Prothena Corporation plc
May 21, 2015

Prothena Announces Presentation of Clinical Data From the Ongoing Phase 1/2 NEOD001 Study and Systemic Amyloidosis Patient Survey Results at 20th Congress of the European Hematology Association

DUBLIN, Ireland, May 21, 2015 (GLOBE NEWSWIRE) -- Prothena Corporation plc (Nasdaq:PRTA), a late-stage clinical biotechnology company focused on the discovery, development and commercialization of novel protein immunotherapy programs, today announced that Dr. Michaela Liedtke will give an oral presentation of clinical data from its ongoing Phase 1/2 trial of NEOD001 in patients with AL amyloidosis and persistent organ dysfunction at the 20th Congress of the European Hematology Association (EHA) to be held June 11 - 14, 2015 in Vienna, Austria. In addition, the Amyloidosis Research Consortium will present results from a survey of patients with systemic amyloidosis conducted in collaboration with Prothena.

The presentation sessions can be accessed as follows:

(Abstract #S104) Phase 1/2 study of NEOD001 in patients with AL amyloidosis and persistent organ dysfunction

Data contained in the published abstract was current as of September 30, 2014. Updated clinical data from the ongoing Phase 1/2 trial of NEOD001 will be presented at EHA.

(Abstract # E1262) Patient Experience with Light Chain Amyloidosis: A Survey from the Amyloidosis Research Consortium

About NEOD001

NEOD001 is a humanized monoclonal antibody that specifically targets the circulating soluble amyloid and deposited insoluble amyloid that accumulates in both the AL and AA forms of amyloidosis. The ongoing multi-center Phase 1/2 clinical trial is evaluating the safety, tolerability, pharmacokinetics and immunogenicity of NEOD001 in patients with AL amyloidosis and persistent organ dysfunction. The study is also evaluating exploratory biomarkers for cardiac and renal function. Separately, The VITAL Amyloidosis Study, a double-blind, placebo-controlled, global Phase 3 registrational trial will evaluate NEOD001 in newly-diagnosed, treatment-naïve patients with AL amyloidosis, and will assess all-cause mortality and cardiac hospitalizations in addition to biomarker, functional and quality of life endpoints. For more information on both the Phase 1/2 and VITAL Phase 3 trials, please visit www.clinicaltrials.gov, and search identifiers NCT01707264 (Phase 1/2) and NCT02312206 (VITAL Phase 3).

About AL Amyloidosis

Systemic amyloidoses are a complex group of progressive diseases caused by tissue deposition of misfolded proteins that result in progressive organ damage. The most common type, AL amyloidosis or primary amyloidosis, involves a hematological disorder caused by plasma cells that produce misfolded AL protein resulting in deposits of abnormal AL protein (amyloid) in the tissues and organs of individuals with this disease. There are no approved treatments for AL amyloidosis that directly target potentially toxic forms of the AL protein. AL amyloidosis is a rare disorder and it is estimated that about 30,000 to 45,000 patients in the U.S. and Europe suffer from this disease. Both the causes and origins of AL amyloidosis remain poorly understood. For more information on AL amyloidosis, please visit the websites of the Amyloidosis Support Group and the Amyloidosis Foundation.

About Prothena

Prothena Corporation plc is a late-stage clinical biotechnology company focused on the discovery, development and commercialization of novel protein immunotherapy programs for the potential treatment of diseases that involve amyloid or cell adhesion. The Company is developing antibody-based product candidates that target a number of potential indications including AL amyloidosis (NEOD001), Parkinson's disease and other related synucleinopathies (PRX002), and psoriasis and other inflammatory diseases (PRX003).

For more information, please visit the Company's website at www.prothena.com.

CONTACT: Investors: Tran Nguyen, CFO

         650-837-8535, IR@prothena.com

         

         Media: Angela Bitting

         925-202-6211, angela.bitting@prothena.com