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[MITOKOR LETTERHEAD]                                               Exhibit 10.12


March 15, 2001


Mr. Ron Deane
5205 Fiore Terrace #B-214
San Diego, CA 92122


Dear Ron,

I am very pleased that you have accepted our offer to join MitoKor on a
regular, full time basis in the position of Chief Business Officer reporting
directly to me. Your contributions as an advisor to MitoKor over the past
several months have been very beneficial and I look forward to working with
you in this new capacity.

This letter will outline your employment arrangement with MitoKor for the
next nine to twelve months. At the end of that period, we will mutually
determine whether an extension of your time with MitoKor is appropriate. Your
hire date will be March 1, 2001. Further details of this offer are as follows:

Base Salary:          You will be paid an annualized rate of $175,000 USD, in
                      accordance with MitoKor's standard payroll cycle, which is
                      currently semi-monthly.

Performance Bonus:    In addition to your base salary, you will be eligible to
                      participate in the discretionary MitoKor Executive Bonus
                      Plan. Under this plan you will be eligible for a cash
                      bonus of up to 30% of your base salary, based upon the
                      achievement of corporate and individual milestones. This
                      bonus is typically calculated and paid after the end of
                      each calendar year and is subject to the approval of
                      MitoKor's Board of Directors.

Stock Options:        You have recently been granted an additional 20,000
                      MitoKor stock options in anticipation of your acceptance
                      of this offer of employment. This new grant gives you a
                      total of 40,000 stock options. These stock option grants
                      have been approved by the MitoKor Board of Directors and
                      are subject to the vesting schedule and terms and
                      conditions outlined in the MitoKor Employee Stock Option
                      Plan ("the Plan"). You will be asked to sign a formal
                      grant letter, which will be issued to you shortly.




Mr. Ron Deane
March 15, 2001
Page 2


Benefits:             As an employee of MitoKor you will be eligible for
                      comprehensive health insurance benefits for yourself and
                      your eligible dependents, effective on April 1, 2001. In
                      addition, you will be eligible for other basic group
                      benefits effective on your hire date. These basic benefits
                      include dental insurance and vision care insurance. You
                      will also be eligible for term life insurance and
                      long-term and short-term disability insurance, effective
                      on your hire date.

                      You will not be charged for your insurance coverage,
                      however, if you choose to cover your dependents, you will
                      be asked to contribute a portion of the cost of their
                      coverage. The cost of dependent coverage will vary based
                      upon the number of dependents covered and plan selection.
                      Any premiums you pay, however, will be paid pre-tax. Full
                      details of group benefits will be provided once you are on
                      board.

                      Additional benefits for which you will be eligible
                      include: accrued Paid Time Off equal to twenty days per
                      year; ten paid holidays per calendar year; and
                      participation in the MitoKor Flexible Spending Plan which
                      allows you to defer some of your earnings pre-tax, into a
                      spending account to be used for payment of non-reimbursed
                      medical and/or child care expenses.

Travel to Australia:  I anticipate that you will occasionally travel to
                      Australia on MitoKor or Mimotopes business. As always,
                      the Company will pay your business travel expenses. I
                      also anticipate that Marcia will travel to Australia on
                      occasion. If this is the case, MitoKor will provide Marcia
                      with one coach class, round trip ticket per quarter. At
                      the end of your assignment with MitoKor, both you and
                      Marcia will be provided airline tickets for your return
                      trip to Australia. Reservations for all travel should be
                      made as far in advance as possible in order to obtain the
                      best airfare.

Housing and
Relocation:           MitoKor will continue to pay the rent on your current
                      apartment until April 30, 2001. In order to avoid the
                      disruption caused by moving to another location, you will
                      remain in the same apartment, however, as of May 1, 2001
                      you will be responsible for payment of rent in the amount
                      of $2,250.00 per month. This payment will be made directly
                      to MitoKor on the first day of each month and will
                      continue through the earlier of your return to Australia
                      or February 28, 2002. In addition although your apartment
                      is fully furnished, there may be some personal items that
                      you would like to have moved from Australia. MitoKor will
                      cover the expenses incurred in


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Mr. Ron Deane
March 15, 2001
Page 3


                      such a move both to the United States, and back to
                      Australia at the end of your assignment. In order to
                      assist you in this transition to the San Diego area,
                      MitoKor will provide assistance through a company called
                      Relocation Coordinates.

                      Through Relocation Coordinates, your assigned relocation
                      counselor will provide you and Marcia with an orientation
                      to the San Diego area, assistance in searching for an
                      apartment, and assistance in obtaining a social security
                      card and driver's license. They will also coordinate the
                      move of your personal items from Australia to San Diego.

Automobile:           MitoKor will continue to make lease payments on the
                      automobile you are currently driving through April 30,
                      2001. As of May 1, 2001, you will be responsible for
                      payment of all automobile expenses.


MitoKor is an at-will employer and as such your employment must be entered
into voluntarily and for no specified period. As a result, you are free to
resign or the company may terminate your employment at any time, for any
reason, with or without cause. No one other than the CEO has the authority to
alter this employment relationship, either verbally or in writing and the CEO
can only alter this relationship in writing, signed by you and the CEO.

As an employee of MitoKor, you will be required to sign MitoKor's Employee
Agreement Regarding Confidentiality and Inventions ("Agreement"). If you
accept this offer, the terms described in this letter and in the
aforementioned Agreement shall be the terms of your employment, provided,
however, that your duties are performed in accordance with all standards and
policies adopted by the company. Your duties may change from time to time
upon reasonable notice, depending upon the needs of the company and your
skills. This letter supersedes any prior agreements, representations or
promises of any kind, express or implied, concerning your employment and it
constitutes the full and complete agreement between you and the Company.

Ron, we are very pleased to have you on the MitoKor team. We are confident
that you have much to contribute to the success of MitoKor. The strength of
our technology, the quality and experience of our personnel and your presence
will facilitate this success.


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Mr. Ron Deane
March 15, 2001
Page 4



If the terms described herein are acceptable to you, please acknowledge your
acceptance by signing below on both copies and return one original to me.
Please keep one copy for your records.


Sincerely,

/s/ Walter H. Moos

Walter H. Moos, Ph.D.
Chairman and CEO



Accepted:

/s/ Ron Deane                                  03/15/01
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Ron Deane                             Date