Security	Date	Code	Shares	Price	A/D	Owned after	D/I
Common Stock, $0.0001 par value per share^F1,F5,F2	Jun 18, 2018	J	1,105,391	—	D	498,025	D
Common Stock, $0.0001 par value per share^F1,F5,F3	Jun 18, 2018	J	705,863	—	D	318,021	D
Common Stock, $0.0001 par value per share^F1,F5,F4	Jun 18, 2018	J	188,746	—	D	85,038	D

Table II — derivative securities

Security	Conv. / exercise price	Date	Code	Shares	A/D	Exercisable	Expires	Underlying	Underlying shares	Owned after	D/I
Warrants^F5,F2	—	Jun 18, 2018	J	1,105,391	A	—	—	Common Stock, $0.0001 par value per share	1,105,391	1,105,391	D
Warrants^F5,F3	—	Jun 18, 2018	J	705,863	A	—	—	Common Stock, $0.0001 par value per share	705,863	705,863	D
Warrants^F5,F4	—	Jun 18, 2018	J	188,746	A	—	—	Common Stock, $0.0001 par value per share	188,746	188,746	D

Explanation of responses

F1This Form 4 is filed jointly by Biotechnology Value Fund, L.P. ("BVF"), Biotechnology Value Fund II, L.P. ("BVF2"), Biotechnology Value Trading Fund OS LP ("Trading Fund OS"), BVF Partners OS Ltd. ("Partners OS"), BVF Partners L.P. ("Partners"), BVF Inc. and Mark N. Lampert (collectively, the "Reporting Persons"). Each of the Reporting Persons is a member of a Section 13(d) group that collectively owned more than 10% of the Issuer's outstanding shares of Common Stock. Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein except to the extent of his or its pecuniary interest therein.
F2Securities owned directly by BVF. As the general partner of BVF, Partners may be deemed to beneficially own the securities owned directly by BVF. As the investment adviser and general partner of Partners, BVF Inc. may be deemed to beneficially own the securities owned directly by BVF. As a director and officer of BVF Inc., Mr. Lampert may be deemed to beneficially own the securities owned directly by BVF.
F3Securities owned directly by BVF2. As the general partner of BVF2, Partners may be deemed to beneficially own the securities owned directly by BVF2. As the investment adviser and general partner of Partners, BVF Inc. may be deemed to beneficially own the securities owned directly by BVF2. As a director and officer of BVF Inc., Mr. Lampert may be deemed to beneficially own the securities owned directly by BVF2.
F4Securities owned directly by Trading Fund OS. As the general partner of Trading Fund OS, Partners OS may be deemed to beneficially own the securities owned directly by Trading Fund OS. As the investment manager of Trading Fund OS and the sole member of Partners OS, Partners may be deemed to beneficially own the securities owned directly by Trading Fund OS. As the investment adviser and general partner of Partners, BVF Inc. may be deemed to beneficially own the securities owned directly by Trading Fund OS. As a director and officer of BVF Inc., Mr. Lampert may be deemed to beneficially own the securities owned directly by Trading Fund OS.
F5Pursuant to an agreement between the Issuer and the Reporting Persons, the Reporting Persons agreed to exchange in the aggregate 2,000,000 shares of the Company's Common Stock for pre-funded warrants (the "Exchange Warrants") to purchase an aggregate of 2,000,000 shares of Common Stock, subject to adjustment in the event of stock splits, recapitalizations and other similar events affecting Common Stock, with an exercise price of $0.0001 per share. The Exchange Warrants will expire twenty years from the date of issuance. The Exchange Warrants are exercisable at any time prior to expiration except that the Exchange Warrants cannot be exercised by the Reporting Persons if, after giving effect thereto, the Reporting Persons would beneficially own, as determined in accordance with Section 13(d) of the Securities Exchange Act of 1934, more than 9.99% of Common Stock, subject to certain exceptions.