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Spero Therapeutics entered an exclusive license with Innovent Biologics for SP001, a third-generation Fc-silent anti-CD40L monoclonal antibody. Spero receives a worldwide license outside mainland China, Hong Kong, Macau and Taiwan and grants Innovent exclusive rights in that territory. Spero will pay Innovent a $35.0 million upfront fee, up to approximately $1.05 billion in development, regulatory and commercial milestones, and tiered royalties on net sales, and has agreed to file a U.S. IND for a Licensed Product within 12 months and use commercially reasonable efforts to develop and commercialize at least one indication in major markets.
On July 8, 2026, Spero also completed a non-recourse royalty financing tied to tebipenem HBr (Utebzi) economics under its GSK license. A special-purpose subsidiary issued senior secured notes with $105,000,000 aggregate principal, a 10% annual interest rate and nine-year maturity, subject to a $3,150,000 original issue discount, payable primarily from GSK milestone and royalty payments. A related agreement sold 65% of GSK milestone and royalty proceeds arising after repayment of the notes for $1,575,000, with Spero retaining 35%. The company estimates that net proceeds from this royalty financing, together with existing cash and cash equivalents, will fund operations into the second half of 2029.
SP001 (IBI355) has completed two Phase 1 studies in healthy volunteers and a Phase 1b multiple-ascending-dose trial in Sjögren’s disease, showing a generally benign safety profile and signals of disease-activity improvement. Spero currently expects to initiate a Phase 2 trial in IgG4-related disease in the second quarter of 2027, while Innovent plans a Phase 2 trial in Sjögren’s disease in China by early 2027, with potential expansion of SP001 into additional autoimmune and inflammatory indications.
Spero Therapeutics director Milind Deshpande received new equity awards as part of his compensation. He was granted 10,000 restricted stock units, each representing one share of common stock upon vesting, and a stock option for 20,000 shares at an exercise price of $2.15 per share.
The RSUs vest on June 23, 2027, contingent on his continued service. The option also vests and becomes fully exercisable on June 23, 2027 under the same service condition. Following the grant, he directly holds 101,454 shares of common stock.
Spero Therapeutics director Kathleen Tregoning received new equity awards. She was granted 10,000 restricted stock units, each convertible into one share of common stock upon vesting on June 23, 2027, subject to her continued service.
She also received stock options for 20,000 shares of common stock at an exercise price of $2.1500 per share, vesting in full on June 23, 2027 and expiring on June 23, 2036. Following these awards, she directly holds 85,000 shares of common stock.
Director Cynthia Smith of Spero Therapeutics, Inc. received new equity compensation in the form of restricted stock units and stock options. She was granted 10,000 shares of Common Stock at a price of $0.00 per share, increasing her direct holdings to 85,000 shares. She also received a stock option for 20,000 shares of Common Stock with an exercise price of $2.15 per share, expiring on June 23, 2036.
The 10,000 RSUs will vest on June 23, 2027, provided she continues serving through that date. The 20,000-share option will also vest and become fully exercisable on June 23, 2027 under the same service condition. These awards are compensation-related grants rather than open-market purchases or sales.
Spero Therapeutics director Patrick V.J.J. Vink received new equity awards. He was granted 10,000 restricted stock units, each representing one future common share upon vesting on June 23, 2027, subject to continued service. He was also awarded options on 20,000 shares at an exercise price of $2.15 per share, vesting in full on June 23, 2027 and expiring on June 23, 2036. Following these grants, he directly owns 85,000 common shares.
Spero Therapeutics director Frank E. Thomas received new equity awards as part of his compensation. He was granted 10,000 shares of common stock in the form of restricted stock units, which vest on June 23, 2027, as long as he continues serving through that date.
He was also granted options to buy 20,000 shares of common stock at an exercise price of $2.15 per share. These options vest and become exercisable in full on June 23, 2027, subject to his continued service as a director. After the stock grant, he holds 85,000 common shares directly.
Spero Therapeutics director Scott Thomas Jackson reported new equity awards. He received 10,000 shares of common stock in the form of restricted stock units (RSUs), each representing one share upon vesting. These RSUs vest on June 23, 2027, conditioned on his continued service.
He was also granted stock options for 20,000 shares of common stock at an exercise price of $2.15 per share, expiring on June 23, 2036. These options vest and become exercisable in full on June 23, 2027, subject to continued board service. Following the RSU award, his direct common stock holdings total 85,000 shares. These are compensation-related grants, not open-market purchases or sales.
Spero Therapeutics director John C. Pottage Jr. reported equity awards consisting of both restricted stock units and stock options. He received 10,000 shares of Common Stock as restricted stock units that each convert into one share when they vest on June 23, 2027, subject to his continued service. Following this award, he directly holds 85,000 shares of common stock. He was also granted a stock option for 20,000 shares of common stock with an exercise price of $2.15 per share, expiring on June 23, 2036, which will vest and become exercisable in full on June 23, 2027 if he continues to serve as a director.
Spero Therapeutics, Inc. held its 2026 annual meeting of stockholders, where stockholders approved a new 2026 Stock Incentive Plan covering up to 12,895,866 shares of common stock. This plan will be used for future equity awards to employees, directors, and other service providers.
Stockholders also approved an amendment to the Amended and Restated Certificate of Incorporation to increase authorized common stock from 120,000,000 shares to 240,000,000 shares, expanding the capacity for future issuances. A quorum of 41,061,190 shares, or about 70.91% of the 57,901,493 shares outstanding as of April 24, 2026, was present, and director nominees and other proposals received the required support.
Spero Therapeutics announced that the FDA has approved Utebzi (tebipenem pivoxil), an oral antibiotic for adults with complicated urinary tract infections (cUTIs), including pyelonephritis, who have limited or no alternative oral options. This is the first and only oral carbapenem antibiotic approved for these patients in the US.
The approval stems from a global development and exclusive licensing agreement with GSK and was granted ahead of the Prescription Drug User Fee Act date of June 18, 2026. Phase III PIVOT-PO data showed oral tebipenem pivoxil was non-inferior to intravenous imipenem-cilastatin, with a generally similar safety profile.