Spero Therapeutics, Inc.
Spero Therapeutics, Inc. (Nasdaq: SPRO) is a clinical-stage biopharmaceutical company focused on identifying and developing novel treatments for rare diseases and conditions with high unmet medical needs. Founded in 2013, the company has built its business around acquiring and developing product and technology rights… From the company’s description.
Margins and return on equity change in ; everything else in percent. Fewer shares and less debt are shown plainly, not as bad news — it depends what you make of buybacks. Dotted labels explain each measure. is shown separately from the annual figures.
What Spero Therapeutics, Inc. does
In the company’s own words
Spero Therapeutics, Inc. (Nasdaq: SPRO) is a clinical-stage biopharmaceutical company focused on identifying and developing novel treatments for rare diseases and conditions with high unmet medical needs. Founded in 2013, the company has built its business around acquiring and developing product and technology rights while constructing an intellectual property portfolio centered on innovative antibiotic therapies.
The company's primary clinical-stage product candidate is tebipenem HBr, a potential first oral carbapenem designed to treat complicated urinary tract infections, including pyelonephritis, in adult patients. Tebipenem HBr has completed a pivotal Phase 3 trial called PIVOT-PO, which met its primary endpoint and was stopped early for efficacy. In September 2022, Spero entered into an exclusive license agreement with GlaxoSmithKline for the development, manufacturing, and commercialization of tebipenem HBr outside of certain Asian territories. Under this partnership, Spero received a $66 million upfront payment and is eligible to receive up to $525 million in development, sales, and commercial milestone payments, plus tiered royalties on net product sales. GSK submitted a New Drug Application for tebipenem HBr in December 2025, with an FDA decision date set for June 18, 2026.
Spero has received significant regulatory designations for tebipenem HBr, including Qualified Infectious Disease Product status and fast track designation from the FDA. The company's website is www.sperotherapeutics.com.
Historically, Spero pursued development of SPR206, an intravenous investigational therapy for hospital-acquired and ventilator-associated bacterial pneumonia caused by carbapenem-resistant pathogens, and SPR720, an oral antibiotic candidate for nontuberculous mycobacterial pulmonary disease. In March 2025 and November 2025, respectively, the company ceased development of these programs to focus resources on advancing tebipenem HBr and exploring opportunities to expand its clinical-stage product portfolio. The company has not generated revenue from product sales and has a history of operating losses.
Company details
- Sector
- Healthcare
- Industry
- Pharmaceutical Preparations
- Headquarters
- CAMBRIDGE, MA
- Fiscal year end
- December
- CIK
- 1701108
- SIC
- 2834
Financial performance, year by year
Fiscal 2017–2025 · USDThe full income statement, balance sheet and cash flow for each of these years — every figure traceable to its filing — is on the Financials tab with a free account.
Who owns Spero Therapeutics, Inc. — and what changed
Funds as of 2026Q2 · superinvestors as of 2026-06-30
Largest fund holders · Spero Therapeutics, Inc.’s weight in each
Fund ownership is a floor, not a census — pensions, insurers and people holding shares directly are not visible here.
Fund ownership counts N-PORT filers only, so it is a floor rather than a census — pensions, insurers and direct holders are not visible here, and the remainder is not “held by individuals”.
Every fund and institutional holder, quarter by quarter, is on the Ownership tab with a free account.
Recent filings
All filings →Each filing opens into its own statements and disclosures here.
Put this business in context.
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