Exhibit 99.1 Ionis reports first quarter 2024 financial results WAINUATM launch on track; EU and Canada approval decisions expected this year Olezarsen NDA submitted to FDA for FCS; preparing EU regulatory submission Positive Phase 3 donidalorsen data for HAE; preparing regulatory submissions On track to achieve 2024 financial guidance CARLSBAD, Calif., May 7, 2024 – Ionis Pharmaceuticals, Inc. (Nasdaq: IONS) (the “Company”), today reported financial results for the first quarter ended March 31, 2024. “Ioni ...