| 13.43% | % of Shares Held by All Insider |
| 73.70% | % of Shares Held by Institutions |
| 85.13% | % of Float Held by Institutions |
| 121 | Number of Institutions Holding Shares |
| Holder | Shares | Date Reported | % Out | Value |
|---|---|---|---|---|
| TRV GP II, LLC | 10,230,349 | Dec 30, 2018 | 31.35% | 34,476,276 |
| TRV GP III, LLC | 3,048,780 | Dec 30, 2018 | 9.34% | 10,274,388 |
| Wellington Management Company, LLP | 1,510,754 | Dec 30, 2018 | 4.63% | 5,091,240 |
| Blackrock Inc. | 1,065,339 | Dec 30, 2018 | 3.27% | 3,590,192 |
| FMR, LLC | 1,007,115 | Dec 30, 2018 | 3.09% | 3,393,977 |
| JP Morgan Chase & Company | 620,148 | Dec 30, 2018 | 1.90% | 2,089,898 |
| Pharmstandard International S.A. | 565,063 | Sep 29, 2018 | 1.73% | 3,672,909 |
| Omega Fund Management (US) Inc. | 529,965 | Dec 30, 2018 | 1.62% | 1,785,982 |
| Vanguard Group, Inc. (The) | 477,871 | Dec 30, 2018 | 1.46% | 1,610,425 |
| Dimensional Fund Advisors LP | 456,865 | Dec 30, 2018 | 1.40% | 1,539,635 |
| Holder | Shares | Date Reported | % Out | Value |
|---|---|---|---|---|
| Fidelity Select Portfolios - Biotechnology | 715,474 | Nov 29, 2018 | 2.19% | 3,090,847 |
| Vanguard Total Stock Market Index Fund | 444,633 | Sep 29, 2018 | 1.36% | 2,890,114 |
| iShares Russell 2000 ETF | 374,697 | Nov 29, 2018 | 1.15% | 1,618,691 |
| iShares NASDAQ Biotechnology ETF | 367,769 | Nov 29, 2018 | 1.13% | 1,588,762 |
| DFA U.S. Small Cap Series | 207,557 | Oct 30, 2018 | 0.64% | 838,530 |
| iShares Russell 2000 Growth ETF | 149,598 | Nov 29, 2018 | 0.46% | 646,263 |
| Fidelity Growth Company Fund | 146,818 | Nov 29, 2018 | 0.45% | 634,253 |
| Bridgeway Funds Inc-Ultra Small Company Market Fund | 115,000 | Sep 29, 2018 | 0.35% | 747,500 |
| Vanguard Extended Market Index Fund | 96,348 | Sep 29, 2018 | 0.30% | 626,262 |
| Hartford Smallcap Growth HLS Series | 89,780 | Jun 29, 2018 | 0.28% | 687,714 |