The Company has an investment in NeuBase common stock with restrictions on the sale or transfer of the shares. Fair value is determined using alternative pricing sources and models utilizing market observable inputs. The Company reports the restricted equity securities as non-marketable equity securities on the balance sheet, and determines current or non-current classification based on the expected duration of the restriction.

The Company recorded a net unrealized loss of $0.9 million in other expense for the year ended December 31, 2021. The carrying value is measured as the total initial cost, less the cumulative net unrealized loss. The carrying value of the non-marketable equity securities as of December 31, 2021, is summarized below (in thousands).


Initial cost as of April 26, 2021	$	1,759
Change in fair value		(892	)
Balance as of December 31, 2021	$	867