Spero Therapeutics, Inc (SPRO) Fair Value & Analysis
Healthcare · US · Market cap $129M
Spero Therapeutics, Inc
SPRO · US
Fair value as of: Jul 21, 2026
From 11 valuation models · updated 20 days ago
Fair value updated Jul 21, 2026, revised from $3.26 to $2.52 (−22.7%) since Jun 24, 2026. Share price −41.9% over the past month.
A solid business, screening 100% undervalued on our models.
What matters now
- The price is below even our cautious bear case ($1.89). The market is more pessimistic than our downside scenario.
- Solid quality (69/100) at a price below fair value, the discount is the argument here, not the business quality.
Price vs Fair Value (5 years)
White line = price, green steps = our fair value per fiscal year, dashed = 300-day average. As of Jul 21, 2026.
How to read this chart
60‑month range $0.5600 – $19.51 · fair‑value band $1.89 – $3.15 · the $1.26 price screens below the $2.52 fair value. Dashed = 300-day average. As of Jul 21, 2026.
Analysis
Spero Therapeutics, Inc (SPRO) currently trades at $1.26, while our model-based Fair Value estimate is $2.52, implying the stock looks roughly 100.0% undervalued today. The Quality Score stands at 69/100 (solid quality), in the Healthcare sector. Bull case: trading below our estimate, it may offer upside if the fundamentals hold. Bear case: a low price can be a value trap when quality is weak or the data is thin (evidence: medium), always confirm before acting.
Over the trailing twelve months, Spero Therapeutics, Inc generated revenue of $61.2M at a net margin of 24.9%. It earns a return on equity of 35.1%. The balance sheet holds a net cash position of $37.4M. The stock trades on a trailing P/E of 8.2. Fundamentals as of Jul 21, 2026
Our scenario range runs from $1.89 (bear case) to $3.15 (bull case); at $1.26, the current price sits below that range. Bear and bull are the same models run on conservative and optimistic assumptions (margins, growth, valuation multiples), so a plausible valuation range, not a price target. The share trades about 61% below its 52-week high, currently below its 200-day average. For context, the median of 10 Healthcare peers we cover trades at -43% fair-value upside, at 100%, SPRO screens cheaper than that median.
Fair Value models
Each model estimates fair value its own way; the Fair Value above is the evidence-weighted blend. Evidence (0–100) measures how completely this model’s inputs are available: well-fed models carry more weight in the blend. The spread across models is intentional, each one stresses a different value driver; dividend models, for instance, come out structurally low when payout is small.
All 11 models by family
Widest divergence: Dividend Discount ($10.41) versus Asset-Based ($0.6800). Highest evidence: Residual Income (76).
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Key figures & financial health
More key figures
Figures from reported company fundamentals · as of Jul 21, 2026. TTM = trailing twelve months.
Quality Score breakdown
Of which business quality 61 · Market factors (momentum, volatility) 8
Non-valuation factor families (profitability, growth, cashflow, financial strength, momentum …), each academically grounded. Valuation itself sits in the Fair Value and is deliberately excluded here to avoid double-counting.
About the company
Spero Therapeutics, Inc., a clinical-stage biopharmaceutical company, focuses on identifying and developing novel treatments for multi-drug resistant (MDR) bacterial infections and rare diseases in the United States.
Full company description
Spero Therapeutics, Inc., a clinical-stage biopharmaceutical company, focuses on identifying and developing novel treatments for multi-drug resistant (MDR) bacterial infections and rare diseases in the United States. The company's product candidates include Tebipenem HBr (tebipenem pivoxil hydrobromide), an oral carbapenem-class antibiotic to treat complicated urinary tract infections, including pyelonephritis for adult patients, which has completed second Phase 3 trial. It has license agreement with Meiji Seika Pharma Co., Ltd. to develop, manufacture, and commercialize tebipenem pivoxil and tebipenem HBr; and Everest Medicines to develop, manufacture, and commercialize SPR206 in Greater China, South Korea, and Southeast Asian countries. Spero Therapeutics, Inc. was incorporated in 2013 and is headquartered in Cambridge, Massachusetts.
Company description, as reported by the company or data provider.
Revenue & earnings trend
FY2021 – FY2025 · reported fiscal years
Spero Therapeutics, Inc reported revenue of $59.6M in FY2025 versus $3.1M in FY2021, a compound +109.9%/yr. Reported net income was $8.6M in FY2025.
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Peer Group
Biotechnology · 601 stocks
How this stock ranks against its industry: the green marker is this stock, the band is the typical 25–75% peer range, and the tick is the median.
Valuation Multiples vs Biotechnology median · lower = cheaper
Snowflake
Five quick dimensions, each 0 to 100: VALUE (fair-value potential), FUTURE (revenue growth), PAST (return on equity), HEALTH (low debt), DIVIDEND (yield). Green = this stock, grey = typical sector peer.
Values & ESG
Does this company touch areas you may want to avoid? The classification is inferred from sector and industry.
ESG scores are not available for this stock yet. Values and ESG data are contextual and can differ between providers.
Similar stocks
10 more Biotechnology stocks, each showing price versus our Fair Value estimate (as of Jul 21, 2026).
| Stock | Price | Fair Value | vs Fair Value |
|---|---|---|---|
| Vertex Pharmaceuticals Incorporated VRTX | $486.03 | $278.78 | -43% |
| Regeneron Pharmaceuticals, Inc REGN | $664.45 | $594.40 | -11% |
| Samsung Biologics Co 207940 | 1,368,000 KRW | 1,091,384 KRW | -20% |
| Celltrion, Inc 068270 | 175,800 KRW | 76,325 KRW | -57% |
| WuXi Biologics (Cayman) Inc 2269 | HK$39.54 | HK$30.42 | -23% |
| Innovent Biologics, Inc 1801 | HK$86.70 | HK$19.66 | -77% |
| Sino Biopharmaceutical Limited 1177 | HK$5.26 | HK$3.36 | -36% |
| ALTEOGEN Inc 196170 | 276,500 KRW | 44,444 KRW | -84% |
| RemeGen Co 688331 | ¥134.02 | ¥26.99 | -80% |
| Biocon Limited BIOCON | ₹440.70 | ₹57.36 | -87% |
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Frequently asked questions
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How we calculate Fair Value
Each company is valued through a stack of independent intrinsic-value models (DCF variants, residual-income, multiples and more), blended into one family-balanced consensus and weighted by how much trustworthy data backs it. A separate quality layer scores the fundamentals. Every input is real reported data, nothing guessed.
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