Exhibit 99.1 Alpine Immune Sciences Reports First Quarter 2024 Financial Results SEATTLE, Washington - May 9, 2024 - Alpine Immune Sciences, Inc. (NASDAQ: ALPN), a leading clinical-stage immunotherapy company focused on developing innovative treatments for autoimmune and inflammatory diseases, today reported financial results for the first quarter ended March 31, 2024. On April 10, 2024, Vertex Pharmaceuticals Incorporated (Nasdaq: VRTX) and Alpine announced that the companies had entered into a definitive ...