| Name | Ownership | Shares Owned | sole voting power | shared voting power | Signature | Title | CIK |
|---|---|---|---|---|---|---|---|
| RA Capital Management, L.P. | 32% | 39,739,850 | 0 | 39,739,850 | /s/ Peter Kolchinsky | By Peter Kolchinsky, Manager | 0001346824 |
| Peter Kolchinsky | 32% | 39,739,850 | 0 | 39,739,850 | /s/ Peter Kolchinsky | Peter Kolchinsky | 0001384859 |
| Rajeev Shah | 32% | 39,739,850 | 0 | 39,739,850 | /s/ Rajeev Shah | Rajeev Shah | 0001619841 |
| RA Capital Healthcare Fund, L.P. | 30% | 37,820,713 | 0 | 37,820,713 | /s/ Peter Kolchinsky | By RA Capital Healthcare Fund GP, LLC, its General Partner, By Peter Kolchinsky, Manager | 0001315082 |