PRTA Stock — Prothena Corporation plc: Cash, EV, Pipeline

What they do

The Company’s pipeline includes both wholly-owned and partnered programs being developed for the potential treatment of diseases including Parkinson’s disease, ATTR amyloidosis with cardiomyopathy, Alzheimer’s disease, Amyotrophic lateral sclerosis (ALS) and a number of other neurodegenerative diseases.

Source: 10-K FY2025 via SEC EDGAR

Share price

$8.59

Market cap

$441.1M

Cash

$271.4M

Enterprise value

$169.7M

Balance sheet

Cash	$271.4M
Debt	$0.0M
Net cash	$271.4M
Enterprise value	$169.7M
Basic shares	51.4M shares
Fully diluted shares	63.1M shares
Fully diluted market cap	$542.3M
Cash per share	$5.28
Quarterly burn	$25.0M
Cash runway	10.8 quarters

Cash figures as of 2026-09-30. Database snapshot: 2026-11-11.

Share structure

Common

51.3M

Pre-funded warrants

0.0M

Options

11.8M

RSUs

0.0M

Warrants

0.0M

Converts

0.0M

Conv preferred

0.0M

ESPP reserve

—

FDSO

63.1M

Cap table as of 2026-06-30.

Price history

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Upcoming catalysts

No upcoming catalysts on file for this company.

Full readout calendar →

Pipeline assets

Moponetug

Stage not disclosed · Active Modality: antibody

Aliases BMS-986446, PRX005

Target tau

Partnerships Bristol Myers Squibb: U.S. License Agreement (July 30, 2021) and Global License Agreement (July 5, 2023) granting BMS an exclusive license to develop, manufacture, and commercialize antibodies targeting the tau/moponetug collaboration target

Status note Antibody program targeting tau; BMS holds the exclusive U.S. and global licenses. Clinical stage not stated in the excerpts.

PRX019

Stage not disclosed · Active Modality: antibody

Target undisclosed

Partnerships Bristol Myers Squibb: Global License Agreement (May 24, 2024) granting BMS an exclusive license to develop, manufacture, and commercialize products targeting the undisclosed/PRX019 collaboration target

Status note Antibody program against an undisclosed target (PRX019 collaboration target); BMS holds the exclusive global license. Clinical stage not stated in the excerpts.

Coramitug

Stage not disclosed · Active Modality: antibody

Aliases PRX004

Target TTR

Partnerships Novo Nordisk: collaboration; Prothena recognized a development milestone payment from Novo Nordisk in the six months ended June 30, 2026

Indications

ATTR amyloidosis (Stage not disclosed)

Status note Antibody for ATTR amyloidosis partnered with Novo Nordisk; Prothena is eligible for development/commercialization milestones and royalties if Novo Nordisk advances products containing coramitug or derivatives. Clinical stage not stated.

Per-asset detail extracted from the 10-Q filed 2026-08-06. Fields the filing does not state are marked "not disclosed" rather than filled from other sources.

No lead program on file for this company.

Active clinical trials

Trial	Phase	Status	Role	Sponsor	BP	Condition(s)	Mgmt guide
NCT07174310	Phase 3	Recruiting	Collaborator	Hoffmann-La Roche	—	Parkinson's Disease	—
NCT03100149	Phase 2	Active, not recruiting	Collaborator	Hoffmann-La Roche	—	Parkinson's Disease	—
NCT04777331	Phase 2	Active, not recruiting	Collaborator	Hoffmann-La Roche	—	Parkinsons Disease	—

Sponsor-matched active trials from ClinicalTrials.gov (0 as sponsor, 3 as collaborator); "Sponsor" = company is the lead sponsor, "Collaborator" = company is a collaborator. The BP column flags big-pharma involvement as lead sponsor or collaborator (excluding the company itself). The Mgmt guide column shows what management guided for readout timing when a guided program matches the trial (hover for the quote, click for the source). Trial listings are not a company pipeline slide.

View all 3 active trials for Hoffmann-La Roche on ClinicalTrials.gov

Specialist fund holders

Tracked specialist funds: ADAR1 Capital Management, Aisling Capital, Ally Bridge Group, Avoro Capital Advisors, BVF Partners, Baker Bros. Advisors, Boxer Capital, Braidwell LP, Casdin Capital, Cormorant Asset Management, DAFNA Capital, Deerfield Management, EcoR1 Capital, Frazier Life Sciences, Great Point Partners, Ikarian Capital, Logos Global Management, OrbiMed Advisors, Perceptive Advisors, RA Capital Management, RTW Investments, Sphera Biotech, Stonepine Capital, Tang Capital Partners, Vivo Capital.

Fund	Shares	Q/Q change	% of portfolio	Filing
ADAR1 Capital Management	1,554,535	-26,908	0.72%	2026-08-14

Specialist-fund positions from 13F filings. Q/Q change is vs the prior quarter's filing; % of portfolio is the fund's own reported portfolio weight.

Latest news

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PRTA — Prothena Corporation plc ☆

What they do

Balance sheet

Share structure

Price history

Upcoming catalysts

Pipeline assets

Active clinical trials

Specialist fund holders

Latest news

PRTA — Prothena Corporation plc