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6-Month Price Index is an intermediate-term momentum that shows the price change relative to 6-month ago. It’s calculated by current share price divided by share price 6-months ago. As of today (2026-08-21), Prothena's 6-Month Price Index is 1.00.
Prothena (NAS:PRTA) 6-Month Price Index Explanation
Price Index (PI) also called momentum. Strategies involving Price Index are also known as momentum strategies as they allow investors to profit from a company’s stock price. 6-Month Price Index is an intermediate-term momentum that shows the price change relative to 6-month ago.
The investment strategy for momentum investors is to buy winners and sell losers. That is, buy stocks that performed well and sell stocks that performed poorly in the past.
Prothena 6-Month Price Index Related Terms
PRTA vs KYTX, QTTB, RZLT: 6-Month Price Index Comparison
For the Biotechnology subindustry, Prothena's 6-Month Price Index, along with its competitors' market caps and 6-Month Price Index 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 (NAS:PRTA) 6-Month Price Index Calculation
6-Month Price Index is calculated as following:
6-Month Price Index
=
Current Share Price
/
Share Price 6-Months Ago
* 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 6-Month Price Index of 1.00 as of Aug. 21, 2026. 6-Month Price Index is an intermediate-term momentum that shows the price change relative to 6-month ago. View historical data on Prothena and its competitors.
Is Prothena's 6-Month Price Index too high?
Prothena's current 6-Month Price Index is 1.00. 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 6-Month Price Index compare to KYTX and QTTB?
Prothena's 6-Month Price Index of 1.00 can be compared against companies in the Biotechnology industry. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good 6-Month Price Index for a Biotechnology company?
A good 6-Month Price Index depends on the Biotechnology industry context. However, 6-Month Price Index should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Use the industry distribution chart on this page to see where any company falls relative to its peers.
What does a high 6-Month Price Index mean?
A high 6-Month Price Index can signal that a stock is expensive relative to its fundamentals. 6-Month Price Index is an intermediate-term momentum that shows the price change relative to 6-month ago. View historical data on Prothena and its competitors. Prothena's current 6-Month Price Index is 1.00. 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 $12.95, compared to a current price of $9.03 — trading 30.3% below its estimated fair value. The current 6-Month Price Index is 1.00. 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 6-Month Price Index calculated?
6-Month Price Index is calculated from a company's financial statements. For Prothena (PRTA), the current 6-Month Price Index is 1.00 as of Aug. 21, 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 $9.03 is trading 30.3% below its estimated GF Value™ of $12.95.
GuruFocus considers Prothena to be Possible Value Trap.
Key valuation signals for PRTA:
6-Month Price Index: 1.00
GF Value™: $12.95 vs. price of $9.03 (30.3% below fair value)
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
Get the complete analysis for PRTA
6-Month Price Index is just one metric. See GF Value™, 30-year financials, guru trades, warning signs, and more.
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