Transactions Table

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Explanation of Responses:

Id	Content
F1	Represents a cross-trade of securities of the Issuer among certain private funds managed by Redmile (the "Redmile Funds"). The reported transactions occurred simultaneously at the market open, at which time the price of the Issuer's common stock was $22.49, and therefore the reported transactions resulted in no profit to any of the Redmile Funds, Redmile or Jeremy Green and resulted in no change in the aggregate beneficial ownership of Redmile and Mr. Green.
F2	The non-voting common stock is convertible into shares of the Issuer's common stock at any time, in accordance with the terms of the Issuer's Amended and Restated Certificate of Incorporation at any time and from time to time at the holder's election on a 1-for-1 basis. Such conversion rate is reflected in the amount listed under Column 7.
F3	The Issuer's Amended and Restated Certificate of Incorporation provides that the holder may not convert any shares of non-voting common stock if, after giving effect to the attempted conversion, the holder and its affiliates would collectively beneficially own more than 4.99% of the number of shares of Common Stock outstanding after giving effect to such attempted conversion, which percentage may be changed at a holder's election upon 61 days' notice to the Issuer. The non-voting common stock has no expiration date. The non-voting Common Stock held by the Redmile Funds may be deemed beneficially owned by Redmile as the investment manager of such Redmile Funds.
F4	The pre-funded warrants to purchase common stock of the Issuer have no expiration date.
F5	The common stock, non-voting common stock and pre-funded warrants of the Issuer reported herein are directly owned by the Redmile Funds, none of which individually is a 10% owner, and may be deemed beneficially owned by Redmile as investment manager of the Redmile Funds.
F6	The reported securities may also be deemed beneficially owned by Jeremy Green as the principal of Redmile. Each of Redmile and Mr. Green (collectively, the "Reporting Persons") disclaims beneficial ownership of the reported securities except to the extent of their pecuniary interest therein. This report shall not be deemed an admission that such Reporting Persons are a beneficial owner of such securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose.
F7	Mr. Michael Lee, a member of the board of directors of the Issuer and a managing director of Redmile, was elected to the board of the Issuer as a representative of Redmile. As a result, the Reporting Persons are directors by deputization for purposes of Section 16 of the Securities Exchange Act of 1934, as amended.