Annexon shares surge 13.91% premarket as Jefferies reiterates strong buy rating and highlights M&A-driven complement inhibitor demand.

Annexon surged 13.91% in premarket trading amid renewed analyst optimism and industry tailwinds. Jefferies reiterated a Buy rating with a $10 price target, citing Biogen’s $5.6 billion acquisition of Apellis Pharmaceuticals as a sign of strong pharmaceutical interest in the complement inhibitor space. The firm also highlighted Annexon’s upcoming Phase III data for ANX007 in Q4 2026 and a favorable analyst consensus, with price targets ranging from $8 to $27. Additionally, Annexon submitted its first Marketing Authorization Application in the EU for ANX005 and received a $14 Buy rating from H.C. Wainwright, emphasizing the differentiation of its pipeline. These developments collectively fueled premarket enthusiasm and a sharp upward move in the stock.