Page 6 of 7 – SEC Filing
| Item 3. | If this statement is filed pursuant to rule 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a: |
| (a) | [ ] Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o). |
| (b) | [ ] Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c). |
| (c) | [ ] Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c). |
| (d) | [ ] Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8). |
| (e) | [ X ] An investment adviser in accordance with section 240.13d-1(b)(1)(ii)(E) as to EcoR1. |
| (f) | [ ] An employee benefit plan or endowment fund in accordance with section 240.13d-1(b)(1)(ii)(F). |
| (g) | [ X ] A parent holding company or control person in accordance with 240.13d-1(b)(1)(ii)(G) as to Mr. Nodelman. |
| (h) | [ ] A savings association as defined in section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813). |
| (i) | [ ] A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3). |
| (j) | [ ] Group, in accordance with section 240.13d-1(b)(1)(ii)(J). |
| Item 4. | Ownership. |
See Items 5-9 and 11 of the cover page for each Filer.
| Item 5. | Ownership of Five Percent or Less of a Class |
If this statement is being filed to report the fact that
as of the date hereof the reporting person has ceased to be the beneficial owner of more than five percent of the class of securities,
check the following [ ].
| Item 6. | Ownership of More than Five Percent on Behalf of Another Person. |
The funds managed by EcoR1, including Qualified Fund, hold
the Stock for the benefit of their investors and have the right to receive or the power to direct the receipt of dividends from,
or the proceeds from the sale of, the Stock.
| Item 7. | Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on By the Parent Holding Company. |
Not applicable.
| Item 8. | Identification and Classification of Members of the Group. |
EcoR1 is the general partner and investment adviser of investment
funds, including Qualified Fund. Mr. Nodelman is the control person of EcoR1.
| Item 9. | Notice of Dissolution of Group. |
Not applicable.
| Item 10. | Certification. |
Certification of EcoR1 and Mr. Nodelman:
By signing below I certify that, to the best of my knowledge
and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired
and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and
were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect.
Certification of Qualified Fund:
By signing below I certify that, to the best of my knowledge
and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing
or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant
in any transaction having that purpose or effect.
SIGNATURE
After reasonable inquiry and to the best of my knowledge
and belief, I certify that the information set forth in this statement is true, complete and correct.
Dated: May 10, 2017
| EcoR1 CAPITAL, LLC By: /s/ Oleg Nodelman, Manager
|
/s/ Oleg Nodelman |
| EcoR1 CAPITAL FUND QUALIFIED, L.P. By: EcoR1 Capital, LLC, General Partner By: /s/ Oleg Nodelman, Manager
|
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