Is Spero Therapeutics, Inc. overvalued or undervalued?

As of 27 March 2025, Spero Therapeutics, Inc. has moved from a fair to a risky valuation grade. The company is currently considered overvalued given its high Price to Book Value of 4.13 and negative EV to EBIT and EV to EBITDA ratios of -1.04, indicating significant financial challenges. Additionally, the company's Return on Equity (ROE) is alarmingly low at -203.20%, further underscoring its precarious financial position.
In comparison to peers, Spero Therapeutics has a worse EV to EBITDA ratio than Shattuck Labs, Inc. at -0.6631 and Enzo Biochem, Inc. at -0.1144, both of which also face risky valuations. Despite the company's strong year-to-date stock return of 94.17% compared to the S&P 500's 12.22%, the long-term outlook remains concerning, particularly with a five-year return of -80.22% against the S&P 500's 96.61%.