Prothena Corporation Announces Significant Workforce Reduction and Substantial Operating Cost Reduction

Strategic Insights -

Prothena Corporation Public Limited Company, a multinational biotechnology company, has announced an approximate 63% reduction in its workforce in order to substantially reduce its operating costs to those necessary to support its remaining wholly-owned programs, its obligations to partnered programs, and its anticipated business development activities. This decision follows the company's May 23, 2025 announcement of its decision to discontinue further development of birtamimab. The workforce reduction is expected to be substantially complete by the end of the fourth quarter of 2025.

Key Takeaways:

  • Prothena Corporation Public Limited Company has announced a significant workforce reduction of approximately 63% to reduce its operating costs.
  • The workforce reduction affects over 60% of the company's employees and is expected to be substantially complete by the end of the fourth quarter of 2025.
  • Affected U.S. employees are eligible to receive severance payments and benefits under the Prothena Biosciences Inc Amended and Restated Severance Plan, while non-U.S. employees are eligible to receive statutory and/or contractual payments.
  • Certain senior executives, including Chief Regulatory Officer Carol D. Karp and Chief People Officer David A. Ford, will have their employment terminated effective August 1, 2025, triggering certain payments and benefits under the Prothena Biosciences Inc Amended and Restated Severance Plan.
  • Prothena Corporation expects to recognize approximately $16 to $20 million in total for severance and related benefits for employees laid off under the reduction in workforce and non-cash share-based compensation expense related to the acceleration of stock options.
  • The company may also incur other charges or cash expenditures not currently contemplated due to events that may occur as a result of, or associated with, the reduction in workforce.

Statistics:

  • 63% workforce reduction
  • Approximately $16 to $20 million total for severance and related benefits
  • 4th quarter of 2025: expected completion of workforce reduction
  • June 18, 2025: date of announcement
  • May 23, 2025: date of announcement to discontinue further development of birtamimab
  • May 8, 2025: date of quarterly report on Form 10-Q filed with the SEC
  • March 28, 2025: date of definitive proxy statement on Schedule 14A filed with the SEC

Sources:

  • UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT
  • FORM 8-K: Current Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934
  • Prothena Biosciences Inc Amended and Restated Severance Plan
  • Schedule 14A: Definitive Proxy Statement
  • Securities Exchange Act of 1934
  • Quarterly Report on Form 10-Q filed with the SEC on May 8, 2025
  • Definitive Proxy Statement on Schedule 14A filed with the SEC on March 28, 2025