SCHEDULE 13G/A

INSMED INC

Common Stock, par value $0.01 per share · CUSIP: 457669307

Event date: 2025-09-30

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

• Darwin Global Management, Ltd.

  Shares: 20,457,445.00 · Class: 9.7%

• Dr. Abhishek Trehan

  Shares: 20,457,445.00 · Class: 9.7%

• Darwin Global Master Fund, Ltd.

  Shares: 20,085,806.00 · Class: 9.5%

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