Dynavax Technologies

Dynavax Technologies is an Emeryville, California biopharmaceutical company built around CpG 1018, a proprietary vaccine adjuvant that sharpens the immune system's response. Its flagship product, HEPLISAV-B, is the first and only two-dose adult hepatitis B vaccine approved in the U.S. and Europe, and had grown to roughly 44% U.S. market share by the end of 2024. Beyond hepatitis B, Dynavax licenses CpG 1018 to other vaccine developers - most visibly as an ingredient in several COVID-19 vaccines - and has advanced its own pipeline in shingles, plague, pandemic influenza, and Lyme disease. In December 2025 Sanofi agreed to acquire Dynavax for about $2.2 billion; the deal closed in February 2026.