SCHEDULE 13G/A

ADAPTIMMUNE THERAPEUTICS PLC

Ordinary Shares · CUSIP: 00653A107

Event date: 2025-08-15

Reporting persons may disclose overlapping interests. Their amounts are shown individually and are not added into a filing total.

Filing-level shares

Unavailable

Percent of class

Unavailable

• EcoR1 Capital, LLC

  Shares: 66,000,000.00 · Class: 4.2%

• Oleg Nodelman

  Shares: 66,000,000.00 · Class: 4.2%

• EcoR1 Capital Fund Qualified, L.P.

  Shares: 63,184,650.00 · Class: 4.0%

Amounts are as disclosed in this filing. Schedule type alone does not establish investment intent.