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                                                                    EXHIBIT 4.28

                LETTER OF APPOINTMENT OF A NON-EXECUTIVE DIRECTOR




September 6th 2004



Professor Anthony Atkinson
Kingston Lodge
Canada Road
West Wellow
Hampshire
SO51 6DE



Dear Tony


               PROTHERICS PLC (THE "COMPANY") AND YOUR APPOINTMENT
                    TO THE BOARD AS A NON-EXECUTIVE DIRECTOR

Following the recommendation of the nomination committee, the board of the
Company (the "BOARD") is pleased to hear that you have accepted our offer to
join on the Board as a non-executive director with effect from 22 April 2004.
This letter confirms the main terms of your appointment to this office. Your
appointment was ratified by the Company's shareholders at the annual general
meeting on 22 July 2004 and is subject to the Company's articles of association
as amended from time to time. If there is a conflict between the terms of this
letter and the articles of association then the articles shall prevail. It is
agreed that this is a contract for services not a contract of employment.

DUTIES

1.       You have already been informed how the Board is structured and what
         authorities are delegated to the Chief Executive and his colleagues.

2.       The Board as a whole is collectively responsible for promoting the
         success of the Company by directing and supervising the Company's
         affairs. The Board's role is to:

         (a)      provide entrepreneurial leadership to the Company within a
                  framework of prudent and effective controls which enable risk
                  to be assessed and managed;

         (b)      set the Company's strategic aims, ensure that the necessary
                  financial and human resources are in place for the Company to
                  meet its objectives, and review management performance; and

         (c)      set the Company's values and standards and ensure that its
                  obligations to its shareholders and others are understood and
                  met.

3.       In your role as a non-executive director you are required (with the
         other non-executives) to:

         (a)      constructively challenge and contribute to the development of
                  strategy;

         (b)      scrutinise the performance of management in meeting agreed
                  goals and objectives and monitor the reporting of performance;


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         (c)      satisfy yourself that financial information is accurate and
                  that financial controls and systems of risk management are
                  robust and defensible;

         (d)      be responsible for determining appropriate levels of
                  remuneration of executive directors and have a prime role in
                  appointing, and where necessary removing, senior management
                  and in succession planning.

4.       You will be required to:

         (a)      exercise relevant powers under the Company's memorandum and
                  articles of association;

         (b)      perform your duties faithfully, efficiently and diligently and
                  use all reasonable endeavours to promote the interests and
                  reputation of the Company;

         (c)      comply with your fiduciary duties;

         (d)      report the wrongdoing (including acts of misconduct,
                  dishonesty, breaches of contract, fiduciary duty, company
                  rules or the rules of the relevant regulatory bodies) whether
                  committed, contemplated or discussed by any other director or
                  member of staff of the Company and any group company of which
                  you were aware to the Board immediately ,irrespective of
                  whether this may involve some degree of self incrimination;

         (e)      At the request of the Chairman, serve on the nomination and
                  remuneration committees of the Board and attend wherever
                  possible all meetings of the committees.

         (f)      attend wherever possible all general meetings of the Company;

         (g)      attend wherever possible all meetings of the Board, which
                  meets about 8 times a year, normally at the Company's offices
                  at Ludgate Hill, London;

         (h)      consider all relevant papers in advance of each meeting in
                  order to ensure that you can play a full part in the work of
                  the Board and its committees;

         (i)      bring independent judgement to bear on issues of strategy,
                  policy, resources, performance and standards of conduct;

         (j)      make yourself available (on reasonable notice) to provide ad
                  hoc advice to individual directors of the Company;

         (k)      provide guidance and direction in planning, developing and
                  enhancing the future strategic direction of the Company;

         (l)      share responsibility with the other directors for the
                  effective control of the Company and with the other
                  non-executive directors for the supervision of the executive
                  directors; and

         (m)      comply with the Financial Services Authority's Model Code for
                  securities transactions by directors of listed companies and
                  with any code of conduct relating to securities transactions
                  by directors and specified employees issued by the Company
                  from time to time.


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5.       Overall the Company anticipates that you will need to spend one day per
         month fulfilling your duties. This will include the board meetings,
         annual general meetings, one board away-day each year and at least one
         site visit per year. In addition you will be expected to spend an
         appropriate period of time preparing for each meeting. By accepting
         this appointment you confirm that you are able to commit sufficient
         time to the role to meet the Company's expectations.

6.       The Company seeks to adhere to the principles in the Cadbury Report on
         Corporate Governance, the Greenbury Report on Directors' Remuneration,
         the Hampel Report on Corporate Governance and the Turnbull Report on
         Internal Control. You will be expected to carry out your duties in
         accordance with the principles set out in these reports.

7.       The performance of the Board and its committees, and of individual
         directors, is evaluated annually.

8.       You shall, in pursuance of your duties hereunder, be entitled to
         request such information from the Company, its subsidiary undertakings
         (as defined in section 258 of the Companies Act 1985 as amended from
         time to time) or its or their employees, consultants or professional
         advisers as may be reasonably necessary to enable you to perform your
         role effectively. The Company shall use its reasonable endeavours to
         provide such information promptly.

CONFIDENTIALITY

During the course of your duties you will have access to confidential
information belonging to the Company and its subsidiary undertakings (including,
but not limited to, details of suppliers, customers, margins, know-how,
marketing and other relevant business information). Unauthorised disclosure of
this information could seriously damage the Company. You therefore undertake not
to use or disclose such information save in pursuance of your duties or in
accordance with any statutory obligation or court or similar order.

Your attention is drawn to the rules relating to the disclosure of price
sensitive information. You must not make any statement or do anything which may
be a breach of these rules without prior clearance from the Chairman or Company
Secretary.

OUTSIDE INTERESTS

The agreement of the chairman should be sought before you accept any new outside
interests which might affect the time you are able to devote to this
appointment.

In accordance with the principles set out in the Combined Code you must inform
the Board Chairman of any interests which you have, or acquire, which might
reasonably be thought to jeopardise your independence from the Company.

During your appointment you must not take up any office or employment with, or
have any interest in, any firm or company which is or may be in direct or
indirect competition with the Company.

INSURANCE

During your appointment you will be covered by the Company's directors' and
officers' liability insurance on the terms in place from time to time. The
current indemnity limit is Pound Sterling10,000,000. A copy of the policy
document is available from Barry Riley. The Company does not guarantee to
maintain this insurance cover after the termination of your appointment, but you
will continue to be covered by the policy or any replacement on the same basis
as the rest of the Board.






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APPOINTMENT

Your appointment is deemed to have commenced on 22 April 2004 and is terminable
by three months' notice from either the Company or yourself. It is envisaged
that your appointment will initially be for a term of 3 years. The continuation
of your appointment depends upon satisfactory performance and re-election at
forthcoming Annual General Meetings.

Not withstanding the aforementioned notice provisions, the Company may terminate
your appointment with immediate effect if you have:

(a)      committed any serious breach or (after warning in writing) any repeated
         or continued material breach of your obligations to the Company (which
         include an obligation not to breach your fiduciary duties);

(b)      been guilty of any act of dishonesty or serious misconduct or any
         conduct which (in the reasonable opinion of the Board) tends to bring
         you or the Company into disrepute; or

(c)      been declared bankrupt or have made an arrangement or composition with
         of for the benefit of your creditors,

or for any other reason set out in the Company's articles of association.

All appointments and reappointments to the Board are, of course, subject to the
Company's articles of association. If you are not re-elected to your position as
a director of the Company by the shareholders at any time and for any reason
then this appointment shall terminate automatically and with immediate effect.

On termination of the appointment you shall only be entitled to such fees as may
have accrued to the date of termination together with reimbursement in the
normal way of any expenses properly incurred prior to that date.

REMUNERATION

The fee is Pound Sterling 21,000 per annum (subject to income tax and statutory
deductions) and is payable monthly in arrears. It may be subject to upward
review at the discretion of the Company after one year. If you undertake any
special duties beyond those specified in this letter you will not receive any
additional payment unless agreed with the Board in advance.

EXPENSES

The Company will reimburse you for any expenses that you may incur properly and
reasonably in performing your duties and which are properly documented. Such
expenses would include reasonable legal fees if circumstances should arise in
which it was necessary for you to seek separate legal advice about the
performance of your duties. In such a situation, you are required to discuss the
issue either with me or with one of your non-executive colleagues in advance.

INDEPENDENT PROFESSIONAL ADVICE

In some circumstances you may think that you need professional advice in the
furtherance of your duties as a director. It may also be appropriate for you to
seek advice from independent advisers at the Company's expense. Before you
obtain such independent advice you must inform the Board Chairman that such
advice is to be sought. The Company will reimburse the full cost of any
reasonable expenditure incurred in accordance with you seeking such advice.


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DATA PROTECTION

By signing this agreement you consent to the Company holding and processing
information about you which you may provide or which it may acquire during the
course of this agreement, providing such use is in accordance with the Data
Protection Act 1998. In particular you consent to the Company holding and
processing:

(a)      personal data relating to you, for administrative and management
         purposes; and

(b)      "sensitive personal data" relating to you (as defined in the Data
         Protection Act 1998) including, for example:

                  (i)      your health records and any medical reports given to
                           or obtained by the Company, for monitoring sick leave
                           and taking decisions as to your fitness to work;

                  (ii)     your racial or ethnic origin (in order to monitor
                           compliance with the Race Relations Act 1976);

                  (iii)    any information relating to criminal proceedings in
                           which you have been involved for compliance with the
                           Company's legal or regulatory requirements, for
                           insurance purposes, and in relation to its
                           obligations to third parties.

You also consent to the Company making such information available to:

(a)      its group companies, offices and (if necessary) customers outside the
         European Economic Area in order to further its business interests; and

(b)      its group companies, its offices, those who provide products or
         services to the Company, regulatory authorities, governmental or quasi
         governmental organisations and potential purchasers of the Company or
         its business.

THIRD PARTY RIGHTS

The Contracts (Rights of Third Parties) Act 1999 shall not apply to this
agreement. No person other than the parties to this agreement and any group
company shall have any rights under it and it will not be enforceable by any
person other than those parties.

Please sign and return the enclosed copy of this letter to confirm your
agreement to the above terms.

The Company looks forward to working with you in the future.

Yours sincerely


/s/ Andrew Heath

ANDREW HEATH
for and on behalf of Protherics Plc



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I, Professor Anthony Atkinson, agree to the above terms of appointment as a
non-executive director of Protherics Plc.

Name /s/ A. Atkinson
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Date 9 September 2004
    ---------------------------

In the presence of: /s/ N. Blissett

Witness signature: Natasya Blissett

Witness name: Natasya Blissett

Witness address: 8 Kelsey Road, Salisbury SA1 1JP

Witness occupation: P/A