Intangible assets

9 Months Ended

Sep. 30, 2020

Goodwill and Intangible Assets Disclosure [Abstract]

Intangible assets

Intangible assets

	September 30, 2020		December 31, 2019
	(in thousands)
Utrophin program acquired	$	4,275	$	4,379
Discuva platform acquired	13,734		14,070
Option over non-financial assets	859		881
Other patents and licenses	142		432
Total intangible assets, gross	19,010		19,762
Less: Accumulated amortization	2,775		2,263
Impairment	5,134		4,379
Intangible assets, net of accumulated amortization	$	11,101	$	13,120

Amortization expense was $0.8 million and $1.0 million, for the periods ended September 31, 2020 and December 31, 2019, respectively.

We recognized impairment expenses of $0.9 million for the nine months ended September 30, 2020 related to our option over non-financial assets, which was written off in its entirety during the three months ended September 30, 2020.