Prothena Announces Addition of Industry Veterans to Board of Directors

Prothena Announces Addition of Industry Veterans to Board of Directors

Richard T. Collier and Shane Cooke Join Board of Directors

DUBLIN, Ireland, Jan. 7, 2013 (GLOBE NEWSWIRE) -- Prothena Corporation plc
(Nasdaq:PRTA), a biotechnology company focused on the discovery and
development of novel antibodies for the potential treatment of a broad range
of diseases, today announced the appointment of Richard T. Collier and Shane
Cooke to its board of directors. Mr. Collier and Mr. Cooke join existing
directors Lars Ekman, Chairman of the Board of Directors, and Dale Schenk, CEO
of Prothena.

"We are pleased and proud that Rick and Shane will be joining our Board. Each
has significant industry experience and their insight will be invaluable to us
as we seek to develop novel antibodies for the potential treatment of a broad
range of diseases, and advance these potential therapies through clinical
development," commented Lars Ekman, Prothena's Chairman. "On behalf of
Prothena and the Board of Directors, I welcome them and look forward to
drawing on their experience and judgment."

Richard T. Collier

Richard T. Collier is currently an Adjunct Professor of Law at The Temple
University Beasley School of Law in Philadelphia, where he has taught Drug and
Medical Device Law since 2004. He has nearly twenty-five years experience in
executive positions in the global pharmaceutical and biotechnology industries.
Among other positions, Mr. Collier served as Senior Vice President and General
Counsel in three publicly-traded global pharmaceutical companies -
Rhone-Poulenc Rorer Inc.; Pharmacia & Upjohn Company; and Pharmacia
Corporation. Most recently, Mr. Collier served as Executive Vice President and
General Counsel of Elan Corporation, plc. Prior to his corporate career, Mr.
Collier was in the private practice of law at two leading Philadelphia-based
law firms and served with the U.S. Federal Trade Commission in Washington,
D.C. and the U.S. Department of Justice in Philadelphia. Mr. Collier earned
both his undergraduate (B.A.) and law degrees (J.D.) at Temple University in
Philadelphia.

Shane Cooke

Shane Cooke is President of Alkermes plc and previously, was Head of Elan Drug
Technologies (EDT) and Executive Vice President of Elan Corporation, plc from
2007 until the merger between EDT and Alkermes, Inc. in September 2011. Mr.
Cooke concurrently served as Chief Financial Officer of Elan Corporation, plc
from 2001 to May 2011 and as a Director of Elan from May 2005 to September
2011. Prior to joining Elan, Mr. Cooke was Chief Executive of Pembroke Capital
Limited, an aviation leasing company of which he was a founder. Mr. Cooke also
previously held a number of senior positions in finance in the banking and
aviation industries. Mr. Cooke is a chartered accountant and a graduate of
University College Dublin, Ireland.

About Prothena Corporation

Prothena Corporation plc (Nasdaq:PRTA) is a biotechnology company focused on
the discovery and development of novel antibodies for the potential treatment
of a broad range of diseases that involve protein misfolding or cell adhesion,
particularly on the discovery and development of potential therapeutic
monoclonal antibodies directed specifically to disease-causing proteins. These
potential therapies have a broad range of indications, including AL and AA
forms of amyloidosis, Parkinson's disease and related synucleinopathies, and
novel cell adhesion targets involved in autoimmune disease and metastatic
cancers. For more information, please visit www.prothena.com.

Forward-Looking Statements

This press release contains forward-looking statements within the meaning of
the Section 27A of the Securities Act of 1933 and Section 21E of the
Securities Exchange Act of 1934. These statements relate to, among other
things, our financial condition, results of operations and business prospects
and the status and timing of our products in research.These forward-looking
statements are identified by their use of terms and phrases such as
"anticipate," "believe," "could," "estimate," "expect," "intend," "may,"
"plan," "predict," "project," "potential,""target," "will" and similar terms
and phrases, including references to assumptions.These statements are based
on assumptions that may not prove accurate. Actual results could differ
materially from those anticipated due to known and unknown risks,
uncertainties and other factors including, but not limited to the risks and
uncertainties described in the "Risk Factors" section of the information
statement included as an exhibit to our registration statement on Form 10,
which has been declared effective by the Securities and Exchange
Commission.Prothena undertakes no obligation to update publicly any
forward-looking statements contained in this press release as a result of new
information, future events or changes in Prothena's expectations.

CONTACT: Paul Cox, Stern Investor Relations, Inc.
         212.362.1200, paul@sternir.com