GAIN FROM SALE OF PRIORITY REVIEW VOUCHER	9 Months Ended
Sep. 30, 2020
Goodwill And Intangible Assets Disclosure [Abstract]
GAIN FROM SALE OF PRIORITY REVIEW VOUCHER	4. GAIN FROM SALE OF PRIORITY REVIEW VOUCHER In February 2020, the Company entered into an agreement with Vifor (International) Ltd. to sell the rare pediatric disease Priority Review Voucher (“PRV”) it received from the FDA in connection with the approval of VYONDYS 53. Following the early termination of the applicable waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended, in March 2020, the Company completed its sale of the PRV and received proceeds of $108.1 million, net of commission, which was recorded as a gain from sale of the PRV as it did not have a carrying value at the time of the sale.

GAIN FROM SALE OF PRIORITY REVIEW VOUCHER

9 Months Ended

Sep. 30, 2020

Goodwill And Intangible Assets Disclosure [Abstract]

GAIN FROM SALE OF PRIORITY REVIEW VOUCHER

4. GAIN FROM SALE OF PRIORITY REVIEW VOUCHER

In February 2020, the Company entered into an agreement with Vifor (International) Ltd. to sell the rare pediatric disease Priority Review Voucher (“PRV”) it received from the FDA in connection with the approval of VYONDYS 53. Following the early termination of the applicable waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended, in March 2020, the Company completed its sale of the PRV and received proceeds of $108.1 million, net of commission, which was recorded as a gain from sale of the PRV as it did not have a carrying value at the time of the sale.