Share-Based Payments

Pursuant to the terms of the Company's 2014 Stock Incentive Plan (the "2014 Plan"), the number of shares authorized for issuance automatically increases on the first day of each fiscal year. On January 1, 2017, the number of shares reserved for issuance under the 2014 Plan increased by 982,164 shares. As of June 30, 2017, the total number of shares of common stock available for issuance under the 2014 Plan was 1,989,329.

The Company also maintains the Eleven Biotherapeutics, Inc. 2009 Stock Incentive Plan, as amended and restated.

Stock-Based Compensation Expense

Stock-based compensation expense by award type was as follows (in thousands):



	Three Months Ended June 30,				Six Months Ended June 30,
	2017		2016		2017		2016
Stock options	$	268	$	444	$	455	$	879
Restricted stock	51		51		102		105
Restricted stock units	—		106		3		198
Performance stock options	—		14		—		14
Employee stock purchase plan	3		6		6		11
	$	322	$	621	$	566	$	1,207

The Company allocated stock-based compensation expense as follows in the consolidated statements of operations and comprehensive loss (in thousands):



	Three Months Ended June 30,				Six Months Ended June 30,
	2017		2016		2017		2016
Research and development expense	$	83	$	226	$	123	$	447
General and administrative expense	239		395		$	443	760
	$	322	$	621	$	566	$	1,207

At June 30, 2017, there was $1.8 million of total unrecognized compensation expense related to unvested stock options, unvested restricted stock, and shares issued pursuant to the Company's 2014 Employee Stock Purchase Plan (the "2014 ESPP"). This unrecognized compensation expense is expected to be recognized over a weighted-average period of 2.71 years.

Stock Options

A summary of the stock option activity is presented below:



	Shares		Weighted-Average Exercise Price
Outstanding at December 31, 2016	2,024,468		$	4.41
Granted	248,025		1.85
Exercised	(140,400	)	0.28
Cancelled or forfeited	(166,887	)	9.85
Outstanding at June 30, 2017	1,965,206		$	3.92
Exercisable at June 30, 2017	942,661		$	4.76
Vested and expected to vest at June 30, 2017⁽¹⁾	1,965,206		$	3.92


⁽¹⁾	Represents the number of vested options, plus the number of unvested options expected to vest. The Company adopted ASU 2016-09 as of January 1, 2017 and elected an accounting policy to record forfeitures as they occur.

Restricted Stock

From time to time, upon approval by the Board, certain employees, directors and advisors have been granted restricted shares of common stock. A summary of the restricted stock is presented below:



	Restricted Stock		Weighted-Average Grant Date Fair Value
Unvested at December 31, 2016	22,150		$	11.43
Vested	(8,860	)	11.43
Unvested at June 30, 2017	13,290		$	11.43

Restricted Stock Units

From time to time, upon approval by the Board, certain employees have been granted restricted stock units. A summary of the restricted stock units is presented below:



	Restricted Stock Units		Weighted-Average Grant Date Fair Value
Unvested at December 31, 2016	3,333		$	4.09
Vested	(3,333	)	4.09
Unvested at June 30, 2017	—		$	—

Employee Stock Purchase Plan

On March 14, 2017, the Company issued and sold 2,899 shares of its common stock pursuant to the 2014 ESPP at a purchase price of $1.71 per share. The Company has estimated the number of shares to be issued at the end of the current offering period and recognizes expense over the requisite service period.