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The 3-Year Sortino Ratio measures the additional return that an investor receives per unit of the downside risk over the past three years. As of today (2026-08-04), Spero Therapeutics's 3-Year Sortino Ratio is 2.16.
Spero Therapeutics (NAS:SPRO) 3-Year Sortino Ratio Explanation
The 3-Year Sortino Ratio inidicates the risk-adjusted return of an investment over the past three year. It is calculated as the annualized result of the average three-year monthly excess returns divided by the standard deviation of negative returns in the three-year period. The monthly excess return is the monthly investment return minus the monthly risk-free rate (typically the 10-year Treasury Constant Maturity Rate). If the risk-free rate for a specific region is not available, U.S. data is used by default.
Differnt from the Sharpe Ratio that penalizes both upside and downside volatility equally, the Sortino Ratio penalizes only those returns falling below a user-specified target or required rate of return. The expected returns here is set to the risk-free rate as well.
Spero Therapeutics 3-Year Sortino Ratio Related Terms
SPRO vs ACRV, BSEM, RNTX: 3-Year Sortino Ratio Comparison
For the Biotechnology subindustry, Spero Therapeutics's 3-Year Sortino Ratio, along with its competitors' market caps and 3-Year Sortino Ratio 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.
Spero Therapeutics 3-Year Sortino Ratio vs Biotechnology Industry
For the Biotechnology industry and Healthcare sector, Spero Therapeutics's 3-Year Sortino Ratio distribution charts can be found below:
* The bar in red indicates where Spero Therapeutics's 3-Year Sortino Ratio falls into.
Spero Therapeutics 3-Year Sortino Ratio Calculation
The 3-Year Sortino Ratio measures the risk-adjusted return of an investment asset or portfolio in the last three year, focusing specifically on downside risk rather than total risk. A stock / portfolio's 3-Year Sortino Ratio can be calculated by dividing the difference between the three-year average monthly returns of the investment and the risk-free rate, by the standard deviation of the downside risks over the past three year.
A downside risk is a potential loss from the asset or investment. The Downside risk here is measured by the downside deviation, which is the standard deviation of negative returns.
Spero Therapeutics (SPRO) has a 3-Year Sortino Ratio of 2.16 as of Aug. 04, 2026. 3-Year Sortino Ratio measures the additional return that an investor receives per unit of the downside risk over the past three years. View historical data for Spero Therapeutics and its competitors.
Is Spero Therapeutics' 3-Year Sortino Ratio too high?
Spero Therapeutics' current 3-Year Sortino Ratio is 2.16. Overall, Spero Therapeutics has a GF Score™ of 66/100 and is considered Fairly Valued, reflecting its overall financial health beyond just this single metric.
How does Spero Therapeutics' 3-Year Sortino Ratio compare to ACRV and BSEM?
Spero Therapeutics' 3-Year Sortino Ratio of 2.16 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 3-Year Sortino Ratio for a Biotechnology company?
A good 3-Year Sortino Ratio depends on the Biotechnology industry context. However, 3-Year Sortino Ratio 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 3-Year Sortino Ratio mean?
A high 3-Year Sortino Ratio can signal that a stock is expensive relative to its fundamentals. 3-Year Sortino Ratio measures the additional return that an investor receives per unit of the downside risk over the past three years. View historical data for Spero Therapeutics and its competitors. Spero Therapeutics's current 3-Year Sortino Ratio is 2.16. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Spero Therapeutics stock overvalued right now?
Based on GuruFocus' analysis, Spero Therapeutics (SPRO) is currently considered Fairly Valued. The stock's GF Value™ is $1.05, compared to a current price of $1.16 — trading 10.5% above its estimated fair value. The current 3-Year Sortino Ratio is 2.16. Spero Therapeutics' overall GF Score™ is 66/100 with 5 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is 3-Year Sortino Ratio calculated?
3-Year Sortino Ratio is calculated from a company's financial statements. For Spero Therapeutics (SPRO), the current 3-Year Sortino Ratio is 2.16 as of Aug. 04, 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 Spero Therapeutics (SPRO) Overvalued in 2026?
Based on GuruFocus' analysis, Spero Therapeutics stock appears to be overvalued.
The current stock price of $1.16 is trading 10.5% above its estimated GF Value™ of $1.05.
GuruFocus considers Spero Therapeutics to be Fairly Valued.
Key valuation signals for SPRO:
3-Year Sortino Ratio: 2.16
GF Value™: $1.05 vs. price of $1.16 (10.5% above fair value)
No single metric tells the full story. See the SPRO stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
Spero Therapeutics Inc is a clinical-stage biopharmaceutical firm. It focuses on identifying, developing, and commercializing novel treatments for MDR (Multi-drug-resistant) bacterial infections and rare diseases. The company's product candidate, tebipenem pivoxil hydrobromide or tebipenem HBr, is designed to be an oral carbapenem-class antibiotic for use in adults to treat MDR Gram-negative infections. It is also developing SPR720, a novel oral antibiotic designed for the treatment of a rare, orphan disease caused by pulmonary non-tuberculous mycobacterial infections, or NTM disease. It is also focused on SPR206, a next-generation polymyxin investigational product candidate being developed as an IV-administered medicine to treat MDR Gram-negative infections in the hospital.
66GF Score
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