| In millions, except per share items | Dec-31-22 | Dec-31-21 | Dec-31-20 | Dec-31-19 | Dec-31-18 | Dec-31-17 | Dec-31-16 |
| | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | S-1/A |
| License revenue - related party | 15.9 | 37.7 | 15.6 | 13.3 | | | |
| License revenue - related party growth | -57.8% | 142.2% | 17.1% | | | | |
| Operating expenses: | | | | | | | |
| General and administrative | 46.6 | 43.8 | 44.2 | 46.7 | 44.5 | 9.3 | 6.0 |
| Research and development | 85.7 | 66.7 | 33.9 | 24.9 | 33.6 | 22.4 | 14.0 |
| Total operating expenses | 132.3 | 110.5 | 78.1 | 71.6 | 78.1 | 31.7 | 20.1 |
| Loss from operations | -116.4 | -72.8 | -62.6 | -58.3 | -78.1 | -31.7 | -20.1 |
| Operating margin | -730.9% | -193.0% | -401.9% | -438.4% | | | |
| |
| Other non-operating income (expense): | | | | | | | |
| Foreign currency gain (loss) | 9.5 | 6.3 | 3.4 | 3.2 | -3.8 | 1.7 | -0.3 |
| Interest income | 0.8 | 0.2 | 1.3 | 0.4 | 0.1 | 0.0 | 0.0 |
| Interest expense | -4.9 | -0.3 | -0.1 | 0.0 | 0.0 | 0.0 | 0.0 |
| Fair value adjustments | 0.4 | -0.4 | | | | | |
| Net loss | -129.6 | -79.6 | -58.0 | -54.7 | -82.9 | -31.0 | -19.8 |
| |
| Other comprehensive income (loss): | | | | | | | |
| Foreign currency translation (loss) gain | 8.7 | 2.2 | -3.1 | -2.1 | 2.3 | -1.4 | |
| Total comprehensive loss | -120.9 | -77.3 | -61.1 | -56.8 | -80.5 | -32.4 | -20.2 |
| Net loss | -129.6 | -79.6 | -58.0 | -54.7 | -84.7 | -31.9 | |
| |
| Basic net loss per ordinary share | ($2.87) | ($1.80) | ($1.54) | ($1.65) | ($4.47) | ($3.72) | |
| Diluted net loss per ordinary share | ($2.87) | ($1.80) | ($1.54) | | | | |
| |
| Weighted-average number of ordinary shares outstanding, basic | 45.2 | 44.1 | 37.7 | 33.2 | 18.9 | 8.6 | |
| Weighted-average number of ordinary shares outstanding, diluted | 45.2 | 44.1 | 37.7 | | | | |