EXHIBIT 12.1
Omeros Corporation
Computation of Deficiency in the Coverage of Fixed Charges by Earnings Before Fixed Charges
	For the nine months ended						Year Ended December 31,
	2017			2016			2015			2014			2013			2012
	(in thousands)			(in thousands)
Earnings before fixed charges:
Loss from continuing operations before income taxes	$	(36,930	)	$	(66,745	)	$	(75,096	)	$	(73,673	)	$	(39,796	)	$	(38,444	)
Add fixed charges	10,813			16,697			8,295			6,824			5,621			2,305
Add amortization of capitalized interest	—			—			—			—			—			—
Add distributed income of equity investees	—			—			—			—			—			—
Subtract capitalized interest	—			—			—			—			—			—
Loss before fixed charges	$	(26,117	)	$	(50,048	)	$	(66,801	)	$	(66,849	)	$	(34,175	)	$	(36,139	)
Fixed Charges:
Interest expense	$	7,578		$	6,359		$	2,709		$	2,710		$	1,865		$	1,355
Amortization of debt expense and loss from extinguishment of debt	588			7,055			2,177			759			502			374
Estimate of interest expense within rental expense	2,647			3,283			3,409			3,355			3,254			576
Preference security dividend requirements of consolidated subsidiaries	—			—			—			—			—			—
Total fixed charges	$	10,813		$	16,697		$	8,295		$	6,824		$	5,621		$	2,305
Deficiency of earnings available to cover fixed charges	$	(36,930	)	$	(66,745	)	$	(75,096	)	$	(73,673	)	$	(39,796	)	$	(38,444	)