Spero Therapeutics (MEX:SPRO) Cyclically Adjusted PB Ratio: (As of Aug. 22, 2026)

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MEX:SPRO Spero Therapeutics Inc MEX:SPRO
40 GF Score
Price MXN20.74
GF Value MXN13.54
Valuation Significantly Overvalued
! 2 Warning Signs
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What is Spero Therapeutics Cyclically Adjusted PB Ratio?

Note: If the price history is too short, we do not calculate current Cyclically Adjusted PB Ratio for this stock. All the historical data is shown as the company's primary share's data instead.

Shiller PE for Stocks: The True Measure of Stock Valuation


Spero Therapeutics  (MEX:SPRO) Cyclically Adjusted PB Ratio Explanation

Compared with the regular PB Ratio, which works poorly for cyclical businesses, the Cyclically Adjusted PB Ratio smoothed out the fluctuations of book value during business cycles. Therefore it is more accurate in reflecting the valuation of the company.

If a company has consistent business performance, the Cyclically Adjusted PB Ratio should give similar results to regular PB Ratio.


Spero Therapeutics Cyclically Adjusted PB Ratio Related Terms


Spero Therapeutics Cyclically Adjusted PB Ratio Historical Data

* Premium members only.

The historical data trend for Spero Therapeutics's Cyclically Adjusted PB Ratio 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 Cyclically Adjusted PB Ratio Chart

Spero Therapeutics Annual Data
Trend Dec16 Dec17 Dec18 Dec19 Dec20 Dec21 Dec22 Dec23 Dec24 Dec25
Cyclically Adjusted PB Ratio
Get a 7-Day Free Trial Premium Member Only Premium Member Only 0.00 0.00 0.00 0.00 0.00

Spero Therapeutics Quarterly Data
Sep21 Dec21 Mar22 Jun22 Sep22 Dec22 Mar23 Jun23 Sep23 Dec23 Mar24 Jun24 Sep24 Dec24 Mar25 Jun25 Sep25 Dec25 Mar26 Jun26
Cyclically Adjusted PB Ratio 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 0.78 0.71

MEX:SPRO vs : Cyclically Adjusted PB Ratio Comparison

For the Biotechnology subindustry, Spero Therapeutics's Cyclically Adjusted PB Ratio, along with its competitors' market caps and Cyclically Adjusted PB 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 Cyclically Adjusted PB Ratio vs Biotechnology Industry

For the Biotechnology industry and Healthcare sector, Spero Therapeutics's Cyclically Adjusted PB Ratio distribution charts can be found below:

* The bar in red indicates where Spero Therapeutics's Cyclically Adjusted PB Ratio falls into.


MEX:SPRO
40GF Score
Spero Therapeutics Inc MEX:SPRO
Cyclically Adjusted PB Ratio is just one metric. See GF Score™, valuation, warning signs, and more.
View Full Analysis

Spero Therapeutics Cyclically Adjusted PB Ratio Calculation

Like the Shiller PE Ratio, the Cyclically Adjusted PB Ratio takes the Book Value per Share from the past 10 years, adjusts it for inflation, and then calculates the average. This average is then used for the P/B calculation. Because it considers this 10-year average, it's often referred to as the CAPB Ratio.

The Shiller PE Ratio was first used by professor Robert Shiller to measure the valuation of the overall market. The similar calculation is applied by GuruFocus to calculate the Cyclically Adjusted PB Ratio.

Spero Therapeutics's Cyclically Adjusted Book per Share for the quarter that ended in Jun. 2026 is calculated as:

For example, Spero Therapeutics's adjusted Book Value per Share data for the three months ended in Jun. 2026 was:

Adj_Book=Book Value per Share/CPI of Jun. 2026 (Change)*Current CPI (Jun. 2026)
=13.306/333.9520*333.9520
=13.306

Current CPI (Jun. 2026) = 333.9520.

Spero Therapeutics Quarterly Data

Book Value per Share CPI Adj_Book
201609 0.000 241.428 0.000
201612 -117.103 241.432 -161.978
201703 0.000 243.801 0.000
201706 86.981 244.955 118.583
201709 -111.334 246.819 -150.638
201712 115.634 246.524 156.643
201803 94.249 249.554 126.124
201806 89.265 251.989 118.300
201809 134.040 252.439 177.322
201812 127.723 251.233 169.776
201903 127.256 254.202 167.180
201906 118.848 256.143 154.951
201909 98.058 256.759 127.539
201912 73.780 256.974 95.881
202003 98.826 258.115 127.862
202006 82.464 257.797 106.824
202009 133.736 260.280 171.590
202012 95.836 260.474 122.871
202103 82.589 264.877 104.127
202106 60.539 271.696 74.411
202109 71.600 274.310 87.168
202112 56.017 278.802 67.098
202203 38.146 287.504 44.309
202206 21.913 296.311 24.697
202209 18.210 296.808 20.489
202212 30.313 296.797 34.108
202303 22.250 301.836 24.617
202306 17.865 305.109 19.554
202309 17.748 307.789 19.257
202312 33.511 306.746 36.483
202403 29.844 312.332 31.910
202406 27.332 314.175 29.053
202409 23.831 315.301 25.241
202412 17.636 315.605 18.661
202503 12.492 319.799 13.045
202506 11.033 322.561 11.423
202509 8.635 324.800 8.878
202512 15.501 324.054 15.974
202603 16.664 330.213 16.853
202606 13.306 333.952 13.306

Add all the adjusted book value per share together and divide the count will get our Cyclically Adjusted Book per Share.

Please note that we use the CPI data of the country/region where the company is headquartered. If the CPI data for that country/region is not available, then we will use the CPI data of the United States as default.

Is Spero Therapeutics (MEX:SPRO) Overvalued in 2026?

Based on GuruFocus' analysis, Spero Therapeutics stock appears to be overvalued. The current stock price of MXN20.74 is trading 53.2% above its estimated GF Value™ of MXN13.54. GuruFocus considers Spero Therapeutics to be Significantly Overvalued.

Key valuation signals for MEX:SPRO:

  • Cyclically Adjusted PB Ratio:
  • GF Value™: MXN13.54 vs. price of MXN20.74 (53.2% above fair value)
  • GF Score™: 40/100 with 2 warning signs

No single metric tells the full story. See the MEX:SPRO stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.


Spero Therapeutics Business Description

Comparable Companies
Other Exchanges SPRO:USA2HA: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.
40GF Score

Get the complete analysis for MEX:SPRO

Cyclically Adjusted PB Ratio is just one metric. See GF Value™, 30-year financials, guru trades, warning signs, and more.

MXN20.74
Price
MXN13.54
GF Value