SAN DIEGO, June 08, 2026 (GLOBE NEWSWIRE) -- Johnson Fistel, PLLP is investigating whether Amphastar Pharmaceuticals, Inc. (NASDAQ: AMPH) or certain of its executive officers violated federal securities laws. The investigation focuses on investors’ losses and whether they may be recovered under federal securities laws.

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Background of the Investigation
On May 7, 2026, Amphastar reported its financial results for the first quarter of 2026. The Company disclosed that BAQSIMI revenues decreased 15% year-over-year to $32.4 million, compared to $38.4 million in the prior-year period, despite an 8% increase in units sold.

Amphastar attributed the BAQSIMI revenue decline to lower average selling prices, stating that the lower average selling price was driven by higher rebates and higher 340B pharmacy discounts, some of which may have been duplicated. The Company also stated that it now expected BAQSIMI revenue growth to be flat to up low single digits for 2026 due to the previously mentioned pricing pressures.

Following these disclosures, Amphastar’s stock price fell more than 20% on May 8, 2026, causing significant losses to investors.

On May 13, 2026, Amphastar provided additional detail regarding BAQSIMI at the Bank of America Global Healthcare Conference. Management stated that “the biggest surprise was the impact of the double discounting” from 340B programs on BAQSIMI.

In light of these disclosures, Johnson Fistel is investigating whether Amphastar complied with federal securities laws. If you suffered losses, contact Johnson Fistel for more information.

About Johnson Fistel, PLLP | Securities Fraud & Investor Rights
Johnson Fistel, PLLP is a nationally recognized shareholder rights law firm with offices in California, New York, Georgia, Idaho, and Colorado. The firm represents individual and institutional investors in shareholder class actions and derivative lawsuits. Johnson Fistel has been recognized as one of the Top 10 Plaintiff Law Firms by ISS Securities Class Action Services. In 2024, the firm recovered approximately $90,725,000 for investors.

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Contact
Johnson Fistel, PLLP
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James Baker, Investor Relations – or – Frank J. Johnson, Esq.
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