Security	Date	Code	Shares	Price	A/D	Owned after	D/I	Nature of ownership
Common Stock^F1,F5,F4,F6	Jun 16, 2016	P	556,339	$0.56	A	3,604,266	I	See Footnotes
Common Stock^F2,F5,F4,F7	Jun 16, 2016	P	5,294	$0.56	A	34,291	I	See Footnotes
Common Stock^F3,F5,F4,F8	Jun 16, 2016	P	331,225	$0.56	A	2,149,902	I	See Footnotes

Table II — derivative securities

No Table II lines on this filing.

Explanation of responses

F1Represents shares of common stock of the Issuer ("Shares") purchased by OrbiMed Private Investments III, LP ("OPI III") in a secondary offering pursuant to a Subscription Agreement dated as of June 16, 2016 (the "Offering").
F2Represents Shares purchased by OrbiMed Associates III, LP ("OA III") in the Offering.
F3Represents Shares purchased by OrbiMed Asia Partners, L.P. ("OAP") in the Offering.
F4This report on Form 4 is jointly filed by OrbiMed Capital GP III LLC ("OrbiMed Capital"), OrbiMed Advisors LLC ("OrbiMed Advisors"), Samuel D. Isaly ("Isaly"), OrbiMed Advisors Limited ("OrbiMed Limited") and OrbiMed Asia GP, L.P. ("OrbiMed Asia"). Each of the reporting persons disclaims beneficial ownership of the securities reported herein for purposes of Rule 16a-1(a) under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), except to the extent of its or his pecuniary interest therein, if any. This report shall not be deemed an admission that the reporting persons are beneficial owners for the purpose of Section 16 of the Exchange Act, or for any other purpose.
F5The reporting persons have designated two representatives, currently Jonathan Wang and Peter Thompson, all of whom are employees of OrbiMed Advisors, to serve on the Issuer's board of directors. Each such representative disclaims beneficial ownership of the securities reported herein, except to the extent of his pecuniary interest therein, if any. This report shall not be deemed an admission that any of them are beneficial owners for the purpose of Section 16 of the Exchange Act, or for any other purpose.
F6These Shares are held of record by OPI III and may be deemed to be indirectly beneficially owned by OrbiMed Capital, OrbiMed Advisors and Isaly. OrbiMed Capital is the sole general partner of OPI III. OrbiMed Advisors, a registered adviser under the Investment Advisers Act of 1940, as amended, is the sole managing member of OrbiMed Capital. Pursuant to those relationships, OrbiMed Capital and OrbiMed Advisors have discretionary investment management authority with respect to the assets of OPI III. Such authority includes the power to vote and otherwise dispose of the securities held by OPI III. Isaly, a natural person, is the managing member of, and holder of a controlling interest in, OrbiMed Advisors. As a result, Isaly, OrbiMed Advisors and OrbiMed Capital share power to direct the vote and to direct the disposition of the securities held by OPI III.
F7These Shares are held of record by OA III and may be deemed to be indirectly beneficially owned by OrbiMed Advisors and Isaly. OrbiMed Advisors is the sole general partner of OA III, and Isaly is the managing member of, and holder of a controlling interest in, OrbiMed Advisors. As a result, Isaly and OrbiMed Advisors share power to direct the vote and to direct the disposition of the securities held by OA III.
F8These Shares are held of record by OAP and may be deemed to be indirectly beneficially owned by OrbiMed Asia and OrbiMed Limited. OrbiMed Asia is the sole general partner of OAP and OrbiMed Limited is the sole general partner of OrbiMed Asia. As a result, OrbiMed Asia has the power to direct the vote and to direct the disposition of the securities held by OAP and such power is exercised through OrbiMed Limited.