The Relative Strength Index (RSI) is a momentum oscillator that measures the speed and change of price movements. The RSI is most typically used on a 14-day period, measured on a scale from 0 to 100. Traditionally, an asset is considered overbought or overvalued when the RSI is above 70 and oversold or undervalued when it is below 30. A shorter period RSI is more reactive to recent price changes, so it can show early signs of reversals. 9-Day RSI is sometimes used together with 14-Day RSI in a two period divergence strategy.
The Relative Strength Index (RSI), developed by J. Welles Wilder in his book “New Concepts in Technical Trading Systems.”, is a momentum oscillator that measures the speed and change of price movements. The RSI is most typically used on a 14-day period, measured on a scale from 0 to 100.
Traditionally, an asset is considered overbought or overvalued when the RSI is above 70 and oversold or undervalued when it is below 30. A RSI surpasses the 30 level indicates a bullish sign, when it slides below 70 level, it’s a bearish sign. This level can be adjusted depending on the security’s pattern and the market’s underlying trend. In an uptrend or bullish market, the RSI might range within a higher interval, investors could set the support level higher. If a downtrend or bearish market occurs, investors may need to lower the resistance level.
RSI can also be used in trading techniques to indicate the trading signal, such as Divergences and Swing Rejections. A shorter period RSI is more reactive to recent price changes, so it can show early signs of reversals. 9-Day RSI is sometimes used together with 14-Day RSI in a two period divergence strategy.
Spero Therapeutics 9-Day RSI Related Terms
SPRO vs ORMP, PLYX, HRTX: 9-Day RSI Comparison
For the Biotechnology subindustry, Spero Therapeutics's 9-Day RSI, along with its competitors' market caps and 9-Day RSI 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 9-Day RSI vs Biotechnology Industry
For the Biotechnology industry and Healthcare sector, Spero Therapeutics's 9-Day RSI distribution charts can be found below:
* The bar in red indicates where Spero Therapeutics's 9-Day RSI falls into.
* Note that the formula uses a positive value for the average loss.
* 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.
Spero Therapeutics (SPRO) has a 9-Day RSI of 42.67 as of Jun. 26, 2026. According to the industry distribution chart, Spero Therapeutics ranks #224 out of 1425 companies in the Biotechnology industry, placing it in the top 15.7%.
Is Spero Therapeutics' 9-Day RSI too high?
Spero Therapeutics' current 9-Day RSI is 42.67. The Biotechnology industry median 9-Day RSI is 45.00. Spero Therapeutics' value of 42.67 is 5.2% below this industry median. Based on the distribution chart, Spero Therapeutics ranks #224 out of 1425 companies in the Biotechnology industry, which is in the top quartile — a strong position relative to peers. Overall, Spero Therapeutics has a GF Score™ of 55/100 and is considered Significantly Overvalued, reflecting its overall financial health beyond just this single metric.
How does Spero Therapeutics' 9-Day RSI compare to ORMP and PLYX?
According to the Biotechnology industry distribution chart, Spero Therapeutics ranks #224 out of 1425 companies for 9-Day RSI. This places Spero Therapeutics in the top 16% of its industry — outperforming the majority of peers. The industry median 9-Day RSI is 45.00. Spero Therapeutics' value of 42.67 is 5.2% below this benchmark. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good 9-Day RSI for a Biotechnology company?
The median 9-Day RSI among Biotechnology companies is 45.00, based on 1,425 companies in the industry. Companies in the top quartile (top 25%) have a 9-Day RSI significantly above this median, while those in the bottom quartile fall well below. However, 9-Day RSI should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Spero Therapeutics's current 9-Day RSI of 42.67 is 5.2% below 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 9-Day RSI mean?
A high 9-Day RSI can signal that a stock is expensive relative to its fundamentals. For the Biotechnology industry, the median 9-Day RSI is 45.00 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Spero Therapeutics's current 9-Day RSI is 42.67. 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 Significantly Overvalued. The stock's GF Value™ is $1.06, compared to a current price of $2.26 — trading 113.2% above its estimated fair value. The current 9-Day RSI is 42.67 and 5.2% below the Biotechnology industry median of 45.00. Spero Therapeutics' overall GF Score™ is 55/100 with 4 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is 9-Day RSI calculated?
9-Day RSI is calculated from a company's financial statements. For Spero Therapeutics (SPRO), the current 9-Day RSI is 42.67 as of Jun. 26, 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 $2.26 is trading 113.2% above its estimated GF Value™ of $1.06.
GuruFocus considers Spero Therapeutics to be Significantly Overvalued.
Key valuation signals for SPRO:
9-Day RSI: 42.67
GF Value™: $1.06 vs. price of $2.26 (113.2% above fair value)
Industry Position: 5.2% below the Biotechnology median (#224 of 1425)
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.
55GF Score
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