| Balance Sheets | 2026-03-31 | 2025-12-31 | 2025-09-30 | 2025-06-30 |
|---|---|---|---|---|
| Cash and cash equivalents | 329,462 | 307,531 | 330,843 | 371,435 |
| Prepaid expenses and other current assets | 9,739 | 7,662 | 9,131 | 14,040 |
| Total current assets | 339,201 | 315,193 | 339,974 | 385,475 |
| Property and equipment, net | 1,960 | 2,144 | 2,463 | 2,690 |
| Operating lease right-of-use assets | 7,391 | 8,125 | 8,849 | 9,563 |
| Deferred tax assets | NaN | 0 | 0 | 0 |
| Restricted cash, non-current | 860 | 860 | 860 | 860 |
| Other non-current assets | 482 | 482 | 482 | 478 |
| Total non-current assets | 10,693 | 11,611 | 12,654 | 13,591 |
| Total assets | 349,894 | 326,804 | 352,628 | 399,066 |
| Accounts payable | 4,299 | 5,875 | 10,503 | 12,198 |
| Accrued research and development | 4,611 | 4,329 | 9,544 | 10,929 |
| Deferred revenue, current | 1,630 | 2,664 | 2,685 | 5,100 |
| Restructuring liability | 8,585 | 13,303 | 17,614 | 30,330 |
| Lease liability, current | 2,893 | 2,886 | 2,879 | 2,853 |
| Other current liabilities | 10,499 | 11,786 | 8,211 | 6,397 |
| Total current liabilities | 32,517 | 40,843 | 51,436 | 67,807 |
| Deferred revenue, non-current | NaN | 0 | 0 | 0 |
| Lease liability, non-current | 4,761 | 5,487 | 6,203 | 6,928 |
| Total non-current liabilities | 4,761 | 5,487 | 6,203 | 6,928 |
| Total liabilities | 37,278 | 46,330 | 57,639 | 74,735 |
| Euro deferred shares, 22 nominal value authorized shares 10,000 at march31, 2026 and december31, 2025 issued and outstanding shares none at march31, 2026 and december31, 2025 | 0 | 0 | 0 | 0 |
| Ordinary shares, 0.01 par value authorized shares 100,000,000 at march31, 2026 and december31, 2025. issued and outstanding shares 53,077,225 and 53,832,982 at march31, 2026 and december31, 2025, respectively | 530 | 538 | 538 | 538 |
| Additional paid-in capital | 1,625,798 | 1,626,369 | 1,619,295 | 1,612,096 |
| Accumulated deficit | -1,313,712 | -1,346,433 | -1,324,844 | -1,288,303 |
| Total shareholders equity | 312,616 | 280,474 | 294,989 | 324,331 |
| Total liabilities and shareholders equity | 349,894 | 326,804 | 352,628 | 399,066 |
PROTHENA CORP PUBLIC LTD CO (PRTA)
PROTHENA CORP PUBLIC LTD CO (PRTA)