[8-K] Spero Therapeutics, Inc. Reports Material Event

Rhea-AI Filing Summary

Spero Therapeutics’ Form 8-K details the voting results of its 12 June 2025 Annual Meeting. A quorum of 40,015,633 shares (71.57%) of the 55.9 million shares outstanding was present.

Board elections: Class II directors Frank E. Thomas, Patrick Vink M.D., and Esther Rajavelu were re-elected through 2028, each receiving roughly 25.7 million votes for and 0.4-2.9 million votes withheld; 13.8 million broker non-votes were recorded.

Auditor ratification: PricewaterhouseCoopers LLP was confirmed as independent auditor for FY 2025 with an overwhelming 39.8 million ‘for’ versus 175 k ‘against’.

Say-on-pay: Executive compensation received shareholder support—25.18 million ‘for’ (96.0%) against 0.64 million ‘against’.

Equity plan amendment: Shareholders approved increasing the 2017 Stock Incentive Plan by 3 million additional shares (22.97 million for / 3.15 million against). This authorizes extra equity that may dilute existing holders once issued but expands flexibility to attract and retain talent.

No financial performance data, earnings guidance, or major strategic transactions were disclosed; the filing is limited to governance and compensation matters.

Positive

• Board continuity preserved with re-election of all Class II directors, supporting strategic consistency.
• Strong shareholder support for auditor (99.6% in favour) and executive compensation (96% in favour) signals investor confidence in oversight and pay practices.

Negative

• Potential dilution from authorizing 3 million additional shares (≈5.4% of outstanding) under the stock incentive plan.
• Noticeable dissent of 12% against the equity plan signals some shareholder concern over dilution and compensation structure.

Insights

Corporate Governance Expert

TL;DR – Routine AGM items passed; governance status quo maintained.

The meeting reaffirmed board composition and auditor selection, indicating stability in Spero’s oversight structure. Turnout above 70% reflects reasonable shareholder engagement. All proposals cleared majority thresholds, though the stock plan increase saw ~12% opposition, a typical level for dilution-sensitive items. Overall, governance risk profile unchanged; no red flags emerge.

Portfolio Manager

TL;DR – Share grant expansion adds mild dilution risk; otherwise neutral.

The 3 million-share addition (≈5.4% of current float) could dilute future EPS, a modest negative for valuation if fully issued. Yet approval suggests investors value management retention amid development-stage biotech challenges. With no operational updates, the filing is largely procedural, hence limited immediate market impact.

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of The Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): June 12, 2025

SPERO THERAPEUTICS, INC.

(Exact name of registrant as specified in its charter)

Delaware		001-38266		46-4590683
(State or other jurisdiction of incorporation)		(Commission File Number)		(I.R.S. Employer Identification No.)

675 Massachusetts Avenue, 14th Floor
Cambridge, Massachusetts				02139
(Address of principal executive offices)				(Zip Code)

Registrant’s telephone number, including area code (857) 242-1600

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class		Trading Symbol(s)		Name of each exchange on which registered
Common Stock, $0.001 par value		SPRO		The Nasdaq Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 5.02 Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers

At the 2025 Annual Meeting of Stockholders (the “Annual Meeting”) of Spero Therapeutics, Inc. (the “Company”) held on June 12, 2025, the Company’s stockholders approved an amendment to the Company’s 2017 Stock Incentive Plan, as amended (the “2017 Plan”) to increase the total number of shares of the Company’s common stock authorized for issuance under the 2017 Plan by 3,000,000 shares.

A detailed summary of the material features of the 2017 Plan, as amended, is set forth in the Company’s definitive proxy statement (the “Proxy Statement”) for its Annual Meeting filed with the Securities and Exchange Commission on April 28, 2025, which summary is incorporated herein by reference.

Item 5.07 Submission of Matters to a Vote of Stockholders

On June 12, 2025, the Company held its Annual Meeting. Of the 55,910,641 shares of common stock issued and outstanding and eligible to vote as of the record date of April 21, 2025, a quorum of 40,015,633 shares, or approximately 71.57% of the outstanding shares, were present in person or by proxy.

The following actions were taken at the Annual Meeting:

1. The following nominees were reelected to serve on the Company’s board of directors as Class II directors until the Company’s 2028 annual meeting of stockholders, based on the following votes:

Name		Votes For		Votes Withheld		Broker Non-Votes
Frank E. Thomas		25,722,977		449,223		13,843,433
Patrick Vink, M.D.		23,247,371		2,924,829		13,843,433
Esther Rajavelu		25,678,198		494,002		13,843,433

2. The selection of PricewaterhouseCoopers LLP as the Company’s independent registered public accounting firm for the fiscal year ending December 31, 2025 was ratified, based on the following votes:

Votes For		Votes Against		Votes Abstained		Broker Non-Votes
39,837,359		174,980		3,294		N/A

3. 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
25,178,672		638,744		354,784		13,843,433

4. The amendment to the 2017 Plan to increase the total number of shares of common stock authorized for issuance thereunder by 3,000,000 shares, was approved, based on the following votes:

Votes For		Votes Against		Votes Abstained		Broker Non-Votes
22,965,487		3,154,609		52,104		13,843,433

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Date: June 18, 2025				SPERO THERAPEUTICS, INC.
				By:		/s/ Esther Rajavelu
						Esther Rajavelu
						Chief Executive Officer, Chief Financial Officer and Chief Business Officer

FAQ

How many additional shares did SPRO add to its 2017 Stock Incentive Plan?

Shareholders approved an increase of 3,000,000 shares under the plan.

What was the shareholder turnout at Spero Therapeutics' 2025 AGM?

A quorum of 40,015,633 shares, or 71.57% of outstanding stock, was present.

Were Spero Therapeutics' Class II directors re-elected?

Yes. Frank E. Thomas, Patrick Vink M.D., and Esther Rajavelu were each re-elected through 2028.

Did shareholders ratify PricewaterhouseCoopers as auditor for FY 2025?

Yes. 39,837,359 votes supported PwC, with only 174,980 against.

How did shareholders vote on executive compensation (say-on-pay)?

The advisory vote passed with 25,178,672 votes for and 638,744 against.