Prothena Corporation plc (NASDAQ: PRTA) Investor Securities Class Action Lawsuit 05/15/2018

You must submit the settlement "Proof" form attached below, in order to participate in this settlement. There is a strict deadline of November 25, 2019 by which all claims must be submitted. The instructions for submitting are included in the "Proof" and the "Notice" files attached below for your download. DO NOT SEND THE FORMS TO THE SHAREHOLDERS FOUNDATION, FOLLOW THE DIRECTIONS IN THE "PROOF".

To have your information reviewed for options and to recieve notifications about this case, please use this form. You may also send an email to, or call us at (858) 779-1554.
Company Name(s): 
Case Name: 
Prothena Shareholder Class Action Lawsuit 05/15/2018
Case Status: 
Settlement Proposed
Affected Securities
Lawsuit Overview
Type of Lawsuit: 
Shareholder Class Action
Date Filed: 
Class Period Begin: 
Class Period End: 
Court of Filing: 
U.S. District Court for the Northern District of California
Deadline To File for Lead: 
Date Settled: 
Settlement Amount: 
Deadline to Participate in Settlement: 
Settlement Notice: 
Settlement Proof: 

September 12, 2019 - The court preliminarily approved the settlement.

August 26, 2019 - Parties filed a stipulation of settlement.

July 25, 2018 - The court denied the lead plaintiff motions and ordered the case closed.

July 16, 2018 - Lead plaintiff motions were filed.

July 5, 2018 - The plaintiff filed a notice of voluntary dismissal without prejudice.

May 15, 2018 - An investor in shares of Prothena Corporation plc (NASDAQ: PRTA) filed a lawsuit in the U.S. District Court for the Northern District of California over alleged violations of Federal Securities Laws by Prothena Corporation plc in connection with certain allegedly false and misleading statements made between October 15, 2015 and April 20, 2018.

Ireland based Prothena Corporation plc, a late-stage clinical biotechnology company, focuses on the discovery, development, and commercialization of novel immunotherapies for the treatment of diseases in the neuroscience and orphan categories.

On October 15, 2015, Prothena Corporation plc announced its late-stage Phase 2b “PRONTO” study and expansion of its Phase 1/2 clinical trial for the antibody NEOD001.

On April 23, 2018, Prothena Corporation plc announced that it "is discontinuing development of NEOD001, an investigational antibody that was being evaluated for the treatment of AL amyloidosis."Prothena Corporation plc advised investors that "[b]ased on the results from the Phase 2b PRONTO study, which did not meet its primary or secondary endpoints, the Company asked the independent data monitoring committee (DMC) of the Phase 3 VITAL study to review a futility analysis of the ongoing VITAL study. The DMC recommended discontinuation of the VITAL study for futility." Shares of Prothena Corporation plc (NASDAQ: PRTA) declined to as low as $10.43 per share on April 25, 2018.

According to the complaint the plaintiff alleges on behalf of purchasers of Prothena Corporation plc (NASDAQ: PRTA) common shares between October 15, 2015 and April 20, 2018, that the defendants violated Federal Securities Laws. More specifically, the plaintiff claims that between October 15, 2015 and April 20, 2018, Prothena Corporation plc violated the Exchange Act by misleading investors regarding its development of NEOD001, an antibody designed to treat AL amyloidosis, a debilitating disease that can lead to organ failure and death. The plaintiff alleges that between October 15, 2015 and April 20, 2018, defendants misleadingly cited the results of Prothena Corporation plc’s ongoing Phase 1/2 clinical study of NEOD001 as evidence that the drug was effective and provided a strong basis for late-stage Phase 2b and Phase 3 studies of NEOD001, while in truth, NEOD001 was not an effective treatment for AL amyloidosis and did not provide an adequate basis for the late-stage Phase 2b and Phase 3 studies.