LFUS vs IONS Comparison

Littelfuse is a supplier of circuit protection products (such as fuses and relays) for the transportation, industrial, telecommunications, and consumer electronics end markets. Littelfuse also holds a minority power semiconductor business, primarily serving high-voltage industrial applications. Littelfuse sells globally across both distribution and direct channels, and organizes its business into the three segments of electronics, transportation, and industrial. Littelfuse is a serial acquirer of smaller, bolt-on adjacent firms.

Ionis Pharmaceuticals is the leading developer of antisense technology to discover and develop novel drugs. Its broad clinical and preclinical pipeline targets a wide variety of diseases, with an emphasis on cardiovascular, metabolic, neurological, and rare diseases. Ionis and Biogen brought Spinraza to market in 2016 as a treatment for spinal muscular atrophy, and Biogen launched ALS drug Qalsody in 2023. Ionis brought two additional drugs to market via its cardiovascular-focused subsidiary Akcea, including ATTR amyloidosis drug Tegsedi (2018) and cardiology drug Waylivra (Europe, 2019). Ionis and AstraZeneca launched polyneuropathy drug Wainua in 2024. Ionis marked its first two independent launches in 2025 for Tryngolza (for FCS) and Dawnzera (for HAE).