Silence, AbCellera emerge as best-in-class contenders as Sionna sinks

Updates from the clinic this week include Phase II wins for new therapeutic classes in development for polycythemia vera and vasomotor symptoms of menopause. The week’s biggest setback came from Sionna, which lost nearly all of its value after a Phase II miss in cystic fibrosis.

Phase II results announced Monday by Silence Therapeutics plc (NASDAQ:SLN) put divesiran, the most advanced siRNA therapy for polycythemia vera, in best-in-class contention — the latest example of an siRNA candidate potentially outperforming drugs based on other modalities...