FIRST AMENDMENT TO SECOND AND RESTATED REGISTRATION RIGHTS AGREEMENT

Capitalized terms not otherwise defined herein shall have the meanings specified for such terms in the Registration Rights Agreement.

WHEREAS, the Avista Holders, PGS and Levant collectively constitute Requesting Holders;

NOW THEREFORE, the undersigned hereby agree as follows:

1.             The first sentence of Section 2.1(i) of the Registration Rights Agreement is hereby amended and restated to read in its entirety as follows:

(i)                                     In lieu of any of the Demand Registration and if the Company has established a “shelf offering” of newly issued shares of Common Stock (the “Company Shelf Shares”) under the Securities Act to be made on a continuous basis pursuant to Rule 415 on Form S-3 (the “Company Shelf”), each of the Avista Holders and PGS may issue a Demand Request for the Company to sell Company Shelf Shares and use the proceeds from such sale to purchase all or any portion of (i) t he Registrable Shares held by such Requesting Holder (the “Shelf Funded Repurchase”) at a price equal to the price at which the Company Shelf Shares were sold less any underwriting discounts and commission (the “Net Price”) or (ii) to purchase all or any portion of any warrants to purchase Registrable Shares held by such Requesting Holder at a price per Registrable Share underlying the warrant (“Warrant Share”) equal to the Net Price less the applicable exercise price per Warrant Share.