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Exhibit 12.1

United Therapeutics Corporation
Ratio of Earnings to Fixed Charges
(Unaudited)

	Years Ended December 31,
	2007		2006		2005		2004		2003
	(in thousands, except ratio)
Earnings (losses) from continuing operations before fixed charges	$	19,859	$	28,982	$	42,893	$	13,209	$	(11,526	)
Fixed charges
Interest expenses, net of capitalized interest	$	2,175	$	482	$	29	$	3	$	112
Capitalized interest		689		—		—		—		—
Portion of rentals representative of interest factor		1,885		1,172		—		—		—
Total fixed charges		4,749		1,654		29		3		112
Ratio of earnings to fixed charges		4.18		17.52		1,479.07		4,403.00		—
Excess fixed charges over earnings	$	—	$	—	$	—		—	$	11,638

NOTE: The Ratio of Earnings to Fixed Charges should be read in conjunction with the Consolidated Financial Statements and related Notes and Management's Discussion and Analysis of Financial Condition and Results of Operations in United Therapeutics Corporation's Annual Report on Form 10-K for the year ended December 31, 2007.

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Exhibit 12.1

United Therapeutics Corporation Ratio of Earnings to Fixed Charges (Unaudited)