B. Section 5.9shall be amended by deleting the entire text thereof and replacing it with the following:     5.9 Equity Holding Period. A holding period was imposed on Glenveigh with respect toany PTI Ordinary Shares granted to Glenveigh pursuant to Section 5.1.2. Such holding period shallexpire upon the Amendment Effective Date. During the holding period, Glenveigh agreed not todispose of or agree to dispose of, directly or indirectly, any such PTI Ordinary Shares or doanything with the same or substantially the same economic effect (including a derivativestransaction), without the prior written consent of Protherics plc. Following the AmendmentEffective Date, the PTI Ordinary Shares issued to Glenveigh pursuant to Section 5.1.2 will befreely transferable under the rules of the London Stock Exchange, the Listing Rules of the UKFinancial Services Authority and English law, subject only to the restrictions contained in thisAgreement and as referred to in Article 202 of the Articles of Association of Protherics plc.     C. Section 5.11shall be amended by deleting the entire text thereof and replacing it with the following:     5.11 Reserved.     D. Section 6.2 shall be amended by deleting the strike-through text as indicated below.     6.2 Patent Filing, Prosecution and Maintenance. Glenveigh shall own or Control(as applicable) patents or patent applications within the Licensed Patents in the Territory.During the term of this Agreement, Protherics shall be responsible for, and shall diligentlycarry out and shall bear all costs (including attorneys’ fees) for the preparation, filing,prosecution, maintenance and extensions(if any) of all patents or patent applications withinthe Licensed Patents in the Territory. The filing, prosecution and maintenance of patentsand patent applications pursuant to this Section 6.2 shall be done through patent counselselected by Protherics and reasonably acceptable to Glenveigh. Protherics will keepGlenveigh informed of all significant patent matters relating to the Licensed Patents, andwill give Glenveigh a reasonable opportunity to review and provide input on the prosecutionof applications within the Licensed Patents. Protherics shall have the right, after consultation with Glenveigh, and upon no less than thirty (30) days’notice, to abandon any of the patents or patent applications within the Licensed Patents inthe Territory, In the event that Protherics decides to abandon any patent and/or patentapplication within the Licensed Patents in the Territory, Glenveigh shall have the right tocontinue the filing, prosecution or maintenance of any such patent or patent applicationthat Protherics wishes to abandon, at Glenveigh’s sole cost and expense.     2. Additional Representations, Warranties and Covenants of Glenveigh. Each of theGlenveigh Holders hereby represents and warrants, severally and not jointly, to Protherics, that:          2.1. Authorization. Each Glenveigh Holder has full power and authority to enter intothis Amendment. This Amendment constitutes the valid and legally binding obligation of eachGlenveigh Holder, enforceable in accordance with its terms.
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          2.2. Purchase Entirely for Own Account. This Amendment is made with Glenveigh Holder in reliance upon Glenveigh Holder’s representation to Protherics, which by GlenveighHolder’s execution of this Amendment, Glenveigh Holder hereby confirms, that the Additional PTIOrdinary Shares to be acquired by Glenveigh will be acquired for investment for Glenveigh’s ownaccount, not as a nominee or agent, and not with a view to the resale or distribution in United States of anypart thereof, and that except for distributions by, to and among the Glenveigh Holders and their respectivemembers, Glenveigh Holder has no present intention of selling, granting any participation in, orotherwise distributing the same. By executing this Amendment, Glenveigh Holder further represents thatGlenveigh Holder does not presently have any contract, undertaking, agreement or arrangement with anyperson (other than as among the Glenveigh Holders and their respective members) to sell, transfer orgrant participations to such person or to any third person, with respect to any of the AdditionalPTI Ordinary Shares. Glenveigh Holder has not been formed for the specific purpose of acquiring theAdditional PTI Ordinary Shares.          2.3.Disclosure of Information. Each Glenveigh Holder has received and reviewed the Disclosure Statement dated April 11, 2008 provided by Protherics and has the opportunityto ask questions and receive answers from Protherics’s management about Protherics’s business,management, financial affairs and the terms and conditions of the Additional PTI Ordinary Shares.          2.4. No Registration of Additional PTI Ordinary Shares. Each Glenveigh Holderacknowledges that the Additional PTI Ordinary Shares issued pursuant to Section 5.2 (i) have notbeen registered under the United States Securities Act of 1933, as amended (the **“Securities Act”)**or the securities laws of any state of the United States **(“State Securities Laws”),**and will beissued to Glenveigh in a transaction not requiring registration under the Securities Act or anyState Securities Laws, and may not be offered, sold or otherwise transferred except in compliancewith the registration requirements of the Securities Act or any applicable State Securities Law,pursuant to an exemption therefrom or in a transaction not subject thereto. Each certificaterepresenting Additional PTI Ordinary Shares will contain a legend substantially to the followingeffect:     **THE SECURITIES EVIDENCED HEREBY HAVE NOT BEEN AND WILL NOT BE REGISTERED UNDER THEUNITED STATES SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”), OR ANY STATESECURITIES LAWS. NEITHER THIS SECURITY NOR ANY INTEREST OR PARTICIPATION HEREIN MAY BEREOFFERED, SOLD, ASSIGNED, TRANSFERRED, PLEDGED, ENCUMBERED OR OTHERWISE DISPOSED OF IN THEUNITED STATES OR TO OR FOR THE ACCOUNT OF A U.S. PERSON IN THE ABSENCE OF SUCH REGISTRATIONOR UNLESS THE TRANSACTION IS EXEMPT FROM, OR NOT SUBJECT TO, THE REGISTRATION REQUIREMENTSOF THE SECURITIES ACT.**     Neither Protherics nor Protherics plc is under an obligation to register the sale, transferor other disposition of the Additional PTI Ordinary Shares by Glenveigh or on behalf of Glenveighunder the Securities Act, or to take any other action necessary in order to make compliance withan exemption from such registration available.          2.5.Accredited Investor. Each Glenveigh Holder is an accredited investor as defined in Rule 501(a) of Regulation D promulgated under the Securities Act.          2.6. No General Solicitation. No Glenveigh Holder, nor any of its officers, directors, employees, agents, stockholders or partners has either directly or indirectly, includingthrough a broker or finder (a) engaged in any general solicitation, or (b) published any advertisement inconnection with the offer and sale of the Additional PTI Ordinary Shares.
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     2.7. Exculpation Among Glenveigh Holder. Each Glenveigh Holder acknowledges that it is not relying upon any person, firm or corporation, other than Protherics and itsofficers and directors, in making its investment or decision to invest in Protherics. Each Glenveigh Holderagrees that no Glenveigh Holder nor the respective controlling persons, officers, directors, partners,agents, or employees of any Glenveigh Holder shall be liable to any other Glenveigh Holder for any actionheretofore or hereafter taken or omitted to be taken by any of them in connection with thepurchase of the Additional PTI Ordinary Shares.     2.8. Residence. If Glenveigh Holder is an individual, then Glenveigh Holder resides in the state or province identified in the address of Glenveigh Holder set forth in thepreamble of the License Agreement; if Glenveigh Holder is a partnership, corporation, limited liabilitycompany or other entity, then the office or offices of Glenveigh Holder in which its principal place ofbusiness is located is at the address or addresses of Glenveigh Holder set forth in the preamble of the LicenseAgreement.     3. Protherics Representations, Warranties and Covenants. Protherics represents,warrants and covenants to Glenveigh as follows:          3.1. Authorization. Protherics has full power and authority to enter into thisAmendment. This Amendment constitutes the valid and legally binding obligation of Protherics,enforceable in accordance with its terms.          3.2 PTI Ordinary Shares and Additional PTI Ordinary Shares. Following the AmendmentEffective Date, the PTI Ordinary Shares issued to Glenveigh pursuant to Section 5.1.2 and anyAdditional PTI Ordinary Shares that may be issued to Glenveigh pursuant to Section 5.2 will befreely transferable under the rules of the London Stock Exchange, the Listing Rules of the UKFinancial Services Authority and English law, subject only to the restrictions contained inSection 2.4 of this Amendment and as referred to in Article 202 of the Articles of Association ofProtherics pls. Subject to applicable law, Protherics agrees and covenants to cooperate fully withGlenveigh and Protherics’ transfer agent (including removing of any legends as appropriate) in anyfuture sales by Glenveigh of the PTI Ordinary Shares and any Additional PTI Ordinary Shares thatare lawfully made under applicable securities laws and exemptions, including but not limited to,Regulation S promulgated under the Securities Act.     4. Amendment and Ratification. The License Agreement is hereby amended in accordancewith the foregoing provisions of this Amendment. The License Agreement, as amended asprovided herein, is hereby ratified and shall remain in full force and effect.     5. Defined Terms. Capitalized terms used in this Amendment shall have the samemeanings as in the License Agreement unless otherwise defined herein.     6. Counterparts. This Amendment may be executed in counterparts by original orfacsimile signature, each of which shall be deemed an original, but all of which together shallconstitute one and the same instrument.**[SIGNATURES ON FOLLOWING PAGE]**
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     IN WITNESS WHEREOF, the Parties hereto have caused this Amendment to be executed by their dulyauthorized representative as of the date first above written.           **GLENVEIGH PHARMACEUTICALS, LLC** **PROTHERICS MEDICINESDEVELOPMENT LIMITED**             By: /s/ C. David Adair, M.D.    By: /s/ Saul Komisar     Name: C. David Adair, M.D.      Name: Saul Komisar    Title:   Chairman     Title: President/ Director       **GLENVEIGH RESEARCH, LLC**