Prothena (PRTA) AI Stock Analysis

• Market Cap: $514.08M
• Dividend Yield: N/A
• Average Volume (3M): 732.47K
• Price to Earnings (P/E): ―
• Beta (1Y): 0.88
• Revenue Growth: -91.16%
• EPS Growth: -112.24%
• Country: US
• Employees: 163
• Sector: Healthcare
• Sector Strength: 45
• Industry: Biotechnology
• EPS (TTM): -0.68
• Shares Outstanding: 53,829,983
• 10 Day Avg. Volume: 686,318
• 30 Day Avg. Volume: 732,465
• PEG Ratio: 0.34
• Price to Book (P/B): 1.53
• Price to Sales (P/S): 5.51
• P/FCF Ratio: -4.95
• Enterprise Value/Market Cap: -0.07
• Enterprise Value/Revenue: -2.96
• Enterprise Value/Gross Profit: 2.04
• Enterprise Value/Ebitda: 0.16
• 1Y Price Target: $20.33
• Price Target Upside: 112.88% Upside
• Rating Consensus: Moderate Buy
• Number of Analyst Covering: 6
• EPS Forecast (FY): N/A
• Revenue Forecast (FY): N/A

• Rating: 50 Neutral
• Price Target: $10.50 ▲(9.95% Upside)

Prothena's overall stock score is primarily impacted by its financial challenges, including negative profitability and cash flows. While technical indicators show some positive momentum, the valuation remains a significant concern due to ongoing losses. The recent corporate event provides a positive outlook for financial flexibility, but strategic improvements are necessary for long-term growth.

Positive Factors

Innovative Drug Delivery

The development of CYTOPE, enabling cytosolic delivery of macromolecules, represents a significant advancement in targeting previously undruggable intracellular disease targets, potentially enhancing Prothena's competitive edge in neurodegenerative disease therapies.

Capital Reduction Approval

The approval of a capital reduction proposal is a positive development, potentially enhancing Prothena's financial flexibility and shareholder value by creating distributable reserves, which can be used for strategic investments or debt reduction.

Strategic Alliances

Prothena's strategic alliances with larger pharmaceutical firms enhance its financial resources and distribution network access, supporting long-term revenue generation and market reach, crucial for a clinical-stage biotech company.

Negative Factors

Negative Profitability

Persistent negative profitability metrics indicate ongoing financial challenges, limiting Prothena's ability to reinvest in R&D and potentially affecting long-term growth and sustainability unless addressed.

Cash Flow Challenges

Negative cash flows constrain Prothena's operational and growth capabilities, necessitating improved cash generation strategies to ensure financial stability and fund future development projects.

Revenue Decline

A significant decline in revenue growth reflects challenges in achieving development milestones or product commercialization, potentially impacting Prothena's ability to sustain operations and invest in new initiatives.

Prothena Business Overview & Revenue Model

Company Description

Prothena Corporation plc, a late-stage clinical company, focuses on discovery and development of novel therapies for life-threatening diseases in the United States. The company is involved in developing Birtamimab, an investigational humanized antibody that is in Phase III clinical trial for the treatment of AL amyloidosis; Prasinezumab, a humanized monoclonal antibody, which is in Phase IIb clinical trial for the treatment of Parkinson's disease; PRX004 that completed Phase I clinical trial for the treatment of Transthyretin amyloidosis; and PRX005, which is in Phase I clinical trial for the treatment of Alzheimer's disease. Its discovery and preclinical programs include PRX012 for the treatment of Alzheimer's disease; and dual Aß-Tau vaccine for the treatment and prevention of Alzheimer's disease. Prothena Corporation plc has a license, development, and commercialization agreement with F. Hoffmann-La Roche Ltd. and Hoffmann-La Roche Inc. to develop and commercialize antibodies that target alpha-synuclein; and a collaboration agreement with Bristol-Myers Squibb to develop antibodies. The company was founded in 2012 and is based in Dublin, Ireland.

How the Company Makes Money

Prothena generates revenue primarily through collaborations and partnerships with pharmaceutical companies, which often involve upfront payments, milestone payments based on the achievement of specific development goals, and royalties on sales of approved products. The company may also receive funding from government grants and research institutions for specific projects. Prothena's strategic alliances with larger pharmaceutical firms can significantly enhance its financial resources and provide access to broader distribution networks, thereby contributing to its overall earnings. Additionally, any successful commercialization of its therapeutic candidates can lead to substantial revenues from product sales and licensing agreements.

Prothena Financial Statement Overview

Summary

Prothena faces significant financial challenges, with declining revenue, negative profit margins, and cash flow difficulties. Despite a low debt-to-equity ratio indicating limited leverage, the company struggles with profitability and cash flow issues, which are critical for its financial health.

Income Statement

Prothena's income statement reveals significant challenges, with declining revenue and negative profit margins. The TTM data shows a sharp revenue decline of over 92%, and the net profit margin is deeply negative at -29.29%. The company has struggled with profitability, as evidenced by negative EBIT and EBITDA margins. Despite past revenue growth, recent trends indicate financial instability.

Balance Sheet

The balance sheet shows a low debt-to-equity ratio of 0.03, indicating limited leverage and potential financial stability. However, the return on equity is negative, reflecting ongoing losses. The equity ratio is not provided, but the company's equity position appears relatively strong compared to its debt, which is a positive aspect.

Cash Flow

Cash flow analysis indicates negative operating and free cash flows, with a slight improvement in free cash flow growth. The operating cash flow to net income ratio is negative, highlighting cash flow challenges. The free cash flow to net income ratio is close to 1, suggesting that cash flow issues are aligned with net income losses.

Breakdown	TTM	Dec 2024	Dec 2023	Dec 2022	Dec 2021	Dec 2020
Income Statement
Total Revenue	11.79M	135.16M	91.37M	53.91M	200.58M	853.00K
Gross Profit	-17.15M	135.16M	91.37M	53.91M	200.58M	-74.03M
EBITDA	-217.76M	-153.67M	-190.11M	-130.81M	73.09M	-111.22M
Net Income	-280.46M	-122.31M	-147.03M	-116.95M	66.97M	-111.14M
Balance Sheet
Total Assets	352.63M	547.11M	696.38M	758.03M	609.37M	332.98M
Cash, Cash Equivalents and Short-Term Investments	330.84M	471.39M	618.83M	710.41M	579.09M	295.38M
Total Debt	9.08M	10.84M	11.84M	6.47M	12.33M	17.84M
Total Liabilities	57.64M	60.18M	135.02M	135.99M	143.32M	148.97M
Stockholders Equity	294.99M	486.93M	561.37M	622.04M	466.04M	184.01M
Cash Flow
Free Cash Flow	-188.22M	-150.35M	-136.72M	-109.28M	92.03M	-80.56M
Operating Cash Flow	-188.04M	-150.05M	-133.91M	-108.82M	92.61M	-80.36M
Investing Cash Flow	-181.00K	-298.00K	-2.77M	-464.00K	-575.00K	-196.00K
Financing Cash Flow	-198.00K	1.55M	45.10M	241.46M	190.33M	215.00K

Prothena Technical Analysis

• Technical Analysis Sentiment: Negative
• Last Price: 9.55
• 50DMA: Negative
• 100DMA: Negative
• 200DMA: Positive
• MACD: Positive
• RSI: Neutral
• STOCH: Neutral

Evaluating momentum and price trends is crucial in stock analysis to make informed investment decisions. For PRTA, the sentiment is Negative. The current price of 9.55 is below the 20-day moving average (MA) of 9.97, below the 50-day MA of 10.19, and above the 200-day MA of 8.69, indicating a neutral trend. The MACD of -0.24 indicates Positive momentum. The RSI at 44.48 is Neutral, neither overbought nor oversold. The STOCH value of 44.60 is Neutral, not indicating any strong overbought or oversold conditions. Overall, these indicators collectively point to a Negative sentiment for PRTA.

Prothena Peers Comparison

Name	Overall Rating	Market Cap	P/E Ratio	ROE	Dividend Yield	Revenue Growth	EPS Growth
XOMA	58 Neutral	$329.27M	35.67	16.22%	―	118.02%	―
ZVRA	57 Neutral	$504.43M	14.20	34.81%	―	240.47%	―
ALMS	56 Neutral	$1.02B	-2.53	-66.88%	―	―	13.80%
Sector *	51 Neutral	$7.86B	-0.30	-43.30%	2.27%	22.53%	-2.21%
PRTA	50 Neutral	$514.08M	-1.83	-67.63%	―	-91.16%	-112.24%
CRVS	50 Neutral	$575.05M	-14.40	-35.82%	―	―	79.27%
LXRX	48 Neutral	$417.91M	-6.07	-45.92%	―	1255.21%	74.58%

Prothena Corporate Events

Prothena Board Member Paula Cobb Resigns

On December 10, 2025, Paula Cobb announced her resignation from Prothena Corporation plc’s Board of Directors, effective December 31, 2025. Her departure is not due to any disagreements with the company’s operations, policies, or practices.

Prothena Shareholders Approve Capital Reduction Proposal

On November 19, 2025, Prothena Corporation held an extraordinary general meeting where shareholders approved a proposal to reduce the company’s capital to create distributable reserves. This decision is expected to impact the company’s financial flexibility and potentially enhance shareholder value.