Filing Details

Items 3 and 5 of the Statement are hereby amended to the extent hereinafter expressly set forth. Except as amended hereby, the original disclosure set forth in the Statement shall remain unchanged. All capitalized terms used and not expressly defined herein have the respective meanings ascribed to such terms in the Statement. 

Item 3. Source and Amount of Funds or Other Consideration

Item 3 of the Statement is hereby amended to add the following:

Since December 18, 2017, the Reporting Persons have expended an aggregate of approximately $6,700,000 to purchase 290,000 shares of the Issuer’s Common Stock. Such purchases were effected through the open market. The Common Stock was acquired in the ordinary course of business. Subject to the following paragraph, Tang Capital Partners, LP used its own funds for the purchases, none of which were borrowed or otherwise obtained from any other source.

Tang Capital Partners, LP maintains commingled margin accounts with various financial institutions, which may extend margin credit to Tang Capital Partners, LP as and when required, to open or carry positions in the margin accounts, subject to applicable federal margin regulations, stock exchange rules and credit policies. In such instances, the positions held in the margin accounts are pledged as collateral security for the repayment of debit balances in the accounts. The margin accounts may from time to time have debit balances. Since multiple different securities are held in the margin accounts, it is not possible to determine the amounts, if any, of margin used to purchase the shares of Common Stock reported herein.

Tang Capital Partners, LP is the beneficial owner of 12,492,338 shares of the Issuer’s Common Stock. Tang Capital Partners, LP shares voting and dispositive power over such shares of Common Stock with Tang Capital Management, LLC and Kevin C. Tang. Subject to the arrangements described in Item 6 of this Statement, the shares reported as beneficially owned by the Reporting Persons include a total of 154,285 shares of Common Stock that are held of record by Odonate Holdings, LLC (“Holdings”). Holdings has granted a proxy to Tang Capital Partners, LP giving Tang Capital Partners, LP the authority to vote such shares.

The percentages used herein are based upon 26,891,691 shares of Common Stock outstanding as set forth in the Issuer’s Quarterly Report on Form 10-Q that was filed with the SEC on July 30, 2018.

Tang Capital Management, LLC, as the general partner of Tang Capital Partners, LP, may be deemed to beneficially own the shares of the Issuer’s Common Stock owned by Tang Capital Partners, LP. Tang Capital Management, LLC shares voting and dispositive power over such shares with Tang Capital Partners, LP and Kevin C. Tang.

Kevin C. Tang, as the manager of Tang Capital Management, LLC, may be deemed to beneficially own the shares of the Issuer’s Common Stock beneficially owned by Tang Capital Partners, LP. Kevin C. Tang shares voting and dispositive power over such shares with Tang Capital Partners, LP and Tang Capital Management, LLC.

(c)          The Reporting Persons have engaged in the following transactions in the Issuer’s Common Stock during the last 60 days.

¹ The price reported is a weighted-average price. These shares were purchased in multiple transactions at prices ranging from $18.25 to $19.00. The Reporting Persons undertake to provide the Issuer, any security holder of the Issuer or the SEC staff, upon request, all information regarding the number of shares sold at each price within the ranges set forth in Footnotes 1 through 11 herein.

² The price reported is a weighted-average price. These shares were purchased in multiple transactions at prices ranging from $18.55 to $19.22.

³ The price reported is a weighted-average price. These shares were purchased in multiple transactions at prices ranging from $18.81 to $19.68.

⁴ The price reported is a weighted-average price. These shares were purchased in multiple transactions at prices ranging from $19.99 to $20.00.

⁵ The price reported is a weighted-average price. These shares were purchased in multiple transactions at prices ranging from $18.65 to $18.88.

⁶ The price reported is a weighted-average price. These shares were purchased in multiple transactions at prices ranging from $19.57 to $20.00.

⁷ The price reported is a weighted-average price. These shares were purchased in multiple transactions at prices ranging from $18.95 to $19.94.

⁸ The price reported is a weighted-average price. These shares were purchased in multiple transactions at prices ranging from $19.95 to $20.00.

⁹ The price reported is a weighted-average price. These shares were purchased in multiple transactions at prices ranging from $19.01 to $19.39.

¹⁰ The price reported is a weighted-average price. These shares were purchased in multiple transactions at prices ranging from $18.71 to $19.18.

¹¹ The price reported is a weighted-average price. These shares were purchased in multiple transactions at prices ranging from $19.28 to $19.71.

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