Is Amphastar Pharmaceuticals, Inc. overvalued or undervalued?

As of 7 July 2025, the valuation grade for Amphastar Pharmaceuticals, Inc. moved from expensive to attractive, indicating a shift towards a more favorable assessment. The company appears undervalued based on its current metrics, with a P/E ratio of 10, a Price to Book Value of 1.91, and an EV to EBITDA of 7.14. In comparison, peers like Prestige Consumer Healthcare, Inc. have a P/E of 15.85 and an EV to EBITDA of 11.55, while Corcept Therapeutics, Inc. is considered very expensive with a P/E of 60.03.
Despite the attractive valuation, Amphastar has struggled in recent performance, with a year-to-date return of -26.10% compared to the S&P 500's positive return of 12.22%. This underperformance over the past year, alongside a 1-year return of -44.88%, suggests that while the stock may be undervalued, market sentiment has not yet aligned with its valuation metrics.