Shareholders' Equity (Tables)

6 Months Ended

Jun. 30, 2019

Share-based Payment Arrangement [Abstract]

Schedule of Black-Scholes-Merton option pricing model assumptions

	Six Months Ended June 30,
	2019			2018
Expected volatility		57.5	%		57.19 - 61.12	%
Risk-free rate		2.22	%		2.74% - 2.83	%
Dividend yield		—	%		—	%
Expected term (in years)		6.11			6.11
Share price	$	5.37		$	26.88 - $28.75

Schedule of employee options activity

	Number			Average exercise price		Average remaining contractual life (in years)		Aggregate intrinsic value (in thousands)
Options outstanding at the beginning of the period		72,655		$	47.70		6.37	$	114
Granted		12,425			5.37
Exercised		—			—
Forfeited		(5,371	)		45.93
Options outstanding at the end of the period		79,709		$	41.19		6.80	$	393
Options exercisable at the end of the period		43,868		$	56.49		4.96	$	—

Schedule of employee RSUs activity

	Number of shares underlying outstanding RSUs			Weighted average grant date fair value
Unvested RSUs at the beginning of the period		26,093		$	48.78
Granted		87,436			4.69
Vested		(16,656	)		9.82
Forfeited		(6,599	)		17
Unvested RSUs at the end of the period		90,274		$	37.49

Schedule of options and RSUs outstanding

Range of exercise price	Options and RSUs outstanding as of June 30, 2019		Weighted average remaining contractual life (years) (1)		Options outstanding and exercisable as of June 30, 2019		Weighted average remaining contractual life (years) (1)
RSUs only	90,274		—		—		—
$5.37		12,425		9.75		—		—
$20.42 - $33.75		39,220		6.85		19,570		4.86
$37.14 - $38.75		12,740		4.44		12,740		4.44
$50 - $52.5		11,395		6.20		7,697		5.36
$182.5 - $524.25		3,929		6.40		3,861		6.40
		169,983		6.80		43,868		4.96

(1) Calculation of weighted average remaining contractual term does not include the RSUs that were granted, which have an indefinite contractual term.

Schedule of warrants outstanding and exercisable

Issuance date	Warrants outstanding		Exercise price per warrant		Warrants outstanding and exercisable		Contractual term
	(number)				(number)
December 31, 2015 (1)		4,771	$	7.500		4,771	See footnote (1)
November 1, 2016 (2)		97,496	$	118.750		97,496	November 1, 2021
December 28, 2016 (3)		1,908	$	7.500		1,908	See footnote (1)
November 20, 2018 (4)		126,839	$	7.500		126,839	November 20, 2023
November 20, 2018 (5)		106,680	$	9.375		106,680	November 15, 2023
February 25, 2019 (6)		45,600	$	7.187		45,600	February 21, 2024
April 5, 2019 (7)		408,457	$	5.140		408,457	October 7, 2024
April 5, 2019 (8)		49,015	$	6.503		49,015	April 3, 2024
June 5, 2019 and June 6, 2019 (9)		1,464,665	$	7.500		1,464,665	June 5, 2024
June 5, 2019 (10)		87,880	$	9.375		87,880	June 5, 2024
June 12, 2019 (11)		416,667	$	6.000		416,667	December 12, 2024
June 10, 2019 (12)		50,000	$	7.500		50,000	June 10, 2024
		2,859,978				2,859,978

(1) Represents warrants for ordinary shares issuable upon an exercise price of $7.5 per share, which were granted on December 31, 2015 to Kreos Capital V (Expert) Fund Limited, or Kreos, in connection with a loan made by Kreos to us and are currently exercisable (in whole or in part) until the earlier of (i) December 30, 2025 or (ii) immediately prior to the consummation of a merger, consolidation, or reorganization of us with or into, or the sale or license of all or substantially all the assets or shares of us to, any other entity or person, other than a wholly-owned subsidiary of us, excluding any transaction in which our shareholders prior to the transaction will hold more than 50% of the voting and economic rights of the surviving entity after the transaction. None of these warrants had been exercised as of June 30, 2019.

(2) Represents warrants issued as part of our follow-on offering in November 2016. At any time, the board of directors may reduce the exercise price of the warrants to any amount and for any period of time it deems appropriate.

(3) Represents common warrants that were issued as part of the $8.0 million drawdown under the Loan Agreement which occurred on December 28, 2016. See footnote 1 for exercisability terms.

(4) Represents common warrants that were issued as part of our follow-on offering in November 2018. As of June 30, 2019, warrants to purchase an aggregate 1,651,537 ordinary shares had been exercised.

(5) Represents common warrants that were issued to the underwriters as compensation for their role in our follow-on offering in November 2018.

(6) Represents warrants that were issued to the exclusive placement agent as compensation for its role in our follow-on offering in February 2019.

(7) Represents warrants that were issued to certain institutional purchasers in a private placement in our registered direct offering of ordinary shares in April 2019.

(8) Represents warrants that were issued to the placement agent as compensation for its role in our April 2019 registered direct offering.

(9) Represents warrants that were issued to certain institutional investors in a warrant exercise agreement on June 5, 2019 and June 6, 2019, respectively.

(10) Represents warrants that were issued to the placement agent as compensation for its role in our June 2019 warrant exercise agreement and concurrent private placement of warrants.

(11) Represents warrants that were issued to certain institutional investors in a warrant exercise agreement in June 2019.

(12) Represents warrants that were issued to the placement agent as compensation for its role in our June 2019 registered direct offering and concurrent private placement of warrants.

Schedule of non-cash share-based compensation expense

	Six Months Ended June 30,
	2019		2018
Cost of revenues	$	7	$	7
Research and development, net		124		203
Sales and marketing		126		300
General and administrative		376		1,309
Total	$	633	$	1,819