Johannes Jacob Pieter Kastelein sold $1.3M of NAMS stock

Johannes Jacob Pieter Kastelein, Chief Scientific Officer of NewAmsterdam Pharma Co N.V. (NAMS), sold 50,246 shares of NAMS stock worth $1.3M, per an SEC Form 4 filed Oct 2, 2026.

The sale was pre-arranged (a 10b5-1 plan or an option exercise), not a fresh decision.

The trade happened on Sep 30, 2026, 2 days before it was made public.

NAMS has moved -17.9% since the trade date, from $24.32 to $19.97 (Nov 12, 2026 close).