Spero Therapeutics, Inc. (SPRO) AI Stock Analysis

Spero Therapeutics, Inc. is a clinical-stage biopharmaceutical company dedicated to discovering, developing, and commercializing treatments targeting multi-drug resistant bacterial infections and rare diseases in the United States. Its pipeline includes tebipenem pivoxil hydrobromide (HBr), an oral carbapenem antibiotic for complicated urinary tract infections such as pyelonephritis in adults. It is also developing SPR206, an intravenous agent for hospital-treated Gram-negative infections, and SPR720, an oral therapy for non-tuberculous mycobacterial pulmonary disease. The company collaborates with Meiji Seika Pharma Co., Ltd. for tebipenem HBr, Everest Medicines for SPR206 across parts of Asia, and both the Bill & Melinda Gates Medical Research Institute and Vertex Pharmaceuticals Incorporated for SPR720 and SPR719.

Spero Therapeutics achieved a 5-year revenue compound annual growth rate of 44.9% from FY2020 to FY2025. Annual revenue has experienced wide swings, rising from $3.1M in FY2021 to $103.8M in FY2023, before falling to $48.0M in FY2024 and rebounding to $59.6M in FY2025. Net income was positive in FY2023 at $22.8M and in FY2025 at $8.6M, which came with a 14.4% net margin. Over the trailing twelve months, revenue was $47.0M with diluted EPS of $0.14 and an operating margin of 14.1%. In the latest quarter ended June 30, 2026, revenue dropped 95.6% year-over-year, while quarterly earnings grew 75.3%.

As of June 30, 2026, Spero Therapeutics held $50.8M in cash and short-term investments against $2.0M in total debt, resulting in net cash of $48.7M. Total assets stood at $52.8M alongside shareholders' equity of $44.2M. The company maintains strong liquidity with a current ratio of 6.12 and a debt-to-equity ratio of 0.05. Operating cash flow and free cash flow were both -$12.6M in FY2025, and operating cash flow has remained negative in each fiscal year since FY2021. Over the trailing 5-year period, the company's share count increased by 80.4%.

At a last close of $1.10 on October 16, 2026, Spero Therapeutics had a market capitalization of $64.1M and an enterprise value of $24.9M. The stock traded at a trailing P/E ratio of 7.9x, an EV-to-EBITDA of 3.8x, and a price-to-sales multiple of 1.4x. These figures compare with median metrics of 24.6x trailing P/E, 12.0x EV-to-EBITDA, and 4.1x price-to-sales across its peer group of 1056 US-listed Healthcare peers. Over the trailing year, SPRO fell 53.2%, trailing the S&P 500 (SPY) gain of 16.8%, and its 5-year return of -93.5% lagged SPY's 83.0% return.

Wall Street coverage consists of 1 Strong Buy and 1 Hold rating. The mean price target is $5.00, representing a 354.5% premium over the last close of $1.10. For the fiscal year ending December 31, 2026, analysts estimate an EPS of -$0.58 and revenue of $258,000. For the next fiscal year, two analysts project EPS of -$0.10 and revenue of $0, reflecting a 100.0% decline. Spero Therapeutics beat EPS estimates in each of its last 4 quarters, with its next earnings announcement scheduled for November 12, 2026.

This page is an AI-written research summary of Spero Therapeutics, Inc. (SPRO). The text was generated on October 30, 2026 from Quotelinks data as of October 16, 2026 (company profile, annual results, latest balance sheet, valuation, price performance and analyst estimates). An automatic check rejects any draft that contains a figure not found in that data. It is not investment advice; verify figures on the linked tabs before making decisions.

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