Property and Equipment

12 Months Ended

Dec. 31, 2013

Property and Equipment

Property and Equipment

8. Property and Equipment

        Property and equipment, net consisted of the following (in thousands):

	December 31,
	2013			2012
Manufacturing equipment	$	2,812		$	—
Laboratory equipment		14,039			16,315
Computer and office equipment		5,202			6,476
Furniture and fixtures		2,365			2,449
Software		12,352			11,047
Construction in process		996			1,460
Leased vehicles		4,472			—
Leasehold improvements		36,827			36,770
		79,065			74,517
Less accumulated depreciation and amortization		(41,689	)		(36,980	)
	$	37,376		$	37,537

        The Company has entered into capital leases for certain computer, vehicles and office equipment (Note 11). As of December 31, 2013 and 2012, the Company had approximately $5.5 million and approximately $1.4 million, respectively, of assets under capital leases with accumulated amortization balances of approximately $1.2 million and approximately $0.9 million, respectively.

        Depreciation and amortization expense of property and equipment, including equipment recorded under capital leases, was approximately $11.7 million, approximately $11.3 million, and approximately $10.0 million for the years ended December 31, 2013, 2012 and 2011, respectively.

        In October 2012, the Company entered into an amendment to its Cambridge, Massachusetts building lease, pursuant to which the term of the lease was extended by 24 months. As a result of this amendment, the Company extended on a prospective basis the period over which it amortizes its leasehold improvements.