Amphastar Pharmaceuticals' stock experienced a 24-hour plunge of 8.24% in post-market trading.

The sharp decline followed the company's release of disappointing first-quarter financial results. Amphastar reported adjusted earnings per share of $0.42, significantly missing the analyst consensus estimate of $0.70. Revenue of $171.17 million also fell short of expectations, while GAAP net income plummeted 75% year-over-year to $6.4 million.

The earnings miss was driven by lower average selling prices for key products including BAQSIMI, glucagon, phytonadione, and epinephrine, which reduced gross margin. Additionally, higher manufacturing expenses from facility expansion and increased research & development costs, including a $2 million licensing payment, further pressured profitability.