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                                                                    EXHIBIT 11.1


                                 PROTHERICS PLC

                                 CODE OF ETHICS


         This Code of Ethics sets out basic principles and standards of conduct
to guide the Chief Executive Officer, Chief Financial Officer and Controller
(each an "Officer" and collectively, the "Officers") of Protherics PLC (the
"Company"). Each of the Officers must conduct themselves in accordance with
these principles and standards.

         Claims of violations of this Code will be investigated by appropriate
personnel or Company representatives. Those who violate the standards in this
Code may be subject to disciplinary action, including dismissal.

1.       HONEST AND ETHICAL CONDUCT

         The Officers should act ethically and in good faith, with honesty and
integrity, when acting on behalf of the Company or in connection with the
Company's business or operations.

2.       COMPLIANCE WITH LAWS, RULES AND REGULATIONS

         Obeying the law, both in letter and in spirit, is the foundation on
which this Company's ethical standards are built. All of the Officers must
respect and obey the laws of the cities, states and countries in which we
operate.

         The Officers will receive from time to time training sessions to
promote compliance with laws, rules and regulations.

3.       RECORD-KEEPING

         Accuracy and reliability in the preparation of all business records is
mandated by law and is critically important to the Company's decision-making
process and to the proper discharge of its financial, legal, and reporting
obligations. All of the Company's books, records, accounts and financial
statements must be maintained in reasonable detail, must appropriately reflect
the Company's transactions and must conform both to applicable legal
requirements and to the Company's system of internal controls. Unrecorded or
"off-balance sheet" liabilities or assets should not be maintained unless
permitted by applicable law or regulation. The Officers have a responsibility to
promote full, fair, accurate, timely and understandable disclosure in the
reports and documents that the Company provides to its shareholders or files
with or submits to the U.K. Stock Exchange and U.S. Securities and Exchange
Commission.

4.       CONFLICTS OF INTEREST

         The Officers must avoid conflicts of interest involving the Company or
its business. A "conflict of interest" occurs when an Officer's private interest
interferes in any way, or even appears to interfere, with the interests of the
Company as a whole. A conflict situation can arise when an Officer takes actions
or has interests that may make it difficult to perform his or her work for the
Company objectively and effectively. Conflicts of interest also arise when an



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Officer or a member of his or her family, receives improper personal benefits as
a result of his or her position in or with the Company. Loans to, or guarantees
of obligations of, such persons are of special concern and may be prohibited by
law. Any Officer who becomes aware of a conflict or potential conflict of
interest or any material transaction or relationship that reasonably could be
expected to give rise to a conflict of interest should bring it to the attention
of the General Counsel. Conflicts of interest may not always be clear, so if you
have a question, you should consult with the General Counsel of the Company or
other personnel or legal counsel designated by the Company from time to time.

5.       CONFIDENTIALITY

         The Officers must maintain the confidentiality of information entrusted
or made available to them by the Company or the Company's affiliated entities,
except when disclosure is authorised by the Company or legally mandated, and
must not use that information for personal advantage. Confidential information
includes all financial, patient and other records and non-public information
that, if disclosed, might be of use to competitors, or harmful to the Company or
its affiliated practices.

6.       CORPORATE OPPORTUNITIES

         The Officers are prohibited from (a) taking for themselves
opportunities that are discovered through the use of the Company's property,
information or position, without the consent of a majority of the disinterested
members of the Board of Directors, (b) using the Company's property, information
or position for improper personal gain or (c) competing with the Company
directly or indirectly. Employees, officers and directors owe a duty to the
Company to advance its legitimate interests when the opportunity to do so
arises.

7.       FAIR DEALING

         Each Officer should endeavor to deal fairly with the Company's
affiliated entities, suppliers, competitors and employees. The Officers should
not take unfair advantage of anyone through manipulation, concealment, abuse of
privileged information, misrepresentation of material facts or any other
unfair-dealing practice in connection with the Company's business.

8.       PROTECTION AND PROPER USE OF COMPANY ASSETS

         The Officers should protect the Company's assets and ensure their
efficient use. Theft, carelessness and waste have a direct impact on the
Company's profitability. All Company assets should be used for legitimate
business purposes.

9.       WAIVERS OF THE CODE OF ETHICS

         Any waiver of this Code for the Officers may be made only by the
Company's non-executive Chairman who may refer the matter to the Company's Board
of Directors and will be promptly disclosed as required by law or other
applicable rules.


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10.      REPORTING ILLEGAL OR UNETHICAL BEHAVIOR OR VIOLATIONS OF THIS CODE

         We must all work to ensure prompt and consistent action against
violations of this Code. Officers are encouraged to contact the Company's
Chairman or other appropriate personnel about observed illegal or unethical
behavior or violations of this Code and when in doubt about the best course of
action in a particular situation. Any claim of a possible violation may be made
anonymously if the claimant so desires, and all claimants shall be provided
confidentiality in the handling of the potential violation. The Officers are
expected to cooperate in internal investigations of misconduct.

11.      ADMINISTRATION OF CODE

         This Code shall be administered by the Company's Chairman. The Officers
are encouraged to seek guidance regarding the application or interpretation of
this Code from the Company's Chairman and are expected to cooperate fully in any
investigation of any potential violation of this Code.













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