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ProthenaPRTA -1.32%74 Cash-to-Debt is 41.22 as of Jun. 2026, which is 31% above its 10-year median of 31.41. GuruFocus rates PRTA with a GF Score™ of 74/100 and a GF Value™ of $12.78 (Possible Value Trap). The stock has 2 warning signs investors should review. Among 1,395 Biotechnology companies, Prothena ranks better than 69.39% on this metric.
Cash to Debt Ratio measures the financial strength of a company. It is calculated as a company's cash, cash equivalents, and marketable securities divide by its debt. Prothena's cash to debt ratio for the quarter that ended in Jun. 2026 was 41.22.
If Cash to Debt ratio is greater than 1, the company can pay off its debt using the cash in hand. Here we can see, Prothenacould pay off its debt using the cash in hand for the quarter that ended in Jun. 2026.
(1) Note: An indication of "No Debt" does not necessarily mean that the company has no debt obligations; it could be due to missing data in the quarterly or annual report. Use caution when interpreting this information.
The historical rank and industry rank for Prothena's Cash-to-Debt or its related term are showing as below:
PRTA'
s Cash-to-Debt Range Over the Past 10 Years
Min: 7.54 Med: 31.41 Max: 191.16
Current: 41.22
During the past 13 years, Prothena's highest Cash to Debt Ratio was 191.16. The lowest was 7.54. And the median was 31.41.
PRTA's Cash-to-Debt is ranked better than 69.39% of 1395
companies
in the Biotechnology industry
Industry Median: 7.17
vs PRTA: 41.22
If Cash to Debt ratio is greater than 1, the company can pay off its debt using the cash in hand. If it is smaller than 1, it means the company has more debt than the cash in hands. In this case, it is important to look the the company's Interest Coverage. Ben Graham requires that a company must have an Interest Coverage of at least 5.
Prothena Cash-to-Debt Related Terms
Prothena Cash-to-Debt Historical Data
* Premium members only.
The historical data trend for Prothena's Cash-to-Debt can be seen below:
* For Operating Data section: All numbers are indicated by the unit behind each term and all currency related amount are in USD. * For other sections: All numbers are in millions except for per share data, ratio, and percentage. All currency related amount are indicated in the company's associated stock exchange currency.
Note: An indication of "No Debt" does not necessarily mean that the company has no debt obligations; it could be due to missing data in the quarterly or annual report. Use caution when interpreting this information.
For the Biotechnology subindustry, Prothena's Cash-to-Debt, along with its competitors' market caps and Cash-to-Debt data, can be viewed below:
* Competitive companies are chosen from companies within the same industry, with headquarter located in same country, with closest market capitalization; x-axis shows the market cap, and y-axis shows the term value; the bigger the dot, the larger the market cap. Note that "N/A" values will not show up in the chart.
Prothena Cash-to-Debt vs Biotechnology Industry
For the Biotechnology industry and Healthcare sector, Prothena's Cash-to-Debt distribution charts can be found below:
* The bar in red indicates where Prothena's Cash-to-Debt falls into.
Prothena's Cash to Debt Ratio for the fiscal year that ended in Dec. 2025 is calculated as:
Prothena had no debt (1).
Prothena's Cash to Debt Ratio for the quarter that ended in Jun. 2026 is calculated as:
Prothena had no debt (1).
* For Operating Data section: All numbers are indicated by the unit behind each term and all currency related amount are in USD. * For other sections: All numbers are in millions except for per share data, ratio, and percentage. All currency related amount are indicated in the company's associated stock exchange currency.
Prothena (PRTA) has a Cash-to-Debt of 41.22 as of Jun. 2026. This is 31% above median its historical median of 31.41. Over the past decade, Prothena's Cash-to-Debt has ranged from 7.54 to 191.16. According to the industry distribution chart, Prothena ranks #427 out of 1395 companies in the Biotechnology industry, placing it in the top 30.6%.
Is Prothena's Cash-to-Debt too high?
Prothena's current Cash-to-Debt of 41.22 is 31% above median its 10-year median of 31.41. Over the past 10 years, this metric has ranged from a low of 7.54 to a high of 191.16. The Biotechnology industry median Cash-to-Debt is 7.17. Prothena's value of 41.22 is 474.9% above this industry median. Based on the distribution chart, Prothena ranks #427 out of 1395 companies in the Biotechnology industry, which is above the industry midpoint. Overall, Prothena has a GF Score™ of 74/100 and is considered Possible Value Trap, reflecting its overall financial health beyond just this single metric.
How does Prothena's Cash-to-Debt compare to EVMN and EDIT?
According to the Biotechnology industry distribution chart, Prothena ranks #427 out of 1395 companies for Cash-to-Debt. This puts Prothena in the upper half of its industry. The industry median Cash-to-Debt is 7.17. Prothena's value of 41.22 is 474.9% above this benchmark. Historically, Prothena's own Cash-to-Debt has ranged from 7.54 to 191.16 over the past decade. While the company's 10-year median is 31.41 vs. the industry median of 7.17, Prothena has consistently been above the industry average. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good Cash-to-Debt for a Biotechnology company?
The median Cash-to-Debt among Biotechnology companies is 7.17, based on 1,395 companies in the industry. Companies in the top quartile (top 25%) have a Cash-to-Debt significantly above this median, while those in the bottom quartile fall well below. However, Cash-to-Debt should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Prothena's current Cash-to-Debt of 41.22 is 474.9% above the industry median. Use the industry distribution chart on this page to see where any company falls relative to its peers.
What does a high Cash-to-Debt mean?
A high Cash-to-Debt can signal that a stock is expensive relative to its fundamentals. For the Biotechnology industry, the median Cash-to-Debt is 7.17 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Prothena's current Cash-to-Debt is 41.22, which is 31% above median its own 10-year median of 31.41. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Prothena stock overvalued right now?
Based on GuruFocus' analysis, Prothena (PRTA) is currently considered Possible Value Trap. The stock's GF Value™ is $12.78, compared to a current price of $8.24 — trading 35.5% below its estimated fair value. The current Cash-to-Debt is 41.22, which is 31% above median its 10-year median of 31.41 and 474.9% above the Biotechnology industry median of 7.17. Prothena's overall GF Score™ is 74/100 with 2 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is Cash-to-Debt calculated?
Cash-to-Debt is calculated from a company's financial statements. For Prothena (PRTA), the current Cash-to-Debt is 41.22 as of Jun. 2026. GuruFocus calculates this using data sourced from SEC filings and annual reports. See the calculation section and 30-year financial data on this page for the full breakdown.
Is Prothena (PRTA) Overvalued in 2026?
Based on GuruFocus' analysis, Prothena stock appears to be undervalued.
The current stock price of $8.24 is trading 35.5% below its estimated GF Value™ of $12.78.
GuruFocus considers Prothena to be Possible Value Trap.
Key valuation signals for PRTA:
Cash-to-Debt: 41.22 (31% above median its 10-year median of 31.41)
GF Value™: $12.78 vs. price of $8.24 (35.5% below fair value)
Industry Position: 474.9% above the Biotechnology median (#427 of 1395)
No single metric tells the full story. See the PRTA stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
Prothena Corp PLC is a late-stage clinical biotechnology company that focuses on protein dysregulation and a pipeline of investigational therapeutics with the potential to change the course of devastating neurodegenerative and rare and peripheral amyloid diseases. Prothena is developing and applying its proprietary CYTOPE technology to target a broad spectrum of intracellular disease pathways in the brain and periphery. The company's pipeline includes both wholly-owned and partnered programs like Prasinezumab, Coramitug (PRX004), BMS-986446 (PRX005), PRX019, TDP-43 CYTOPE, and PRX012-TfR, being developed for the potential treatment of Parkinson's disease, ATTR amyloidosis with cardiomyopathy, Alzheimer's disease, Amyotrophic lateral sclerosis (ALS), and other neurodegenerative diseases.
74GF Score
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