| REVENUES (Tables)
 | 9 Months Ended | 
| Sep. 30, 2024 | 
|---|
| REVENUES |  | 
| Schedule of revenues disaggregated by category | Revenues disaggregated by category were as follows (in thousands): 
|  |  |  |  |  |  |  |  |  |  |  |  |  |  
|  |  | Three Months Ended September 30,  |  | Nine Months Ended September 30,  |  
|  |  | 2024 |      | 2023 |  | 2024 |      | 2023 |  
| Product sales: |  |  |  |  |  |  |  |  |  |  |  |  |  
| Gross product sales |  | $ | 56,322  |  | $ | 38,585  |  | $ | 143,728  |  | $ | 105,239  |  
| Discounts and allowances |  |  | (17,395) |  |  | (11,456) |  |  | (45,348) |  |  | (30,484) |  
| Total product sales, net |  |  |  38,927 |  |  |  27,129 |  |  |  98,380 |  |  |  74,755 |  
| Revenues from collaborations: |  |  |  |  |  |  |  |  |  |  |  |  |  
| License revenue |  |  |  10,000 |  |  |  — |  |  |  10,000 |  |  |  — |  
| Milestone revenue |  |  |  — |  |  |  75 |  |  |  — |  |  |  75 |  
| Delivery of drug supplies, royalty and others |  |  | 6,380  |  |  | 930  |  |  | 13,302  |  |  | 5,260  |  
| Total revenues from collaborations |  |  |  16,380 |  |  |  1,005 |  |  |  23,302 |  |  |  5,335 |  
| Government contracts |  |  |  — |  |  |  — |  |  |  — |  |  |  1,000 |  
| Total revenues |  | $ |  55,307 |  | $ |  28,134 |  | $ |  121,682 |  | $ |  81,090 |  | 
| Schedule of product revenue allowance and reserve categories | 
|  |  |  |  |  |  |  |  |  |  |  |  |  |  
|  |  | Chargebacks, |  | Government |  |  |  |  |  
|  |  | Discounts and |  | and Other |  |  |  |  |  
|  |  | Fees |  | Rebates |  | Returns |  | Total |  
| Balance as of January 1, 2024 |      | $ |  8,236 |  | $ |  3,517 |  | $ |  3,931 |  | $ |  15,684 |  
| Provision related to current period sales |  |  |  34,565 |  |  |  9,167 |  |  |  884 |  |  |  44,616 |  
| Credit or payments made during the period |  |  |  (31,363) |  |  |  (6,441) |  |  |  (304) |  |  |  (38,108) |  
| Balance as of September 30, 2024 |   | $ |  11,438 |  | $ |  6,243 |  | $ |  4,511 |  | $ |  22,192 |   
|  |  |  |  |  |  |  |  |  |  |  |  |  |  
|  |  | Chargebacks, |  | Government |  |  |  |  |  |  |  
|  |  | Discounts and |  | and Other |  |  |  |  |  |  |  
|  |  | Fees |  | Rebates |  | Returns |  | Total |  
| Balance as of January 1, 2023 |      | $ |  6,213 |  | $ |  2,636 |  | $ |  3,296 |  | $ |  12,145 |  
| Provision related to current period sales |  |  |  23,150 |  |  |  5,932 |  |  |  623 |  |  |  29,705 |  
| Credit or payments made during the period |  |  |  (21,504) |  |  |  (5,631) |  |  |  (172) |  |  |  (27,307) |  
| Balance as of September 30, 2023 |   | $ |  7,859 |  | $ |  2,937 |  | $ |  3,747 |  | $ |  14,543 |  | 
| Schedule of revenues from product sales disaggregated by customers |  
|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
|  |  | Three Months Ended September 30,  |  |  | Nine Months Ended September 30,  |  
|  |  | 2024 |      | 2023 |  |  | 2024 |      | 2023 |  
| McKesson Corporation |  |  | 43% |  |  | 49% |  |  |  | 44% |  |  | 46% |  
| Cencora Inc. (formerly ASD Healthcare) |  |  | 19% |  |  | 18% |  |  |  | 20% |  |  | 20% |  
| Cardinal Health, Inc. |  |  | * |  |  | 28% |  |  |  | 15% |  |  | 27% |  
| Kissei |  |  | 23% |  |  | * |  |  |  | 14% |  |  | * |  |