Balance Sheet Components

6 Months Ended

Jun. 30, 2021

Balance Sheet Related Disclosures [Abstract]

Balance Sheet Components

4. Balance Sheet Components

Property and Equipment, net

Property and equipment, net, consists of the following:

	June 30,			December 31,
	2021			2020
	(in thousands)
Computer hardware and software	$	1,260		$	2,758
Furniture and equipment		896			1,865
Leasehold improvements		5,799			9,220
		7,955			13,843
Less: Accumulated depreciation		(4,675	)		(7,088	)
	$	3,280		$	6,755

Depreciation expense for the three months ended June 30, 2021 and 2020 was $0.9 million and $0.7 million, respectively. Depreciation expense for the six months ended June 30, 2021 and 2020 was $3.5 million and $1.3 million, respectively.

During the six months ended June 30, 2021, the Company removed property and equipment that was fully-depreciated from the condensed consolidated balance sheet, resulting in a decrease of $1.8 million to the gross balance of property and equipment and accumulated depreciation.

During the six months ended June 30, 2021, the Company wrote off property and equipment related to a multi-tenant building under an operating lease for office space in Cambridge, Massachusetts, in connection with the early termination of the lease by the Company. The gross balance of property and equipment and accumulated depreciation decreased by $3.3 million. Of the decrease to the gross balance, $2.1 million was depreciated immediately upon termination of the lease, and $1.2 million had been depreciated prior to the termination of the lease. Additionally, during the three months ended June 30, 2021, the Company wrote off property and equipment related to a different multi-tenant building under an operating lease for office space in Cambridge, Massachusetts, in connection with a sublease of a portion of the leased office space. The gross balance of property and equipment and accumulated depreciation decreased by $0.9 million. Of the decrease to the gross balance, $0.5 million was depreciated immediately upon termination of the lease, and $0.4 million had been depreciated prior to the termination of the lease.

The useful life for computer hardware and software is three years, furniture and equipment is five years and leasehold improvements is the lesser of the useful life or the term of the respective lease.

Accrued Expenses

Accrued expenses consist of the following:

	June 30,		December 31,
	2021		2020
	(in thousands)
Accrued research and development costs	$	43,169	$	34,398
Employee-related		8,283		14,769
Professional services		9,438		5,184
Other		733		500
	$	61,623	$	54,851