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Prothena Corporation PLC (PRTA)



Faruqi & Faruqi, LLP Encourages Investors Who Suffered Losses Exceeding $50,000 In Prothena Corporation plc To Contact The Firm

Faruqi & Faruqi, LLP, a leading national securities law firm, reminds investors in Prothena Corporation plc (“Prothena” or the “Company”) (NASDAQ:PRTA) of the July 16, 2018 deadline to seek the role of lead plaintiff in a federal securities class action that has been filed against the Company.

If you invested in Prothena stock or options between October 15, 2015 to April 20, 2018 and would like to discuss your legal rights, please fill out the form below.  There is no cost or obligation to you.  You can also contact us by calling Richard Gonnello toll free at 877-247-4292 or at 212-983-9330 or by sending an e-mail to rgonnello@faruqilaw.com. 

The lawsuit has been filed in the U.S. District Court for the Northern District of California on behalf of all those who purchased Prothena’s publicly traded common stock between October 15, 2015 and April 20, 2018 (the “Class Period”).  The case, Arkansas Teacher Retirement System v. Prothena Corporation plc et al, No. 3:18-cv-02865 was filed on May 15, 2018.

The lawsuit focuses on whether the Company and its executives violated federal securities laws by: 1) Deliberately withholding relevant trial data that cut against the Company’s consistently positive statements; 2) Making misleading comparisons between the response rates of NEOD001, the Company’s principle drug for the treatment of amyloid light chain amyloidosis, and prior studies that evaluated patient response; and 3) Touting the results of its ongoing Phase 1/2 trial as a strong predicate for the likely success of the Phase 2b PRONTO study and Phase 3 VITAL study, despite knowing from the full results of the Phase 1/2 study that NEOD001 was not effective.

Specifically, on June 29, 2017, the investment research firm Muddy Waters published a report questioning whether NEOD001 was effective and openly accused Prothena of presenting the early trial data in a misleading manner and having “selectively designed their trials to skew results.”

Following the release of the report, Prothena’s share price fell from a high of $54.66 per share on June 29, 2017 to an intraday low of $49.71 - a $4.95 or a 9.06% drop.

On November 8, 2017, Kerrisdale, another investment research firm, published a 27-page report alleging that Prothena’s best response measure “is a poor indicator of efficacy” and presents a “blatant apples-to-oranges” comparison with prior studies.

On this report, Prothena’s share price fell from $60.96 per share on November 7, 2017 to a closing price of $56.24 on November 8, 2017 - a $4.73 or a 7.75% drop.

On February 2, 2018, Prothena abruptly announced that its Chief Medical Officer, Sarah Noonberg, had resigned.

On this news, Prothena’s share price fell from $39.60 per share on February 2, 2018 to a closing price of $32.14 on February 5, 2018 - a $7.46 or a 18.84% drop.

On April 23, 2018, premarket, Prothena announced that it was ending all development of NEOD001 after data from its Phase 2b PRONTO trial showed that NEOD001 failed to reach either its primary or secondary endpoints.

Following this announcement, Prothena’s share price fell from $36.84 per share on April 20, 2018 to a closing price of $11.50 on April 23, 2018 - a $25.34 or a 68.78% drop.

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  • Case:
    Prothena Corporation PLC (PRTA)

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Contact Counsel

Richard W. Gonnello
Faruqi & Faruqi, LLP
685 Third Avenue 26th Floor
New York, NY 10017
Tel: (212) 983-9330


Case Details


  • 05/22/2018

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