to serve until no later than the annual general meeting in 2029.

Shareholders also ratified, in a non-binding vote, the appointment of KPMG LLP as independent registered public accounting firm for the fiscal year ending December 31, 2026, and gave the Board, through its Audit Committee, binding authority to approve the auditor’s remuneration. In a separate non-binding advisory vote, shareholders approved the compensation of the Company’s named executive officers.

Prothena Corporation plc Schedule 13G/A shows Rubric Capital Management and related reporting person David Rosen hold 5,000,000 Ordinary Shares, representing 9.29% of the class. The filing states the share count basis is 53,832,982 Ordinary Shares outstanding as of March 2, 2026. The cover page reports the position is held with shared voting and shared dispositive power by the reporting persons. The statement identifies Rubric Capital Master Fund LP as a Rubric Fund with rights to dividends or sale proceeds on more than 5% of the class.

PROTHENA CORP PUBLIC LTD CO insider William P. Scully filed an initial ownership report as a ten percent owner of PRTA. He reports 736,000 ordinary shares held directly, plus 80,000 shares held indirectly through Manatee Equity Fund LLC and 52,000 shares held indirectly by his spouse. A footnote states he disclaims beneficial ownership of these securities except to the extent of his pecuniary interest.

Prothena Corp Public Ltd: William P. Scully filed an amended Schedule 13G/A reporting beneficial ownership of 5,378,846 Ordinary Shares, representing approximately 10.27% of the company's 52,353,237 shares outstanding as of April 30, 2026. The filing breaks ownership into positions with 793,000 shares of sole voting/dispositive power and 4,585,846 shares of shared voting/dispositive power.

Prothena Corporation plc reported a profitable quarter for the period ended March 31, 2026. Total revenue rose to $51.1 million, driven mainly by a $50.0 million development milestone payment from Novo Nordisk related to coramitug, alongside $1.0 million of collaboration revenue from Bristol Myers Squibb.

The company generated net income of $32.7 million, or $0.60 per diluted share, compared with a net loss of $60.2 million a year earlier. Research and development expense fell to $12.6 million from $50.8 million, reflecting lower spend after discontinuing birtamimab and the impact of a $4.2 million net reduction in restructuring costs.

Cash and cash equivalents were $329.5 million, and management believes this balance will fund operations for at least 12 months. Prothena repurchased 788,990 ordinary shares for about $7.3 million and ended the quarter with 53.1 million shares outstanding and shareholders’ equity of $312.6 million, while continuing to advance late-stage programs with Roche, Novo Nordisk and Bristol Myers Squibb.

Prothena Corporation plc reported strong first quarter 2026 results, with total revenue of $51.1 million and net income of $32.7 million, compared with a net loss of $60.2 million a year earlier. Results were driven mainly by a $50 million milestone payment from Novo Nordisk and lower research and development and general and administrative expenses, plus a $4.2 million restructuring credit.

Quarter-end cash, cash equivalents and restricted cash were $330.3 million and the company had no debt. Prothena cut its projected 2026 net cash used in operating and investing activities to $18–$23 million and now expects to end 2026 with about $273 million in cash (midpoint). It also authorized a 2026 share repurchase program for up to $100 million, repurchasing 788,990 shares for $7.3 million through March 31, 2026.

Operationally, Novo Nordisk obtained U.S. FDA Fast Track designation for coramitug and paid the $50 million milestone, Roche presented multiple positive prasinezumab data updates, Prothena completed a Phase 1 study for PRX019 with potential for a $55 million milestone from Bristol Myers Squibb, and preclinical CYTOPE and PRX012-TfR programs continued to advance.