RELATED PARTY TRANSACTIONS (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
Jul. 31, 2016	Dec. 31, 2019	Dec. 31, 2018
MSK \| MSK License Agreement, the CD33 License Agreement, CTA, CFAs, SRA and MDSA
Related party transactions
Expenses		$ 6,832	$ 5,761
Due to related parties		4,171	4,475
Weco Group \| Lease Agreement
Related party transactions
Expenses		$ 0	$ 44
Lease payable per month	$ 4
Notice period to terminate lease	3 months
Future rent commitment	$ 12

Carrying amount as of the balance sheet date of obligations due all related parties.

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