| FMR LLC | 12,349,256 | $1.4bn | 0.1% |
| BAKER BROS. ADVISORS LP | 8,657,242 | $992.7m | 5.0% |
| Avoro Capital Advisors LLC | 7,474,747 | $857.1m | 7.7% |
| PRICE T ROWE ASSOCIATES INC /MD/ | 7,112,980 | $815.6m | 0.1% |
| T. Rowe Price Investment Management, Inc. | 6,257,261 | $717.5m | 0.5% |
| BlackRock, Inc. | 5,538,210 | $635.1m | 0.0% |
| BVF INC/IL | 3,872,052 | $444.0m | 11.4% |
| WELLINGTON MANAGEMENT GROUP LLP | 3,675,028 | $421.4m | 0.1% |
| VANGUARD PORTFOLIO MANAGEMENT LLC | 2,992,193 | $343.1m | 0.0% |
| Siren, L.L.C. | 2,935,830 | $336.7m | 6.8% |
| VANGUARD CAPITAL MANAGEMENT LLC | 2,932,378 | $336.3m | 0.0% |
| Atlas Venture Life Science Advisors, LLC | 2,847,541 | $326.5m | 37.1% |
| STATE STREET CORP | 2,737,226 | $313.9m | 0.0% |
| GEODE CAPITAL MANAGEMENT, LLC | 1,816,331 | $208.3m | 0.0% |
| Capital Research Global Investors | 1,388,881 | $159.3m | 0.0% |
| GOLDMAN SACHS GROUP INC | 1,187,333 | $136.2m | 0.0% |
| UBS Group AG | 1,007,777 | $115.6m | 0.0% |
| Driehaus Capital Management LLC | 919,233 | $105.4m | 0.6% |
| Merck & Co., Inc. | 772,165 | $88.5m | 16.8% |
| NORGES BANK | 757,246 | $86.8m | 0.0% |
| FEDERATED HERMES, INC. | 749,398 | $85.9m | 0.1% |
| DIMENSIONAL FUND ADVISORS LP | 745,152 | $85.4m | 0.0% |
| FRONTIER CAPITAL MANAGEMENT CO LLC | 740,866 | $85.0m | 0.8% |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC | 736,866 | $84.5m | 0.0% |
| ALLIANCEBERNSTEIN L.P. | 981,521 | $81.8m | 0.0% |