EX-21.1 16 exhibit21-1.htm EXHIBIT 21.1
Exhibit 21.1
LIST OF SUBSIDIARIES FOR THE REGISTRANT
Akcea Therapeutics, Inc., a Delaware Corporation
Akcea Therapeutics Canada Inc., a Canadian Corporation
Akcea Therapeutics France SAS, a French Company*
Akcea Therapeutics Germany GmbH, a German Corporation
Akcea Therapeutics UK Limited, a United Kingdom Limited Private Company
Akcea Securities Corporation, a Massachusetts Corporation*
Akcea Therapeutics Ireland Limited, an Irish Private Company
Isis USA Limited, a United Kingdom Limited Private Company
Osprey Therapeutics, Inc., a Delaware Corporation
PerIsis I Development Corporation, a Delaware Corporation**
Symphony GenIsis, Inc., a Delaware Corporation**
Ionis Development (Ireland) Limited, an Irish Private Company

* | Akcea Therapeutics France SAS and Akcea Securities Corporation were dissolved in December 2022.

** | PerIsis I Development Corporation and Symphony GenIsis, Inc. were dissolved in September 2021.