Spero Therapeutics Inc. Common Stock (SPRO)

FairStock Score: 71/100 — STEADY

Key Financials

Strengths

• Solid return on equity of 16.3% above cost of capital
• Conservative balance sheet with debt-to-equity of just 0.05, providing financial flexibility
• Altman Z-Score of 4.0 confirms minimal bankruptcy risk and strong solvency
• Revenue growth of 323.9% demonstrates strong top-line momentum
• FairStock composite score of 71/100 places it in the top tier across value, quality, and momentum factors

Concerns

• Trades significantly above Graham Number ($2) with negative 53% margin of safety—limited downside protection
• Currently unprofitable—sustained losses could lead to dilutive capital raises or balance sheet deterioration

AI Analysis

Spero Therapeutics Inc. Common Stock is a micro-cap healthcare company valued at $166 million. Revenue stands at $67 million, though the company is currently unprofitable. From a quality standpoint, Spero shows healthy Altman Z-Score of 4.0 and adequate 16% ROE. On valuation, the stock is reasonably priced at 18.7x earnings, with trades above its Graham Number with a negative 53% margin. Growth dynamics show revenue growing at 323.9% and profit growth of 250.9%. Our composite FairStock Score of 71/100 reflects above-average fundamentals overall. Without profitability, this remains speculative—suitable only for those with high risk tolerance and a long time horizon.

Bull Case

Spero's 324% revenue growth trajectory could accelerate as it captures additional market share in the healthcare sector. Operational leverage in the business model means incremental revenue growth could disproportionately boost bottom-line profitability.

Bear Case

Without a clear path to profitability, continued cash burn forces either dilutive equity raises or debt accumulation that destroys shareholder value. Regulatory changes, input cost inflation, or demand normalization represent underappreciated risks that could materially impact forward estimates.

Data from SEC filings. AI analysis is for educational purposes only — not investment advice. Scoring methodology · Disclaimer