Spero Therapeutics, Inc. — fact timeline

Spero Therapeutics, Inc. reported first quarter ended March 31, 2026 results: revenue Total revenue for the first quarter of 2026 was $0.3 million, net income Spero reported a net loss of $7.2 million for the first quarter of 2026, EPS diluted net loss per share of common stock of $0.13.

“Spero Therapeutics , Inc. (Nasdaq: SPRO), a clinical-stage biopharmaceutical company focused on identifying and developing novel treatments for rare diseases and diseases with high unmet need, today announced financial results for the first quarter ended March 31, 2026, and provided a business update.”

Spero Therapeutics, Inc. reported the year ended December 31, 2025 results: revenue $66.8 million, net income $8.6 million, EPS $0.15.

“fourth quarter of 2025 was primarily due to an increase in collaboration revenue from our agreements with GSK and Pfizer. Total revenue for the year ended December 31, 2025, was $66.8 million, compared to $48.0 million for the year ended December 31, 2024. The revenue increase for the year was primarily due to the aforementioned collaboration revenue related to our”

Spero Therapeutics, Inc. reported the fourth quarter and full year ended December 31, 2025 results: revenue $41.3 million, net income $31.5 million, EPS $0.53.

“diluted net gain per share of common stock of $0.15 and a diluted net loss per share of common stock of $(1.27), respectively. • Total revenue for the fourth quarter of 2025 was $41.3 million, compared to total revenue of $15.0 million for the fourth quarter of 2024. The revenue increase for the fourth quarter of 2025 was primarily due to an increase in collaboration”

Esther Rajavelu was appointed as President and Chief Executive Officer at Spero Therapeutics, Inc..

“On April 28, 2025, Spero Therapeutics, Inc. (the “Company”) announced that effective as of May 2, 2025 (the “Effective Date”), Esther Rajavelu will serve as the Company’s President and Chief Executive Officer.”

Spero Therapeutics, Inc. received a nasdaq deficiency notice notice regarding minimum bid price (rules 5450(a)(1)).

“otifying the Company that, for the preceding 30 consecutive trading days, the closing bid price of its common stock was below the $1.00 per share minimum bid price requirement for continued inclusion on the Nasdaq Global Market pursuant to Nasdaq Listing Rule 5450(a)(1) (the “Bid Price Requirement”). At this current time, this Notice has no effect on the listing of the Company’s common stock, which continues to trade on the Nasdaq Global Select Market (“Nasdaq GS”) under the symbol “SPRO”.”

Spero Therapeutics, Inc. announced a restructuring with charges of approximately $1.1 million affecting Company-wide (approximately 39%).

“The Company estimates that it will incur aggregate restructuring charges of approximately $1.1 million in cash expenditures in connection with the reduction in workforce related to severance pay and other related termination benefits.”

Spero Therapeutics, Inc. reported the first quarter ended March 31, 2024 results: revenue $9.3 million, net income net loss of $12.7 million, or ($0.24) per share of common stock, basic and diluted, EPS ($0.24) per share.

“net loss of $13.3 million, or ($0.25) per share of common stock, basic and diluted, for the first quarter ended March 31, 2023. • Total revenue for the first quarter of 2024 was $9.3 million, compared with total revenue of $2.1 million for the first quarter of 2023. The revenue increase for the first quarter of 2024 was primarily due to an increase in collaboration”

Spero Therapeutics, Inc. reported fourth quarter and full year ended December 31, 2023 results: net income Spero reported net income of $51.2 million for the fourth quarter and an overall net income of $22.8 million, for the ye, EPS $0.96 and $0.43.

“Spero reported net income of $51.2 million for the fourth quarter and an overall net income of $22.8 million, for the year ended December 31, 2023, or a diluted net income per share of common stock of $0.96 and $0.43, respectively.”

Tamara Joseph departed as Chief Legal Officer and Corporate Secretary at Spero Therapeutics, Inc..

“Tamara Joseph, the Chief Legal Officer and Corporate Secretary of Spero Therapeutics, Inc. (the “Company”), is stepping down from that position to pursue other interests, effective as of March 6, 2024 (the “Effective Date”).”

Spero Therapeutics, Inc. reported financial results for the third quarter ended September 30, 2023.

“On November 13, 2023, Spero Therapeutics, Inc. (the “Company”) issued a press release announcing its results for the third quarter ended September 30, 2023.”

Esther Rajavelu was appointed as Chief Financial Officer and Chief Business Officer at Spero Therapeutics, Inc..

“On October 30, 2023, the Board of Directors (the “Board”) of Spero Therapeutics, Inc. (the “Company”) appointed Esther Rajavelu as the Company’s Chief Financial Officer and Chief Business Officer.”

Spero Therapeutics, Inc.: Filed a Certificate of Correction to undo the previously filed Charter Amendment due to a tabulation error, restoring the charter to its prior state (effective 2023-10-16).

“On October 16, 2023, the Company filed the Certificate of Correction with the Delaware Secretary to undo the Charter Amendment.”

Spero Therapeutics, Inc. shareholders rejected Amend the Charter to reflect new Delaware law provisions regarding officer exculpation and to add a federal forum selection clause.

“The Charter Amendment Proposals did not receive the necessary stockholder votes and were not approved.”

Spero Therapeutics, Inc.: Certificate of Amendment filed to add officer exculpation provisions and a federal forum selection clause (effective 2023-10-06).

“On October 6, 2023, the Company filed a Certificate of Amendment to its Amended and Restated Certificate of Incorporation, as amended, with the Secretary of State of the State of Delaware to reflect new Delaware law provisions regarding officer exculpation and to add a federal forum selection clause”

Spero Therapeutics, Inc. shareholders approved Amendment to the 2017 Plan at the 2023-10-05 meeting.

“The amendment to the 2017 Plan was approved, based on the following votes: Votes For Votes Against Votes Abstained Broker Non-Votes 19,839,570 1,661,568 26,821 12,586,113”

Spero Therapeutics, Inc. shareholders approved Amendment to Amended and Restated Certificate of Incorporation to add a federal forum selection clause at the 2023-10-05 meeting.

“The amendment to the Company’s Amended and Restated Certificate of Incorporation, as amended, to add a federal forum selection clause was approved, based on the following votes: Votes For Votes Against Votes Abstained Broker Non-Votes 21,336,574 168,709 22,676 12,586,113”

Spero Therapeutics, Inc. shareholders approved Amendment to Amended and Restated Certificate of Incorporation to reflect new Delaware law provisions regarding officer exculpation at the 2023-10-05 meeting.

“The amendment to the Company’s Amended and Restated Certificate of Incorporation, as amended, to reflect new Delaware law provisions regarding officer exculpation was approved, based on the following votes: Votes For Votes Against Votes Abstained Broker Non-Votes 20,915,583 578,765 33,611 12,586,113”

Spero Therapeutics, Inc. shareholders voted on Advisory vote on frequency of holding an advisory vote on executive compensation (one year selected) at the 2023-10-05 meeting.

“The advisory vote of the frequency of holding an advisory vote on compensation of the Company’s named executive officers was ratified as one year, based on the following votes: 1 Year 2 Years 3 Years Votes Abstained Broker Non-Votes 20,741,824 35,775 171,220 579,140 12,586,113”

Spero Therapeutics, Inc. shareholders approved Advisory vote on compensation of named executive officers at the 2023-10-05 meeting.

“The advisory vote of the compensation of the Company’s named executive officers, as described in the Proxy Statement, was approved, based on the following votes: Votes For Votes Against Votes Abstained Broker Non-Votes 20,123,647 1,145,027 259,285 12,586,113”

Spero Therapeutics, Inc. shareholders approved Ratification of PricewaterhouseCoopers LLP as independent registered public accounting firm for fiscal year ending December 31, 2023 at the 2023-10-05 meeting.

“The selection of PricewaterhouseCoopers LLP as the Company’s independent registered public accounting firm for the fiscal year ending December 31, 2023 was ratified, based on the following votes: Votes For Votes Against Votes Abstained Broker Non-Votes 33,997,793 62,995 53,284 0”

Spero Therapeutics, Inc. shareholders approved Election of three Class III directors to serve until 2026 annual meeting at the 2023-10-05 meeting.

“The following nominees were reelected to serve on the Company’s board of directors as Class III directors until the Company’s 2026 annual meeting of stockholders, based on the following votes: Name Votes For Votes Withheld Broker Non-Votes Milind Deshpande, Ph.D. 18,831,596 2,696,363 12,586,113 Ankit Mahadevia, M.D. 21,412,529 115,430 12,586,113 Kathleen Tregoning 20,945,300 582,659 12,586,113”

Spero Therapeutics, Inc. reported second quarter ended June 30, 2023 results: revenue $2.7 million, net income net loss of $11.9 million, EPS $0.23 per basic and diluted share.

“Spero reported a net loss for the second quarter ended June 30, 2023 of $11.9 million or $0.23 per basic and diluted share of common stock, compared to a net loss of $28.7 million or $0.87 per basic and diluted share of common stock reported for the same period in 2022. Total revenues for the second quarter of 2023 were $2.7 million”

Stephen J. DiPalma was appointed as Interim Chief Financial Officer and Treasurer at Spero Therapeutics, Inc..

“Stephen J. DiPalma to be the Company’s Interim Chief Financial Officer and Treasurer to succeed Mr. Shukla”

Satyavrat Shukla was appointed as Chief Executive Officer and President at Spero Therapeutics, Inc..

“Satyavrat Shukla, the Company’s current Chief Financial Officer and Treasurer, was appointed by the Board to serve as Chief Executive Officer and President of the Company and as a member of the Board”

Ankit Mahadevia was appointed as Chairman of the Board at Spero Therapeutics, Inc..

“Dr. Mahadevia will serve as a consultant to the Company and will continue to serve as a member of the Company’s Board of Directors (the “Board”) and will assume the role of Chairman of the Board”

Ankit Mahadevia departed as Chief Executive Officer and President at Spero Therapeutics, Inc..

“Ankit Mahadevia, M.D., the Company’s Chief Executive Officer and President, determined to step down from that role, effective as of August 1, 2023”

Spero Therapeutics, Inc. reported financial results for the first quarter ended March 31, 2023.

“On May 11, 2023, Spero Therapeutics, Inc. (the “Company”) issued a press release announcing its results for the first quarter ended March 31, 2023.”

Spero Therapeutics, Inc. reported financial results for the fourth quarter and full year ended December 31, 2022.

“On March 30, 2023, Spero Therapeutics, Inc. (the "Company") issued a press release announcing its results for the fourth quarter and full year ended December 31, 2022.”

Timothy Keutzer was appointed as Chief Operating Officer at Spero Therapeutics, Inc..

“On January 30, 2023, the Board of Directors (the “Board”) of Spero Therapeutics, Inc. (the “Company”) appointed Timothy Keutzer as the Company’s Chief Operating Officer, effective as of February 1, 2023”

Spero Therapeutics, Inc. reported financial results for the quarter ended September 30, 2022.

“On November 14, 2022, Spero Therapeutics, Inc. (the “Company”) issued a press release announcing its results for the quarter ended September 30, 2022.”

David Melnick departed as Chief Medical Officer at Spero Therapeutics, Inc..

“Chief Medical Officer Effective as of the Effective Date, David Melnick, M.D. will separate from the Company as its Chief Medical Officer pursuant to the Restructuring.”

Cristina Larkin departed as Chief Operating Officer at Spero Therapeutics, Inc..

“Chief Operating Officer Effective as of July 2, 2022 (the "Effective Date"), Cristina Larkin will separate from the Company as its Chief Operating Officer pursuant to the Restructuring.”

Kathleen Tregoning was appointed as Director at Spero Therapeutics, Inc..

“On October 11, 2021, the Board, upon the recommendation of the Nominating and Corporate Governance Committee of the Board, appointed Kathleen Tregoning to the Board, effective as of October 11, 2021, to fill the vacancy created by Dr. Formela’s resignation.”

Jean-François Formela resigned as Director at Spero Therapeutics, Inc..

“On October 11, 2021, Jean-François Formela, M.D. notified the Board of Directors (the “Board”) of Spero Therapeutics, Inc. (the “Company”) of his resignation from the Board and the Compensation Committee and Nominating and Corporate Governance Committee of the Board, effective as of October 11, 2021.”