144/A 0001968582-26-000868 0002000389 XXXXXXXX LIVE 0001936258 NewAmsterdam Pharma Company N.V. 001-41562 Gooimeer 2-35 DC Naarden P7 1411 31-0-35-206-2971 Kastelein Johannes Jacob Pieter Affiliate Ordinary Shares J.P. Morgan Securities LLC 270 Park Avenue - 10th Floor New York NY 10017 250000 6967500 119537169 08/25/2026 Nasdaq Ordinary Shares 08/24/2026 Option Exercise Issuer N 250000 08/24/2026 Cash Y The shares represented on this filing are for shares expected to be sold in the next 90 days by Futurum B.V., John Kastelein as Director 08/24/2026 03/31/2026 /s/ J.P. Morgan Securities LLC as agent and attorney-in-fact for Kastelein Johannes Jacob Pieter