PTIX (Protagenic Therapeutics) Cyclically Adjusted Book per Share: $64.35 (As of Dec. 2025)

Author: Vera Yuan Vera Yuan
Vera Yuan
Vera Yuan
Director of Data and Quant Analytics at GuruFocus
Focused on building reliable datasets, financial models, and research tools for value-minded investors. Committed to turning complex data into practical guidance for value-investing and long-term wealth.
Reviewed by: Charlie Tian Charlie Tian
Charlie Tian
Charlie Tian
Founder & CEO of GuruFocus
Dr. Charlie Tian is the founder and CEO of GuruFocus.com, a leading global investment research platform established in 2004. With a Ph.D. in physics, Dr. Tian transitioned from science to finance, applying a data-driven, disciplined approach to value investing.

PTIX Protagenic Therapeutics Inc PTIX
22 GF Score
Price $0.18
! 2 Warning Signs
View Full Analysis

What is Protagenic Therapeutics Cyclically Adjusted Book per Share?

Protagenic Therapeutics PTIX +8.02% 22 Cyclically Adjusted Book per Share is $64.35 as of Dec. 2025. GuruFocus rates PTIX with a GF Score™ of 22/100. The stock has 2 warning signs investors should review.

E10 is a concept invented by Prof. Robert Shiller, who uses E10 for his Shiller PE Ratio calculation. E10 is the average of the inflation adjusted earnings of a company over the past 10 years. The similar calculation is applied by GuruFocus to calculate the Cyclically Adjusted Book per Share and the Cyclically Adjusted PB Ratio. The Cyclically Adjusted Book per Share is the average of the inflation adjusted Book Value per Share of a company over the past 10 years.

Protagenic Therapeutics's adjusted book value per share for the three months ended in Dec. 2025 was $-1.237. Add all the adjusted book value per share for the past 10 years together and divide the count will get our Cyclically Adjusted Book per Share, which is $64.35 for the trailing ten years ended in Dec. 2025.

During the past 12 months, Protagenic Therapeutics's average Cyclically Adjusted Book Growth Rate was -8.10% per year. During the past 3 years, the average Cyclically Adjusted Book Growth Rate was -7.00% per year. During the past 5 years, the average Cyclically Adjusted Book Growth Rate was -9.00% per year. Please click Growth Rate Calculation Example (GuruFocus) to see how GuruFocus calculates Wal-Mart Stores Inc (WMT)'s revenue growth rate. You can apply the same method to get the Cyclically Adjusted Book Growth Rate using Cyclically Adjusted Book per Share data.

During the past 13 years, the highest 3-Year average Cyclically Adjusted Book Growth Rate of Protagenic Therapeutics was -6.60% per year. The lowest was -39.80% per year. And the median was -14.75% per year.

As of today (2026-08-01), Protagenic Therapeutics's current stock price is $0.18. Protagenic Therapeutics's Cyclically Adjusted Book per Share for the quarter that ended in Dec. 2025 was $64.35. Protagenic Therapeutics's Cyclically Adjusted PB Ratio of today is 0.00.


Protagenic Therapeutics  (OTCPK:PTIX) Cyclically Adjusted Book per Share Explanation

If a company grows much fast than inflation, Cyclically Adjusted Book per Share may underestimate the company's equity. Cyclically Adjusted PB Ratio can seem to be too high even the actual PB Ratio is low.

For the Cyclically Adjusted PB Ratio, the book value of the past 10 years are inflation-adjusted and averaged. The result is used for P/B calculation. Since it looks at the average over the last 10 years, the Cyclically Adjusted PB Ratio is also called CAPB Ratio.

The Shiller PE Ratio was first used by professor Robert Shiller. He uses E10 for his Shiller PE Ratio calculation. E10 is the average of the inflation adjusted earnings per share of a company over the past 10 years. The similar calculation is applied by GuruFocus to calculate the Cyclically Adjusted PB Ratio. The Cyclically Adjusted Book per Share is the average of the inflation adjusted book value per share of a company over the past 10 years.

Protagenic Therapeutics's Cyclically Adjusted PB Ratio of today is calculated as

Cyclically Adjusted PB Ratio=Share Price/Cyclically Adjusted Book per Share
=0.18/64.35
=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.


Be Aware

Cyclically Adjusted PB Ratio works better for cyclical companies. It gives you a better idea on the company's real book value.


Protagenic Therapeutics Cyclically Adjusted Book per Share Related Terms


Protagenic Therapeutics Cyclically Adjusted Book per Share Historical Data

* Premium members only.

The historical data trend for Protagenic Therapeutics's Cyclically Adjusted Book per Share 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.

Protagenic Therapeutics Cyclically Adjusted Book per Share Chart

Protagenic Therapeutics Annual Data
Trend Jun15 Dec16 Dec17 Dec18 Dec19 Dec20 Dec21 Dec22 Dec23 Dec24
Cyclically Adjusted Book per Share
Get a 7-Day Free Trial Premium Member Only Premium Member Only 93.63 86.89 82.59 76.40 70.00

Protagenic Therapeutics Quarterly Data
Mar21 Jun21 Sep21 Dec21 Mar22 Jun22 Sep22 Dec22 Mar23 Jun23 Sep23 Dec23 Mar24 Jun24 Sep24 Dec24 Mar25 Jun25 Sep25 Dec25
Cyclically Adjusted Book per Share 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 70.00 68.96 67.61 66.23 64.35

PTIX vs CERO, CYTOF, CARM: Cyclically Adjusted Book per Share Comparison

For the Biotechnology subindustry, Protagenic 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.


Protagenic Therapeutics Cyclically Adjusted PB Ratio vs Biotechnology Industry

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

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


PTIX
22GF Score
Protagenic Therapeutics Inc PTIX
Cyclically Adjusted Book per Share is just one metric. See GF Score™, valuation, warning signs, and more.
View Full Analysis

Protagenic Therapeutics Cyclically Adjusted Book per Share Calculation

E10 is a concept invented by Prof. Robert Shiller, who uses E10 for his Shiller PE Ratio calculation. E10 is the average of the inflation adjusted earnings of a company over the past 10 years. The similar calculation is applied by GuruFocus to calculate the Cyclically Adjusted Book per Share and the Cyclically Adjusted PB Ratio. The Cyclically Adjusted Book per Share is the average of the inflation adjusted Book Value per Share of a company over the past 10 years.

What is Cyclically Adjusted Book per Share? How do we calculate Cyclically Adjusted Book per Share?

Cyclically Adjusted Book per Share is the average of the inflation adjusted Book Value per Share of a company over the past 10 years. Let's use an example to explain.

If we want to calculate the Cyclically Adjusted Book per Share of Wal-Mart (WMT) for Dec. 31, 2010, we need to have the inflation data and the book value per share from 2001 through 2010.

We adjusted the 2001 book value per share data with the total inflation from 2001 through 2010 to the equivalent book value in 2010. If the total inflation from 2001 to 2010 is 40%, and Wal-Mart's book value is $1 a share in 2001, then the 2001's equivalent book value in 2010 is $1.4 a share. If Wal-Mart's book value is $1 again in 2002, and the total inflation from 2002 through 2010 is 35%, then the equivalent 2002 book value in 2010 is $1.35. So on and so forth, you get the equivalent book value per share of past 10 years. Then you add them together and divided the sum by the count to get 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.

For example, Protagenic Therapeutics's adjusted Book Value per Share data for the three months ended in Dec. 2025 was:

Adj_Book= Book Value per Share /CPI of Dec. 2025 (Change)*Current CPI (Dec. 2025)
=-1.237/324.0540*324.0540
=-1.237

Current CPI (Dec. 2025) = 324.0540.

Protagenic Therapeutics Quarterly Data

Book Value per Share CPI Adj_Book
201603 0.000 238.132 0.000
201606 1,593.500 241.018 2,142.496
201609 19.858 241.428 26.654
201612 13.536 241.432 18.168
201703 11.896 243.801 15.812
201706 10.257 244.955 13.569
201709 9.197 246.819 12.075
201712 6.661 246.524 8.756
201803 5.273 249.554 6.847
201806 3.060 251.989 3.935
201809 1.765 252.439 2.266
201812 -1.153 251.233 -1.487
201903 -1.978 254.202 -2.522
201906 -2.071 256.143 -2.620
201909 -1.989 256.759 -2.510
201912 -3.464 256.974 -4.368
202003 -3.202 258.115 -4.020
202006 -4.077 257.797 -5.125
202009 -5.519 260.280 -6.871
202012 -6.216 260.474 -7.733
202103 -10.492 264.877 -12.836
202106 37.234 271.696 44.409
202109 34.228 274.310 40.435
202112 32.384 278.802 37.640
202203 28.312 287.504 31.911
202206 26.725 296.311 29.227
202209 23.890 296.808 26.083
202212 22.388 296.797 24.444
202303 20.757 301.836 22.285
202306 17.521 305.109 18.609
202309 13.440 307.789 14.150
202312 11.571 306.746 12.224
202403 6.726 312.332 6.978
202406 2.486 314.175 2.564
202409 2.096 315.301 2.154
202412 1.959 315.605 2.011
202503 -0.164 319.799 -0.166
202506 -2.150 322.561 -2.160
202509 -2.429 324.800 -2.423
202512 -1.237 324.054 -1.237

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

What does a Cyclically Adjusted Book per Share of $64.35 mean?
Protagenic Therapeutics (PTIX) has a Cyclically Adjusted Book per Share of $64.35 as of Dec. 2025. Cyclically adjusted book value per share represents the company's inflation-adjusted book value per share over a 10-year period. View historical data on Protagenic Therapeutics and its competitors.
Is Protagenic Therapeutics' Cyclically Adjusted Book per Share too high?
Protagenic Therapeutics' current Cyclically Adjusted Book per Share is $64.35. Overall, Protagenic Therapeutics has a GF Score™ of 22/100, reflecting its overall financial health beyond just this single metric.
How does Protagenic Therapeutics' Cyclically Adjusted Book per Share compare to CERO and CYTOF?
Protagenic Therapeutics' Cyclically Adjusted Book per Share of $64.35 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 Cyclically Adjusted Book per Share for a Biotechnology company?
A good Cyclically Adjusted Book per Share depends on the Biotechnology industry context. However, Cyclically Adjusted Book per Share 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 Cyclically Adjusted Book per Share mean?
A high Cyclically Adjusted Book per Share can signal that a stock is expensive relative to its fundamentals. Cyclically adjusted book value per share represents the company's inflation-adjusted book value per share over a 10-year period. View historical data on Protagenic Therapeutics and its competitors. Protagenic Therapeutics's current Cyclically Adjusted Book per Share is $64.35. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Protagenic Therapeutics stock overvalued right now?
Protagenic Therapeutics (PTIX) has a current Cyclically Adjusted Book per Share of $64.35. The current Cyclically Adjusted Book per Share is $64.35. Protagenic Therapeutics' overall GF Score™ is 22/100 with 2 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is Cyclically Adjusted Book per Share calculated?
Cyclically Adjusted Book per Share is calculated from a company's financial statements. For Protagenic Therapeutics (PTIX), the current Cyclically Adjusted Book per Share is $64.35 as of Dec. 2025. 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.

Protagenic Therapeutics Business Description

Address 149 Fifth Avenue, Suite 500, New York, NY, USA, 10010
Protagenic Therapeutics Inc is a biopharmaceutical company focused on the discovery and development of therapeutics to treat stress-related neuropsychiatric and mood disorders. It provides treatments for mood, anxiety, depression, and neurodegenerative disorders by using peptide-based and brain-active therapeutics. The company's main compound, PT00114, is a synthetic form of Teneurin Carboxy-terminal Associated Peptide, an endogenous brain signaling peptide that can dampen overactive stress responses. It has also created a portfolio of novel neuropeptides that are in various stages of development and preclinical evaluation for the treatment of mood disorders.
22GF Score

Get the complete analysis for PTIX

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

$0.18
Price