SPRO (Spero Therapeutics) Tax Rate %: 0.00% (As of Mar. 2026)


SPRO Spero Therapeutics Inc SPRO
55 GF Score
Price $2.21
GF Value $1.06
Valuation Significantly Overvalued
! 4 Warning Signs
View Full Analysis

What is Spero Therapeutics Tax Rate %?

Spero Therapeutics SPRO -2.64% 55 Tax Rate % is 0.00% as of Mar. 2026. GuruFocus rates SPRO with a GF Score™ of 55/100 and a GF Value™ of $1.06 (Significantly Overvalued). The stock has 4 warning signs investors should review.

Tax Rate % is calculated as Tax Expense divided by its Pre-Tax Income. Spero Therapeutics's Tax Expense for the three months ended in Mar. 2026 was $0.00 Mil. Spero Therapeutics's Pre-Tax Income for the three months ended in Mar. 2026 was $-7.20 Mil. Therefore, Spero Therapeutics's Tax Rate % for the quarter that ended in Mar. 2026 was 0.00%.

Spero Therapeutics Tax Rate % Related Terms

Spero Therapeutics Tax Rate % Historical Data

* Premium members only.

The historical data trend for Spero Therapeutics's Tax Rate % 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.

Spero Therapeutics Tax Rate % Chart

Spero Therapeutics Annual Data
Trend Dec16 Dec17 Dec18 Dec19 Dec20 Dec21 Dec22 Dec23 Dec24 Dec25
Tax Rate %
Get a 7-Day Free Trial Premium Member Only Premium Member Only 0.00 0.00 10.23 0.00 2.95

Spero Therapeutics Quarterly Data
Jun21 Sep21 Dec21 Mar22 Jun22 Sep22 Dec22 Mar23 Jun23 Sep23 Dec23 Mar24 Jun24 Sep24 Dec24 Mar25 Jun25 Sep25 Dec25 Mar26
Tax Rate % Get a 7-Day Free Trial Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only 0.00 0.00 0.00 0.82 0.00
SPRO
55GF Score
Spero Therapeutics Inc SPRO
Tax Rate % is just one metric. See GF Score™, valuation, warning signs, and more.
View Full Analysis

Spero Therapeutics Tax Rate % Calculation

Tax Rate % is the ratio of tax expense divided by pretax income, usually presented in percent.

Spero Therapeutics's Tax Rate % for the fiscal year that ended in Dec. 2025 is calculated as

Tax Rate %=Tax Expense (A: Dec. 2025 )/Pre-Tax Income (A: Dec. 2025 )
=0.261/8.833
=2.95 %

Spero Therapeutics's Tax Rate % for the quarter that ended in Mar. 2026 is calculated as

Tax Rate %=Tax Expense (Q: Mar. 2026 )/Pre-Tax Income (Q: Mar. 2026 )
=0/-7.203
=0.00 %

* 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.

Frequently Asked Questions Learn more about Tax Rate % →
What does a Tax Rate % of 0.00% mean?
Spero Therapeutics (SPRO) has a Tax Rate % of 0.00% as of Mar. 2026.
Is Spero Therapeutics' Tax Rate % too high?
Spero Therapeutics' current Tax Rate % is 0.00%. 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' Tax Rate % compare to VXRT and ADCT?
Spero Therapeutics' Tax Rate % of 0.00% 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 Tax Rate % for a Biotechnology company?
A good Tax Rate % depends on the Biotechnology industry context. However, Tax Rate % 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 Tax Rate % mean?
A high Tax Rate % can signal that a stock is expensive relative to its fundamentals. Spero Therapeutics's current Tax Rate % is 0.00%. 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 $2.21 — trading 108.5% above its estimated fair value. The current Tax Rate % is 0.00%. 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 Tax Rate % calculated?
Tax Rate % is calculated from a company's financial statements. For Spero Therapeutics (SPRO), the current Tax Rate % is 0.00% as of Mar. 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 $2.21 is trading 108.5% above its estimated GF Value™ of $1.06. GuruFocus considers Spero Therapeutics to be Significantly Overvalued.

Key valuation signals for SPRO:

  • Tax Rate %: 0.00%
  • GF Value™: $1.06 vs. price of $2.21 (108.5% above fair value)
  • GF Score™: 55/100 with 4 warning signs

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 Business Description

Other Exchanges 2HA:Germany
Address 675 Massachusetts Avenue, 14th Floor, Cambridge, MA, USA, 02139
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

Get the complete analysis for SPRO

Tax Rate % is just one metric. See GF Value™, 30-year financials, guru trades, warning signs, and more.

$2.21
Price
$1.06
GF Value