Prothena Reports Third Quarter 2025 Financial Results and Business Highlights
-
Net cash used in operating and investing activities was
$40.6 million $140.4 million $331.7 million - Roche to initiate the Phase 3 PARAISO clinical trial evaluating prasinezumab, a potential first-in-class anti-alpha-synuclein antibody, for early-stage Parkinson's disease by end of 2025
- Novo Nordisk initiated the Phase 3 CLEOPATTRA clinical trial evaluating coramitug, a potential first-in-class amyloid depleter, for ATTR amyloidosis with cardiomyopathy
- Novo Nordisk to present Phase 2 results for coramitug during a late-breaking session at the American Heart Association Scientific Sessions on November 10, 2025
-
Bristol Myers Squibb obtained Fast Track designation from the
U.S. FDA for BMS-986446 (PRX005), an anti-MTBR-tau-targeting antibody, for the treatment of Alzheimer’s disease - Prothena will convene an Extraordinary General Meeting on November 19, 2025 to obtain shareholder approval on a proposal reducing share capital to create distributable reserves to support a share redemption program to be conducted in 2026 if deemed appropriate
-
Potential to earn up to
$105 million
“We are pleased with the advancement of our late-stage partnered clinical programs. Novo Nordisk recently initiated the Phase 3 CLEOPATTRA clinical trial evaluating coramitug in ATTR-CM and Roche plans to initiate the Phase 3 PARAISO clinical trial evaluating prasinezumab in early-stage Parkinson’s disease by the end of 2025. Recently, Bristol Myers Squibb obtained Fast Track designation from the
Third Quarter, Recent Business Highlights and Upcoming Milestones
Updates on Active Clinical Development Portfolio
Prasinezumab, a potential first-in-class antibody for the treatment of Parkinson’s disease that is designed to target a key epitope within the C-terminus of alpha-synuclein and is the focus of a worldwide collaboration with Roche.
- Partner Roche to initiate the Phase 3 PARAISO clinical trial evaluating prasinezumab for early-stage Parkinson's disease by the end of 2025 (NCT07174310)
-
Roche has stated that prasinezumab has peak sales potential greater than
$3.5 billion
Coramitug (formerly PRX004), a potential first-in-class amyloid depleter antibody for the treatment of ATTR amyloidosis with cardiomyopathy (ATTR-CM) designed to deplete the pathogenic, non-native forms of the transthyretin (TTR) protein, is being developed by Novo Nordisk as part of its up to
- Novo Nordisk initiated the Phase 3 CLEOPATTRA clinical trial evaluating coramitug for ATTR-CM (NCT07207811)
- Novo Nordisk will present Phase 2 results during a late-breaking session at the American Heart Association Scientific Sessions on November 10, 2025
- Expect to earn a clinical milestone when prespecified enrollment criteria are met in ongoing Phase 3 clinical trial by Novo Nordisk
BMS-986446 (formerly PRX005), a potential best-in-class antibody for the treatment of Alzheimer’s disease that specifically targets a key epitope within the microtubule binding region (MTBR) of tau, a protein implicated in the causal pathophysiology of Alzheimer’s disease.
- Bristol Myers Squibb is conducting the Phase 2 TargetTau-1 clinical trial in approximately 310 patients with early Alzheimer’s disease; primary completion expected in 1H 2027 (NCT06268886)
- Bristol Myers Squibb is also conducting a Phase 1 open-label single-dose clinical trial to assess a subcutaneous administration; primary completion expected in 2H 2025 (NCT06955741)
-
BMS-986446 granted Fast Track designation by
U.S. FDA as a treatment for Alzheimer’s disease
PRX019, a potential treatment of neurodegenerative diseases in development in collaboration with Bristol Myers Squibb.
- Bristol Myers Squibb obtained the exclusive global license for PRX019 in 2024
- Prothena is conducting a Phase 1 first-in-human clinical trial to evaluate the safety, tolerability, immunogenicity, and pharmacokinetics of single ascending and multiple doses in healthy adults with completion expected in 2026
- Potential to earn a clinical milestone by end of 2026 should Bristol Myers Squibb decide to further develop PRX019
Upcoming Scientific and Investor Conferences
Novo Nordisk to present Phase 2 results for coramitug in a late-breaking session at the American Heart Association Scientific Sessions on November 10, 2025 in
- Title: Primary results from the phase 2 randomized, placebo controlled, blinded trial of the monoclonal antibody coramitug in transthyretin amyloid cardiomyopathy (ATTR-CM)
Prothena poster presentation on a TDP-43 CYTOPE®, a proprietary modality enabling cytosolic delivery of macromolecules for precision targeting of intracellular disease targets, in an ALS mouse model at Neuroscience 2025 annual meeting organized by Society for Neuroscience (SfN) on November 19, 2025 in
- Title: Treatment with a cell-internalizing antibody targeting pTDP43 reduces intraneuronal pathology in a mouse model of ALS
Members of the senior management team will present and participate in investor meetings at the following upcoming investor conferences:
-
Piper Sandler 37th Annual Healthcare Conference on Wednesday, December 3, 2025; fireside chat at 1:00 p.m. ET in
New York, NY -
8th Annual Evercore Healthcare Conference on Thursday, December 4, 2025; fireside chat at 10:50 a.m. ET in
Miami, FL
Third Quarter and First Nine Months of 2025 Financial Results
For the third quarter and first nine months of 2025, Prothena reported net loss of
Prothena reported total revenue of
Research and development (R&D) expenses totaled
General and administrative (G&A) expenses totaled
Total non-cash share-based compensation expense was
As of September 30, 2025, Prothena had
As of October 31, 2025, Prothena had approximately 53.8 million ordinary shares outstanding.
2025 Financial Guidance
The Company continues to expect its full year net cash used in operating and investing activities to be
Share Redemption Program
Prothena will convene an Extraordinary General Meeting (“EGM”) of shareholders on November 19, 2025 to vote on a proposal to approve a reduction in Prothena’s share capital to create distributable reserves, subject to confirmation by the Irish High Court, to support a potential share redemption program. The Board of Directors is seeking shareholder approval of such a proposal to create flexibility to potentially return capital to shareholders via a share redemption program through open market purchases or other permissible means in 2026. Any such program would be subject to the discretion of the Board of Directors and Prothena’s then-current financial condition.
About Prothena
Prothena Corporation plc is a late-stage clinical biotechnology company with expertise in protein dysregulation and a pipeline of investigational therapeutics with the potential to change the course of devastating neurodegenerative and rare peripheral amyloid diseases. Fueled by its deep scientific expertise built over decades of research, Prothena is advancing a pipeline of therapeutic candidates for a number of indications and novel targets for which its ability to integrate scientific insights around neurological dysfunction and the biology of misfolded proteins can be leveraged. Prothena’s pipeline includes both wholly-owned and partnered programs being developed for the potential treatment of diseases including ATTR amyloidosis with cardiomyopathy, Alzheimer’s disease, Parkinson’s disease and a number of other neurodegenerative diseases. For more information, please visit the Company’s website at www.prothena.com and follow the Company on X (formerly Twitter) @ProthenaCorp.
Forward-Looking Statements
This press release contains forward-looking statements. These statements relate to, among other things, the sufficiency of our cash position to fund advancement of a broad pipeline and completion of our ongoing clinical trials; the continued advancement of our discovery, preclinical, and clinical pipeline, and expected milestones in 2025, 2026, 2027, and beyond; the treatment potential, designs, proposed mechanisms of action, and potential administration of prasinezumab, coramitug, BMS-986446, and PRX019; plans for ongoing and future clinical trials of prasinezumab, coramitug, BMS-986446, and PRX019; the expected timing of reporting data from pre-clinical studies and clinical trials, including data from Novo Nordisk’s Phase 2 clinical trial evaluating coramitug on November 10, 2025 and our TDP-43 CYTOPE® program on November 19, 2025; projections regarding peak sales and patient population for prasinezumab; timing of and amounts we may receive under our collaborations with Novo Nordisk and Bristol Myers Squibb; our anticipated net cash burn from operating and investing activities for 2025 and expected cash balance at the end of 2025; our estimated net loss and non-cash share-based compensation expense for 2025; and the potential and ability to return capital to shareholders via a share redemption program or other permissible means if shareholders approve a reduction in share capital to create distributable reserves. These statements are based on estimates, projections and assumptions that may prove not to be accurate, and actual results could differ materially from those anticipated due to known and unknown risks, uncertainties and other factors, including but not limited to uncertainties related to the completion of operational and financial closing procedures, audit adjustments and other developments that may arise that would require adjustments to the preliminary financial results included in this press release, as well as those described in the “Risk Factors” sections of our Quarterly Report on Form 10-Q to be filed with the Securities and Exchange Commission (SEC) on November 6, 2025, and discussions of potential risks, uncertainties, and other important factors in our subsequent filings with the SEC. We undertake 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 our expectations.
PROTHENA CORPORATION PLC CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (unaudited - amounts in thousands except per share data) |
||||||||||||||||
|
|
Three Months Ended September 30, |
|
Nine Months Ended September 30, |
||||||||||||
|
|
2025 |
|
2024 |
|
2025 |
|
2024 |
||||||||
Collaboration revenue |
|
$ |
2,415 |
|
|
$ |
970 |
|
|
$ |
9,613 |
|
|
$ |
132,984 |
|
Revenue from license and intellectual property |
|
|
— |
|
|
|
— |
|
|
|
50 |
|
|
|
50 |
|
Total revenue |
|
|
2,415 |
|
|
|
970 |
|
|
|
9,663 |
|
|
|
133,034 |
|
Operating expenses: |
|
|
|
|
|
|
|
|
||||||||
Research and development |
|
|
28,938 |
|
|
|
50,723 |
|
|
|
120,266 |
|
|
|
172,347 |
|
General and administrative |
|
|
13,238 |
|
|
|
16,760 |
|
|
|
46,746 |
|
|
|
50,351 |
|
Restructuring costs |
|
|
479 |
|
|
|
— |
|
|
|
33,088 |
|
|
|
— |
|
Total operating expenses |
|
|
42,655 |
|
|
|
67,483 |
|
|
|
200,100 |
|
|
|
222,698 |
|
Loss from operations |
|
|
(40,240 |
) |
|
|
(66,513 |
) |
|
|
(190,437 |
) |
|
|
(89,664 |
) |
Other income, net |
|
|
3,328 |
|
|
|
6,677 |
|
|
|
11,187 |
|
|
|
20,235 |
|
Loss before income taxes |
|
|
(36,912 |
) |
|
|
(59,836 |
) |
|
|
(179,250 |
) |
|
|
(69,429 |
) |
Provision for (benefit from) income taxes |
|
|
(371 |
) |
|
|
(835 |
) |
|
|
43,253 |
|
|
|
(5,075 |
) |
Net loss |
|
$ |
(36,541 |
) |
|
$ |
(59,001 |
) |
|
$ |
(222,503 |
) |
|
$ |
(64,354 |
) |
Basic and diluted net loss per ordinary share |
|
$ |
(0.68 |
) |
|
$ |
(1.10 |
) |
|
$ |
(4.13 |
) |
|
$ |
(1.20 |
) |
Shares used to compute basic and diluted net loss per share |
|
|
53,830 |
|
|
|
53,790 |
|
|
|
53,828 |
|
|
|
53,757 |
|
PROTHENA CORPORATION PLC CONDENSED CONSOLIDATED BALANCE SHEETS (unaudited - amounts in thousands) |
|||||||
|
September 30, |
|
December 31, |
||||
|
2025 |
|
2024 |
||||
Assets |
|
|
|
||||
Cash and cash equivalents |
$ |
330,843 |
|
$ |
471,388 |
||
Prepaid expenses and other current assets |
|
9,131 |
|
|
|
14,024 |
|
Total current assets |
|
339,974 |
|
|
|
485,412 |
|
Property and equipment, net |
|
2,463 |
|
|
|
3,081 |
|
Operating lease right-of-use assets |
|
8,849 |
|
|
|
10,708 |
|
Restricted cash, non-current |
|
860 |
|
|
|
860 |
|
Other non-current assets |
|
482 |
|
|
|
47,047 |
|
Total non-current assets |
|
12,654 |
|
|
|
61,696 |
|
Total assets |
$ |
352,628 |
|
|
$ |
547,108 |
|
Liabilities and Shareholders’ Equity |
|
|
|
||||
Accrued research and development |
$ |
9,544 |
|
|
$ |
13,428 |
|
Deferred revenue, current |
|
2,685 |
|
|
|
8,850 |
|
Restructuring liability |
|
17,614 |
|
|
|
— |
|
Lease liability, current |
|
2,879 |
|
|
|
2,610 |
|
Other current liabilities |
|
18,714 |
|
|
|
23,613 |
|
Total current liabilities |
|
51,436 |
|
|
|
48,501 |
|
Deferred revenue, non-current |
|
— |
|
|
|
3,448 |
|
Lease liability, non-current |
|
6,203 |
|
|
|
8,233 |
|
Total non-current liabilities |
|
6,203 |
|
|
|
11,681 |
|
Total liabilities |
|
57,639 |
|
|
|
60,182 |
|
Total shareholders’ equity |
|
294,989 |
|
|
|
486,926 |
|
Total liabilities and shareholders’ equity |
$ |
352,628 |
|
|
$ |
547,108 |
|
View source version on businesswire.com: https://www.businesswire.com/news/home/20251106884802/en/
Mark Johnson, CFA, Vice President, Investor Relations
650-837-8550
IR@prothena.com
Media@prothena.com
Source: Prothena Corporation plc
