EX-21 4 a2182934zex-21.htm EXHIBIT 21
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Exhibit 21

SUBSIDIARIES OF THE REGISTRANT

Lung Rx, Inc., a Delaware Corporation

Unither Telmed, Ltd, a Delaware Corporation

Unither Pharmaceuticals, Inc., a Delaware Corporation

United Therapeutics Europe, Ltd., a United Kingdom Company

Unither Pharma, Inc., a Delaware Corporation

Medicomp, Inc., a Delaware Corporation

Unither Neurosciences, Inc., a Delaware Corporation

Unither.com, Inc., a Delaware Corporation

LungRx Limited, a United Kingdom Company

Unither Biotech Inc., a Canadian Company

Unither Virology, LLC, a Delaware Corporation