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                                                                   Exhibit 10.16

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                AMENDED AND RESTATED LOAN AND SECURITY AGREEMENT
                                     MITOKOR

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                                TABLE OF CONTENTS

                                                                            Page
                                                                            ----

1    ACCOUNTING AND OTHER TERMS................................................4

2    LOAN AND TERMS OF PAYMENT.................................................4
     2.1   Promise to Pay......................................................4
     2.2   Termination of Commitment to Lend...................................5
     2.3   Interest Rate, Payments.............................................5
     2.4   Fees................................................................6
     2.5   Additional Costs....................................................6

3    CONDITIONS OF LOANS.......................................................6
     3.1   Conditions Precedent to Initial Credit Extension....................6
     3.2   Conditions Precedent to all Credit Extensions.......................6

4    CREATION OF SECURITY INTEREST.............................................6
     4.1   Grant of Security Interest..........................................6
     4.2   Certificate of Deposit Collateral...................................6
     4.3   Concerning Revised Article 9 of the Uniform Commercial Code.........6

5    REPRESENTATIONS AND WARRANTIES............................................7
     5.1   Due Organization and Authorization..................................7
     5.2   Collateral..........................................................7
     5.3   Litigation..........................................................7
     5.4   No Material Adverse Change in Financial Statements..................7
     5.5   Solvency............................................................7
     5.6   Regulatory Compliance...............................................7
     5.7   Subsidiaries........................................................8
     5.8   Full Disclosure.....................................................8

6    AFFIRMATIVE COVENANTS.....................................................8
     6.1   Government Compliance...............................................8
     6.2   Financial Statements, Reports, Certificates.........................8
     6.3   Inventory; Returns..................................................9
     6.4   Taxes...............................................................9
     6.5   Insurance...........................................................9
     6.6   Primary Accounts and Balances.......................................9
     6.7   Financial Covenants.................................................9
     6.8   Further Assurances..................................................9
     6.9   Right To Invest....................................................10

7    NEGATIVE COVENANTS.......................................................10
     7.1   Dispositions.......................................................10
     7.2   Changes in Business, Ownership, Management or Business Locations...10
     7.3   Mergers or Acquisitions............................................10
     7.4   Indebtedness.......................................................10
     7.5   Encumbrance........................................................10
     7.6   Distributions; Investments.........................................11
     7.7   Transactions with Affiliates.......................................11
     7.8   Subordinated Debt..................................................11
     7.9   Compliance.........................................................11

8    EVENTS OF DEFAULT........................................................11


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     8.1   Payment Default....................................................11
     8.2   Covenant Default...................................................11
     8.3   Material Adverse Change............................................11
     8.4   Attachment.........................................................12
     8.5   Insolvency.........................................................12
     8.6   Other Agreements...................................................12
     8.7   Judgments..........................................................12
     8.8   Misrepresentations.................................................12

9    BANK'S RIGHTS AND REMEDIES...............................................12
     9.1   Rights and Remedies................................................12
     9.2   Power of Attorney..................................................13
     9.3   Bank Expenses......................................................13
     9.4   Bank's Liability for Collateral....................................13
     9.5   Remedies Cumulative................................................13
     9.6   Demand Waiver......................................................13

10   NOTICES..................................................................13

11   CHOICE OF LAW, VENUE AND JURY TRIAL WAIVER...............................14

12   GENERAL PROVISIONS.......................................................14
     12.1  Successors and Assigns.............................................14
     12.2  Indemnification....................................................14
     12.3  Time of Essence....................................................14
     12.4  Severability of Provision..........................................14
     12.5  Amendments in Writing, Integration.................................14
     12.6  Counterparts.......................................................15
     12.7  Survival...........................................................15
     12.8  Confidentiality....................................................15
     12.9  Effect of Amendment and Restatement................................15
     12.10 Attorneys' Fees, Costs and Expenses................................15

13   DEFINITIONS..............................................................15
     13.1  Definitions........................................................15


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         THIS AMENDED AND RESTATED LOAN AND SECURITY AGREEMENT dated June 21,
2001, between SILICON VALLEY BANK ("Bank"), whose address is 3003 Tasman Drive,
Santa Clara, California 95054 with a loan production office located at 9645
Scranton Road, Suite 110, San Diego, California 92121 and MITOKOR ("Borrower"),
whose address is 11494 Sorrento Valley Road, San Diego, California 92121.

                                    RECITALS

         A.  Bank and Borrower are parties to that certain Loan and Security
Agreement dated March 23, 1998, as amended (collectively, the "Original
Agreement").

         B.  Borrower and Bank desire in this Agreement to set forth their
agreement with respect to a equipment line and term loan and to amend and
restate in its entirety without novation the Original Agreement in accordance
with the provisions herein.

                                    AGREEMENT

         The parties agree as follows:

1        ACCOUNTING AND OTHER TERMS

         Accounting terms not defined in this Agreement will be construed
following GAAP. Calculations and determinations must be made following GAAP. The
term "financial statements" includes the notes and schedules. The terms
"including" and "includes" always mean "including (or includes) without
limitation," in this or any Loan Document.


2        LOAN AND TERMS OF PAYMENT

2.1      PROMISE TO PAY.

         Borrower promises to pay Bank the unpaid principal amount of all Credit
Extensions and interest on the unpaid principal amount of the Credit Extensions.


2.1.1    EQUIPMENT ADVANCES.

         (a) Through December 31, 2001 (the "Equipment Availability End Date"),
Bank will make advances ("Equipment Advance" and, collectively, "Equipment
Advances") not exceeding the Committed Equipment Line. The Equipment Advances
may only be used to finance or refinance Equipment purchased on or after 90 days
before the date of each Equipment Advance (except for the initial Equipment
Advance which shall allow for Eligible Equipment purchased on or after 120 days
and can be financed at cost) and may not exceed 100% of the equipment invoice
excluding taxes, shipping, warranty charges, freight discounts and installation
expense. Software licenses, leasehold improvements, and other soft costs may
constitute up to $500,000, furniture up to $200,000, of the aggregate Equipment
Advances. Each Equipment Advance must be for a minimum of $50,000. The number of
Equipment Advances is limited to once per month.

         (b) Interest accrues from the date of each Equipment Advance at the
rate in Section 2.3(a) and is payable monthly until the Equipment Availability
End Date occurs. Equipment Advances outstanding on the Equipment Availability
End Date are payable in 36 equal monthly installments of principal, plus accrued
interest, beginning on the last day of each month following the Equipment
Availability End Date and ending on December 31, 2004 (the "Equipment Maturity
Date"). Equipment Advances when repaid may not be reborrowed.

         (c) To obtain an Equipment Advance, Borrower must notify Bank (the
notice is irrevocable) by facsimile no later than 12:00 p.m. Pacific time 1
Business Day before the day on which the Equipment


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Advance is to be made. The notice in the form of Exhibit B (Payment/Advance
Form) must be signed by a Responsible Officer or designee and include a copy of
the invoice for the Equipment being financed.

2.2      TERMINATION OF COMMITMENT TO LEND.

         Bank's obligation to lend the undisbursed portion of the Obligations
will terminate if, in Bank's sole discretion, there has been a material adverse
change in the general affairs, management, results of operation, condition
(financial or otherwise) or the prospect of repayment of the Obligations, or
there has been any material adverse deviation by Borrower from the most recent
business plan of Borrower presented to and accepted by Bank prior to the
execution of this Agreement.

2.2.1    TERM LOAN 1.

         (a) Borrower will continue to pay the outstanding amount under the Term
Loan 1 as follows:

         (b) Borrower will continue to pay 11 equal installments of principal of
$27,777.78 plus interest (the "Term Loan 1 Payment"). Each Term Loan 1 Payment
is payable on the last day of each month during the term of the loan. Borrower's
final Term Loan 1 Payment, due on April 30, 2002, includes all outstanding Term
Loan 1 principal and accrued interest.

2.2.2    TERM LOAN 2.

         (a) Borrower will continue to pay the outstanding amount under the Term
Loan 2 as follows:

         (b) Borrower will continue to pay 25 equal installments of principal of
$55,555.55 plus Interest (the "Term Loan 2 Payment"). Each Term Loan 2 Payment
is payable on the last day of each month during the term of the loan. Borrower's
final Term Loan 2 Payment, due on June 15, 2003, includes all outstanding Term
Loan 2 principal and accrued interest.

2.3      INTEREST RATE, PAYMENTS.

         (a) Interest Rate. (i) Prior to the Equipment Availability End Date
Equipment Advances accrue interest on the outstanding principal balance at a per
annum rate of 1 percentage point above the Prime Rate. Beginning on the
Equipment Availability End Date and thereafter, Borrower may elect either the
variable interest rate as provided above, provided, such rate shall not be less
than 8%, or a fixed rate, equal to the Treasury Yield Percentage plus 375 basis
points, provided such rate shall not be less than 7.75%. Any prepayment of the
Committed Equipment Line must include a pre payment fee equal to the Make Whole
Premium; (ii) the outstanding balance of the Term Loan 2 accrues interest at a
fixed per annum rate of 9.47 percent. Any prepayment of the Term Loan 2 must
include a Prepayment Fee; and (iii) the outstanding balance of the Term Loan 1
accrues interest at a per annum rate equal to the Prime Rate. After the
occurrence and during the continuance of an Event of Default, Obligations accrue
interest at 5 percent above the rate effective immediately before the Event of
Default. The interest rate increases or decreases when the Prime Rate changes.
Interest is computed on a 360 day year for the actual number of days elapsed.

         (b) Payments. Interest due on the Equipment Advances is payable on the
last day of each month. Bank may debit any of Borrower's deposit accounts
including Account Number 3300047794 for principal and interest payments owing or
any amounts Borrower owes Bank. Bank will promptly notify Borrower when it
debits Borrower's accounts. These debits are not a set-off. Payments received
after 12:00 noon Pacific time are considered received at the opening of business
on the next Business Day. When a payment is due on a day that is not a Business
Day, the payment is due the next Business Day and additional fees or interest
accrue.


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2.4      FEES.

         Bank Expenses. Borrower will pay all Bank Expenses (including
reasonable attorneys' fees and reasonable expenses not to exceed $2,500 for
documentation and negotiation of this Agreement) incurred through and after the
date of this Agreement, and such expenses are payable when due.

2.5      ADDITIONAL COSTS.

         If any law or regulation increases Bank's costs or reduces its income
for any loan, Borrower will pay the increase in cost or reduction in income or
additional expense.

3        CONDITIONS OF LOANS

3.1      CONDITIONS PRECEDENT TO INITIAL CREDIT EXTENSION.

         Bank's obligation to make the initial Credit Extension is subject to
the condition precedent that it receive the agreements, documents and fees it
requires.

3.2      CONDITIONS PRECEDENT TO ALL CREDIT EXTENSIONS.

         Bank's obligations to make each Credit Extension, including the initial
Credit Extension, is subject to the following:

         (a) timely receipt of any Payment/Advance Form; and

         (b) the representations and warranties in Section 5 must be materially
true on the date of the Payment/Advance Form and on the effective date of each
Credit Extension and no Event of Default may have occurred and be continuing, or
result from the Credit Extension. Each Credit Extension is Borrower's
representation and warranty on that date that the representations and warranties
of Section 5 remain true.

4        CREATION OF SECURITY INTEREST

4.1      GRANT OF SECURITY INTEREST.

         Borrower grants Bank a continuing security interest in all presently
existing and later acquired Collateral to secure all Obligations and performance
of each of Borrower's duties under the Loan Documents. Except for Permitted
Liens, any security interest will be a first priority security interest in the
Collateral. Bank may place a "hold" on any deposit account pledged as
Collateral. If this Agreement is terminated, Bank's lien and security interest
in the Collateral will continue until Borrower fully satisfies its Obligations.

4.2      CERTIFICATE OF DEPOSIT COLLATERAL.

         At such times as the Liquidity coverage covenant, as described in
Section 6.7 is not maintained by Borrower, Borrower grants Bank, as additional
security, a first priority security interest in a Certificate of Deposit, held
with Bank, in an amount not less than 100% of the outstanding Obligations.

4.3      CONCERNING REVISED ARTICLE 9 OF THE UNIFORM COMMERCIAL CODE.

         In anticipation of the possible application of the Revised Article 9 of
the Uniform Commercial Code in the form or substantially in the form approved by
the American Law Institute and National Conference Commissioners on Uniform
State Law and contained in the 1999 Official Text of the Uniform Commercial Code
("Revised Article 9"), it is agreed that applying the law of any jurisdiction in
which Revised Article 9 is in effect, the Collateral is all assets of the
Borrower whether or not within the scope of Revised Article 9. The Collateral
shall include, without limitation, the following categories of assets as


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defined in the Code: goods (including inventory, equipment and any accessions
thereto), instruments (including promissory notes), documents, accounts
(including health-care-insurance receivables, and license fees), chattel paper
(whether tangible or electronic), deposit accounts, letter-of-credit rights
(whether or not the letter of credit is evidenced by a writing), commercial tort
claims, securities and all other investment property, general intangibles
(including payment intangibles and software) [BUT EXCLUDING INTELLECTUAL
PROPERTY], supporting obligations and any and all proceeds of any thereof,
wherever located, whether now owned or hereafter acquired.

5        REPRESENTATIONS AND WARRANTIES

         Borrower represents and warrants as follows:

5.1      DUE ORGANIZATION AND AUTHORIZATION.

         Borrower and each Subsidiary is duly existing and in good standing in
its state of formation and qualified and licensed to do business in, and in good
standing in, any state in which the conduct of its business or its ownership of
property requires that it be qualified, except where the failure to do so could
not reasonably be expected to cause a Material Adverse Change.

         The execution, delivery and performance of the Loan Documents have been
duly authorized, and do not conflict with Borrower's formation documents, nor
constitute an event of default under any material agreement by which Borrower is
bound. Borrower is not in default under any agreement to which or by which it is
bound in which the default could reasonably be expected to cause a Material
Adverse Change.

5.2      COLLATERAL.

         Borrower has good title to the Collateral, free of Liens except
Permitted Liens. All Inventory is in all material respects of good and
marketable quality, free from material defects.

5.3      LITIGATION.

         Except as shown in the Schedule, there are no actions or proceedings
pending or, to the knowledge of Borrower's Responsible Officers, threatened by
or against Borrower or any Subsidiary in which a likely adverse decision could
reasonably be expected to cause a Material Adverse Change.

5.4      NO MATERIAL ADVERSE CHANGE IN FINANCIAL STATEMENTS.

         All consolidated financial statements for Borrower, and any Subsidiary,
delivered to Bank fairly present in all material respects Borrower's
consolidated financial condition and Borrower's consolidated results of
operations. There has not been any material deterioration in Borrower's
consolidated financial condition since the date of the most recent financial
statements submitted to Bank.

5.5      SOLVENCY.

         The fair salable value of Borrower's assets (including goodwill minus
disposition costs) exceeds the fair value of its liabilities; the Borrower is
not left with unreasonably small capital after the transactions in this
Agreement; and Borrower is able to pay its debts (including trade debts) as they
mature.

5.6      REGULATORY COMPLIANCE.

         Borrower is not an "investment company" or a company "controlled" by an
"investment company" under the Investment Company Act. Borrower is not engaged
as one of its important activities in extending credit for margin stock (under
Regulations T and U of the Federal Reserve Board of Governors). Borrower has
complied in all material respects with the Federal Fair Labor Standards Act.
Borrower has not violated any laws, ordinances or rules, the violation of which
could reasonably be expected to cause a Material Adverse Change. None of
Borrower's or any Subsidiary's properties or assets has been used by Borrower or
any Subsidiary or, to the best of Borrower's knowledge, by previous


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Persons, in disposing, producing, storing, treating, or transporting any
hazardous substance other than legally. Borrower and each Subsidiary has timely
filed all required tax returns and paid, or made adequate provision to pay, all
material taxes, except those being contested in good faith with adequate
reserves under GAAP. Borrower and each Subsidiary has obtained all consents,
approvals and authorizations of, made all declarations or filings with, and
given all notices to, all government authorities that are necessary to continue
its business as currently conducted, except where the failure to do so could not
reasonably be expected to cause a Material Adverse Change.

5.7      SUBSIDIARIES.

         Borrower does not own any stock, partnership interest or other equity
securities except for Permitted Investments.

5.8      FULL DISCLOSURE.

         No written representation, warranty or other statement of Borrower in
any certificate or written statement given to Bank (taken together with all such
written certificates and written statements to Bank) contains any untrue
statement of a material fact or omits to state a material fact necessary to make
the statements contained in the certificates or statements not misleading. It
being recognized by Bank that the projections and forecasts provided by Borrower
in good faith and based upon reasonable assumptions are not viewed as facts and
that actual results during the period or periods covered by such projections and
forecasts may differ from the projected and forecasted results.

6        AFFIRMATIVE COVENANTS

         Borrower will do all of the following for so long as Bank has an
obligations to lend, or there are outstanding Obligations:

6.1      GOVERNMENT COMPLIANCE.

         Borrower will maintain its and all Subsidiaries' legal existence and
good standing in its jurisdiction of formation and maintain qualification in
each jurisdiction in which the failure to so qualify would reasonably be
expected to cause a material adverse effect on Borrower's business or
operations. Borrower will comply, and have each Subsidiary comply, with all
laws, ordinances and regulations to which it is subject, noncompliance with
which could have a material adverse effect on Borrower's business or operations
or would reasonably be expected to cause a Material Adverse Change.

6.2      FINANCIAL STATEMENTS, REPORTS, CERTIFICATES.

         (a) Borrower will deliver to Bank: (i) as soon as available, but no
later than 30 days after the last day of each month, except December, a company
prepared consolidated balance sheet and income statement covering Borrower's
consolidated operations during the period certified by a Responsible Officer and
in a form acceptable to Bank; (ii) as soon as available, but no later than 120
days after the last day of Borrower's fiscal year, audited consolidated
financial statements prepared under GAAP, consistently applied, together with an
unqualified opinion on the financial statements from an independent certified
public accounting firm reasonably acceptable to Bank; (iii) a prompt report of
any legal actions pending or threatened against Borrower or any Subsidiary that
could result in damages or costs to Borrower or any Subsidiary of $100,000 or
more; and (iv) budgets, sales projections, operating plans or other financial
information Bank reasonably requests.

         (b) Within 30 days after the last day of each month, Borrower will
deliver to Bank with the monthly financial statements a Compliance Certificate
signed by a Responsible Officer in the form of Exhibit C.

         (c) Allow Bank to audit Borrower's Collateral at Borrower's reasonable
expense. Such audits will be conducted only at such times as an Event of Default
has occurred and is continuing.


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6.3      INVENTORY; RETURNS.

         Borrower will keep all Inventory in good and marketable condition, free
from material defects. Returns and allowances between Borrower and its account
debtors will follow Borrower's customary practices as they exist at execution of
this Agreement. Borrower must promptly notify Bank of all returns, recoveries,
disputes and claims, that involve more than $50,000.

6.4      TAXES.

         Borrower will make, and cause each Subsidiary to make, timely payment
of all material federal, state, and local taxes or assessments and will deliver
to Bank, on demand, appropriate certificates attesting to the payment.

6.5      INSURANCE.

         Borrower will keep its business and the Collateral insured for risks
and in amounts, as Bank may reasonably request. Insurance policies will be in a
form, with companies, and in amounts that are satisfactory to Bank in Bank's
reasonable discretion. All property policies will have a lender's loss payable
endorsement showing Bank as an additional loss payee and all liability policies
will show the Bank as an additional insured and provide that the insurer must
give Bank at least 20 days notice before canceling its policy. At Bank's
request, Borrower will deliver certified copies of policies and evidence of all
premium payments. Proceeds payable under any policy will, at Bank's option, be
payable to Bank on account of the Obligations.

6.6      PRIMARY ACCOUNTS AND BALANCES.

         a. Borrower will maintain its primary depository and operating accounts
with Bank.

         b. Money Market Account. Borrower shall maintain with Bank, a money
market account with an amount not less than $2,000,000.00. In the event Borrower
completes an equity financing, Bank agrees that it will examine the Money Market
Account requirement to determine if a change is possible or appropriate, with
the explicit understanding by Borrower that such examination is not a commitment
or proposal to amend the requirement.

         c. In addition, Borrower shall maintain an average minimum monthly
balance of $1,000,000.00 in Bank's money market account or demand deposit
account or investment account.


6.7      FINANCIAL COVENANTS.

         (i) LIQUIDITY COVERAGE. . Borrower will maintain, as of the last day of
each month, a Liquidity coverage of the greater of (a) unrestricted cash and
cash equivalents (including short term marketable securities) equal to 1.5 times
the outstanding Obligations or (b) at least 6 (six) months Cash Burn. "Cash
Burn" is unrestricted cash (prior period) minus unrestricted cash (current
period) plus increases in short and long term borrowings or in equity (or
Subordinated Debt) and minus any increase in short and long term borrowings or
in equity (or Subordinated Debt). In the event Borrower fails to comply with the
foregoing Liquidity coverage it shall not be deemed an Event of Default;
provided that Borrower pledges to Bank cash collateral in the form of a
certificate of deposit held with Bank as described in Section 4.2. Once Borrower
returns to compliance with the Liquidity coverage, such cash collateral shall be
released.

6.8      FURTHER ASSURANCES.

         Borrower will execute any further instruments and take further action
as Bank reasonably requests to perfect or continue Bank's security interest in
the Collateral or to effect the purposes of this Agreement.


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6.9      RIGHT TO INVEST.

         Borrower grants Bank or its affiliates a right (but not an obligation)
to invest up to $250,000.00 in each of Borrower's subsequent rounds of equity
financing (the "Subsequent Financing") on the same terms, conditions and pricing
offered to its investors. Borrower must give Bank with at least 30 days prior
written notice of each Subsequent Financing containing the terms, conditions and
pricing of the Subsequent Financing delivered to: General Counsel, 3003 Tasman
Drive, HG 180, Santa Clara, CA 95054.

7        NEGATIVE COVENANTS

         Borrower will not do any of the following without Bank's prior written
consent, which will not be unreasonably withheld, for so long as Bank has an
obligation to lend and there are any outstanding Obligations:

7.1      DISPOSITIONS.

         Convey, sell, lease, transfer or otherwise dispose of (collectively
"Transfer"), or permit any of its Subsidiaries to Transfer, all or any part of
its business or property, EXCEPT FOR Transfers (i) of Inventory in the ordinary
course of business; (ii) of non-exclusive licenses and similar arrangements for
the use of the property of Borrower or its Subsidiaries in the ordinary course
of business; or (iii) of worn-out or obsolete Equipment.

7.2      CHANGES IN BUSINESS, OWNERSHIP, MANAGEMENT OR BUSINESS LOCATIONS.

         Engage in or permit any of its Subsidiaries to engage in any business
other than the businesses currently engaged in by Borrower or reasonably related
thereto or have a material change in its ownership or management of greater than
25% (other than by the sale of Borrower's equity securities in a public offering
or to venture capital investors so long as Borrower identifies the venture
capital investors prior to the closing of the investment). Borrower will not,
without at least 30 days prior written notice, relocate its chief executive
office or add any new offices or business locations in which Borrower maintains
or stores over $5,000 in Borrower's assets or property.

7.3      MERGERS OR ACQUISITIONS.

         Merge or consolidate, or permit any of its Subsidiaries to merge or
consolidate, with any other Person, or acquire, or permit any of its
Subsidiaries to acquire, all or substantially all of the capital stock or
property of another Person, except where (i) no Event of Default has occurred
and is continuing or would result from such action during the term of this
Agreement and (ii) such transaction would not result in a decrease of more than
25% of Tangible Net Worth. A Subsidiary may merge or consolidate into another
Subsidiary or into Borrower.

7.4      INDEBTEDNESS.

         Create, incur, assume, or be liable for any Indebtedness, or permit any
Subsidiary to do so, other than Permitted Indebtedness.

7.5      ENCUMBRANCE.

         Create, incur, or allow any Lien on any of its property, or assign or
convey any right to receive income, or permit any of its Subsidiaries to do so,
except for Permitted Liens, or permit any Collateral not to be subject to the
first priority security interest granted here, subject to Permitted Liens.


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7.6      DISTRIBUTIONS; INVESTMENTS.

         Directly or indirectly acquire or own any Person, or make any
Investment in any Person, other than Permitted Investments, or permit any of its
Subsidiaries to do so. Pay any dividends or make any distribution or payment or
redeem, retire or purchase any capital stock.

7.7      TRANSACTIONS WITH AFFILIATES.

         Directly or indirectly enter into or permit to exist any material
transaction with any Affiliate of Borrower except for transactions that are in
the ordinary course of Borrower's business, upon fair and reasonable terms that
are no less favorable to Borrower than would be obtained in an arm's length
transaction with a nonaffiliated Person.

7.8      SUBORDINATED DEBT.

         Make or permit any payment on any Subordinated Debt, except under the
terms of the Subordinated Debt, or amend any provision in any document relating
to the Subordinated Debt without Bank's prior written consent.

7.9      COMPLIANCE.

         Become an "investment company" or a company controlled by an
"investment company," under the Investment Company Act of 1940 or undertake as
one of its important activities extending credit to purchase or carry margin
stock, or use the proceeds of any Credit Extension for that purpose; fail to
meet the minimum funding requirements of ERISA, permit a Reportable Event or
Prohibited Transaction, as defined in ERISA, to occur; fail to comply with the
Federal Fair Labor Standards Act or violate any other law or regulation, if the
violation could reasonably be expected to have a material adverse effect on
Borrower's business or operations or would reasonably be expected to cause a
Material Adverse Change, or permit any of its Subsidiaries to do so.

8        EVENTS OF DEFAULT

         Any one of the following is an Event of Default:

8.1      PAYMENT DEFAULT.

         If Borrower fails to pay any of the Obligations within 3 days after
their due date. During the additional period the failure to cure the default is
not an Event of Default (but no Credit Extension will be made during the cure
period);

8.2      COVENANT DEFAULT.

         If Borrower does not perform any obligation in Section 6 or violates
any covenant in Section 7 or does not perform or observe any other material
term, condition or covenant in this Agreement, any Loan Documents, or in any
agreement between Borrower and Bank and as to any default under a term,
condition or covenant that can be cured, has not cured the default within 10
days after it occurs, or if the default cannot be cured within 10 days or cannot
be cured after Borrower's attempts within 10 day period, and the default may be
cured within a reasonable time, then Borrower has an additional period (of not
more than 30 days) to attempt to cure the default. During the additional time,
the failure to cure the default is not an Event of Default (but no Credit
Extensions will be made during the cure period);

8.3      MATERIAL ADVERSE CHANGE.

         If there (i) occurs a material adverse change in the business,
operations, or condition (financial or otherwise) of the Borrower, or (ii) is a
material impairment of the prospect of repayment of any portion of the
Obligations; or (iii) is a material impairment of the value or priority of
Bank's security interests in the Collateral.


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8.4      ATTACHMENT.

         If any material portion of Borrower's assets is attached, seized,
levied on, or comes into possession of a trustee or receiver and the attachment,
seizure or levy is not removed in 10 days, or if Borrower is enjoined,
restrained, or prevented by court order from conducting a material part of its
business or if a judgment or other claim becomes a Lien on a material portion of
Borrower's assets, or if a notice of lien, levy, or assessment is filed against
any of Borrower's assets by any government agency and not paid within 10 days
after Borrower receives notice. These are not Events of Default if stayed or if
a bond is posted pending contest by Borrower (but no Credit Extensions will be
made during the cure period);

8.5      INSOLVENCY.

         If Borrower becomes insolvent or if Borrower begins an Insolvency
Proceeding or an Insolvency Proceeding is begun against Borrower and not
dismissed or stayed within 30 days (but no Credit Extensions will be made before
any Insolvency Proceeding is dismissed);

8.6      OTHER AGREEMENTS.

         If there is a default in any agreement between Borrower and a third
party that gives the third party the right to accelerate any Indebtedness
exceeding $100,000 or that could cause a Material Adverse Change;

8.7      JUDGMENTS.

         If a money judgment(s) in the aggregate of at least $50,000 is rendered
against Borrower and is unsatisfied and unstayed for 10 days (but no Credit
Extensions will be made before the judgment is stayed or satisfied); or

8.8      MISREPRESENTATIONS.

         If Borrower or any Person acting for Borrower makes any material
misrepresentation or material misstatement now or later in any warranty or
representation in this Agreement or in any writing delivered to Bank or to
induce Bank to enter this Agreement or any Loan Document.

9        BANK'S RIGHTS AND REMEDIES

9.1      RIGHTS AND REMEDIES.

         When an Event of Default occurs and continues Bank may, without notice
or demand, do any or all of the following:

         (a) Declare all Obligations immediately due and payable (but if an
Event of Default described in Section 8.5 occurs all Obligations are immediately
due and payable without any action by Bank);

         (b) Stop advancing money or extending credit for Borrower's benefit
under this Agreement or under any other agreement between Borrower and Bank;

         (c) Settle or adjust disputes and claims directly with account debtors
for amounts, on terms and in any order that Bank considers advisable;

         (d) Make any payments and do any acts it considers necessary or
reasonable to protect its security interest in the Collateral. Borrower will
assemble the Collateral if Bank requires and make it available as Bank
designates. Bank may enter premises where the Collateral is located, take and
maintain possession of any part of the Collateral, and pay, purchase, contest,
or compromise any Lien which appears to be prior or superior to its security
interest and pay all expenses incurred. Borrower


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<Page>


grants Bank a license to enter and occupy any of its premises, without charge,
to exercise any of Bank's rights or remedies;

         (e) Apply to the Obligations any (i) balances and deposits of Borrower
it holds, or (ii) any amount held by Bank owing to or for the credit or the
account of Borrower;

         (f) Ship, reclaim, recover, store, finish, maintain, repair, prepare
for sale, advertise for sale, and sell the Collateral; and

         (g) Dispose of the Collateral according to the Code.

9.2      POWER OF ATTORNEY.

         Effective only when an Event of Default occurs and continues, Borrower
irrevocably appoints Bank as its lawful attorney to: (i) endorse Borrower's name
on any checks or other forms of payment or security; (ii) sign Borrower's name
on any invoice or bill of lading for any account or drafts against account
debtors, (iii) make, settle, and adjust all claims under Borrower's insurance
policies; and (iv) transfer the Collateral into the name of Bank or a third
party as the Code permits. Bank may exercise the power of attorney to sign
Borrower's name on any documents necessary to perfect or continue the perfection
of any security interest regardless of whether an Event of Default has occurred.
Bank's appointment as Borrower's attorney in fact, and all of Bank's rights and
powers, coupled with an interest, are irrevocable until all Obligations have
been fully repaid and performed and Bank's obligation to provide Credit
Extensions terminates.

9.3      BANK EXPENSES.

         If Borrower fails to pay any amount or furnish any required proof of
payment to third persons, Bank may make all or part of the payment or obtain
insurance policies required in Section 6.5, and take any action under the
policies Bank deems prudent. Any amounts paid by Bank are Bank Expenses and
immediately due and payable, bearing interest at the then applicable rate and
secured by the Collateral. No payments by Bank are deemed an agreement to make
similar payments in the future or Bank's waiver of any Event of Default.

9.4      BANK'S LIABILITY FOR COLLATERAL.

         If Bank complies with reasonable banking practices and Section 9-207 of
the Code, it is not liable for: (a) the safekeeping of the Collateral; (b) any
loss or damage to the Collateral; (c) any diminution in the value of the
Collateral; or (d) any act or default of any carrier, warehouseman, bailee, or
other person. Borrower bears all risk of loss, damage or destruction of the
Collateral.

9.5      REMEDIES CUMULATIVE.

         Bank's rights and remedies under this Agreement, the Loan Documents,
and all other agreements are cumulative. Bank has all rights and remedies
provided under the Code, by law, or in equity. Bank's exercise of one right or
remedy is not an election, and Bank's waiver of any Event of Default is not a
continuing waiver. Bank's delay is not a waiver, election, or acquiescence. No
waiver is effective unless signed by Bank and then is only effective for the
specific instance and purpose for which it was given.

9.6      DEMAND WAIVER.

         Borrower waives demand, notice of default or dishonor, notice of
payment and nonpayment, notice of any default, nonpayment at maturity, release,
compromise, settlement, extension, or renewal of accounts, documents,
instruments, chattel paper, and guarantees held by Bank on which Borrower is
liable.

10       NOTICES


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<Page>


         All notices or demands by any party about this Agreement or any other
related agreement must be in writing and be personally delivered or sent by an
overnight delivery service, by certified mail, postage prepaid, return receipt
requested, or by telefacsimile to the addresses set forth at the beginning of
this Agreement. A party may change its notice address by giving the other party
written notice.

11       CHOICE OF LAW, VENUE AND JURY TRIAL WAIVER

         California law governs the Loan Documents without regard to principles
of conflicts of law. Borrower and Bank each submit to the exclusive jurisdiction
of the State and Federal courts in San Diego County, California.

BORROWER AND BANK EACH WAIVE THEIR RIGHT TO A JURY TRIAL OF ANY CLAIM OR CAUSE
OF ACTION ARISING OUT OF ANY OF THE LOAN DOCUMENTS OR ANY CONTEMPLATED
TRANSACTION, INCLUDING CONTRACT, TORT, BREACH OF DUTY AND ALL OTHER CLAIMS. THIS
WAIVER IS A MATERIAL INDUCEMENT FOR BOTH PARTIES TO ENTER INTO THIS AGREEMENT.
EACH PARTY HAS REVIEWED THIS WAIVER WITH ITS COUNSEL.

12       GENERAL PROVISIONS

12.1     SUCCESSORS AND ASSIGNS.

         This Agreement binds and is for the benefit of the successors and
permitted assigns of each party. Borrower may not assign this Agreement or any
rights under it without Bank's prior written consent which may be granted or
withheld in Bank's discretion. Bank has the right, without the consent of or
notice to Borrower, to sell, transfer, negotiate, or grant participation in all
or any part of, or any interest in, Bank's obligations, rights and benefits
under this Agreement.

12.2     INDEMNIFICATION.

         Borrower will indemnify, defend and hold harmless Bank and its
officers, employees, and agents against: (a) all obligations, demands, claims,
and liabilities asserted by any other party in connection with the transactions
contemplated by the Loan Documents; and (b) all losses or Bank Expenses
incurred, or paid by Bank from, following, or consequential to transactions
between Bank and Borrower (including reasonable attorneys fees and expenses),
except for losses caused by Bank's gross negligence or willful misconduct.

12.3     TIME OF ESSENCE.

         Time is of the essence for the performance of all obligations in this
Agreement.

12.4     SEVERABILITY OF PROVISION.

         Each provision of this Agreement is severable from every other
provision in determining the enforceability of any provision.

12.5     AMENDMENTS IN WRITING, INTEGRATION.

         All amendments to this Agreement must be in writing and signed by
Borrower and Bank. This Agreement represents the entire agreement about this
subject matter, and supersedes prior negotiations or agreements. All prior
agreements, understandings, representations, warranties, and negotiations
between the parties about the subject matter of this Agreement merge into this
Agreement and the Loan Documents.


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<Page>


12.6     COUNTERPARTS.

         This Agreement may be executed in any number of counterparts and by
different parties on separate counterparts, each of which, when executed and
delivered, are an original, and all taken together, constitute one Agreement.

12.7     SURVIVAL.

         All covenants, representations and warranties made in this Agreement
continue in full force while any Obligations remain outstanding. The obligations
of Borrower in Section 12.2 to indemnify Bank will survive until all statutes of
limitations for actions that may be brought against Bank have run.

12.8     CONFIDENTIALITY.

         In handling any confidential information, Bank will exercise the same
degree of care that it exercises for its own proprietary information, but
disclosure of information may be made (i) to Bank's subsidiaries or affiliates
in connection with their business with Borrower, (ii) to prospective transferees
or purchasers of any interest in the loans (provided, however, Bank shall use
commercially reasonable efforts in obtaining such prospective transferee or
purchasers agreement of the terms of this provision), (iii) as required by law,
regulation, subpoena, or other order, (iv) as required in connection with Bank's
examination or audit and (v) as Bank considers appropriate exercising remedies
under this Agreement. Confidential information does not include information that
either: (a) is in the public domain or in Bank's possession when disclosed to
Bank, or becomes part of the public domain after disclosure to Bank; or (b) is
disclosed to Bank by a third party, if Bank does not know that the third party
is prohibited from disclosing the information.

12.9     EFFECT OF AMENDMENT AND RESTATEMENT.

         This Agreement is intended to and does completely amend and restate,
without novation, the Original Agreement. All credit extensions or loans
outstanding under the Original Agreement are and shall continue to be
outstanding under this Agreement. All security interests granted under the
Original Agreement are hereby confirmed and ratified and shall continue to
secure all Obligations under this Agreement.

12.10    ATTORNEYS' FEES, COSTS AND EXPENSES.

         In any action or proceeding between Borrower and Bank arising out of
the Loan Documents, the prevailing party will be entitled to recover its
reasonable attorneys' fees and other reasonable costs and expenses incurred, in
addition to any other relief to which it may be entitled.

13       DEFINITIONS

13.1     DEFINITIONS.

         In this Agreement:

         "AFFILIATE" of a Person is a Person that owns or controls directly or
indirectly the Person, any Person that controls or is controlled by or is under
common control with the Person, and each of that Person's senior executive
officers, directors, partners and, for any Person that is a limited liability
company, that Person's managers and members.

         "BANK EXPENSES" are all audit fees and expenses and reasonable costs
and expenses (including reasonable attorneys' fees and expenses) for preparing,
negotiating, administering, defending and enforcing the Loan Documents
(including appeals or Insolvency Proceedings).


                                       15

<Page>


         "BORROWER'S BOOKS" are all Borrower's books and records including
ledgers, records regarding Borrower's assets or liabilities, the Collateral,
business operations or financial condition and all computer programs or discs or
any equipment containing the information.

         "BUSINESS DAY" is any day that is not a Saturday, Sunday or a day on
which the Bank is closed.

         "CASH BURN" is defined in Section 6.7.

         "CLOSING DATE" is the date of this Agreement.

         "CODE" is the Uniform Commercial Code, as applicable.

         "COLLATERAL" is the property described on EXHIBIT A.

         "COMMITTED EQUIPMENT LINE" is a Credit Extension of up to $2,000,000.

         "CONTINGENT OBLIGATION" is, for any Person, any direct or indirect
liability, contingent or not, of that Person for (i) any indebtedness, lease,
dividend, letter of credit or other obligation of another such as an obligation
directly or indirectly guaranteed, endorsed, co-made, discounted or sold with
recourse by that Person, or for which that Person is directly or indirectly
liable; (ii) any obligations for undrawn letters of credit for the account of
that Person; and (iii) all obligations from any interest rate, currency or
commodity swap agreement, interest rate cap or collar agreement, or other
agreement or arrangement designated to protect a Person against fluctuation in
interest rates, currency exchange rates or commodity prices; but "Contingent
Obligation" does not include endorsements in the ordinary course of business.
The amount of a Contingent Obligation is the stated or determined amount of the
primary obligation for which the Contingent Obligation is made or, if not
determinable, the maximum reasonably anticipated liability for it determined by
the Person in good faith; but the amount may not exceed the maximum of the
obligations under the guarantee or other support arrangement.

         "CREDIT EXTENSION" is each Equipment Advance, Term Loan 1, Term Loan 2
or any other extension of credit by Bank for Borrower's benefit.

         "EQUIPMENT" is all present and future machinery, equipment, tenant
improvements, furniture, fixtures, vehicles, tools, parts and attachments in
which Borrower has any interest.

         "EQUIPMENT ADVANCE" is defined in Section 2.1.1.

         "EQUIPMENT AVAILABILITY END DATE" is defined in Section 2.1.1.

         "EQUIPMENT MATURITY DATE" is defined in Section 2.1.1.

         "ERISA" is the Employment Retirement Income Security Act of 1974, and
its regulations.

         "GAAP" is generally accepted accounting principles.

         "INDEBTEDNESS" is (a) indebtedness for borrowed money or the deferred
price of property or services, such as reimbursement and other obligations for
surety bonds and letters of credit, (b) obligations evidenced by notes, bonds,
debentures or similar instruments, (c) capital lease obligations and (d)
Contingent Obligations.

         "INSOLVENCY PROCEEDING" are proceedings by or against any Person under
the United States Bankruptcy Code, or any other bankruptcy or insolvency law,
including assignments for the benefit of creditors, compositions, extensions
generally with its creditors, or proceedings seeking reorganization,
arrangement, or other relief.

         "INVENTORY" is present and future inventory in which Borrower has any
interest, including merchandise, raw materials, parts, supplies, packing and
shipping materials, work in process and finished


                                       16

<Page>


products intended for sale or lease or to be furnished under a contract of
service, of every kind and description now or later owned by or in the custody
or possession, actual or constructive, of Borrower, including inventory
temporarily out of its custody or possession or in transit and including returns
on any accounts or other proceeds (including insurance proceeds) from the sale
or disposition of any of the foregoing and any documents of title.

         "INVESTMENT" is any beneficial ownership of (including stock,
partnership interest or other securities) any Person, or any loan, advance or
capital contribution to any Person.

         "LIEN" is a mortgage, lien, deed of trust, charge, pledge, security
interest or other encumbrance.

         "LOAN DOCUMENTS" are, collectively, this Agreement, any note, or notes
or guaranties executed by Borrower or Guarantor, and any other present or future
agreement between Borrower and/or for the benefit of Bank in connection with
this Agreement, all as amended, extended or restated.

         "MAKE-WHOLE PREMIUM" is an amount equal to 3% of the outstanding
Equipment Advances if the prepayment is made on or before the first anniversary
of the date hereof; 2% of the outstanding Equipment Advances if the prepayment
is made on or after the first anniversary hereof but before the second
anniversary hereof; and 1% of outstanding Equipment Advances if the prepayment
is made on or after the second anniversary hereof but before the third
anniversary hereof but before the Equipment Maturity Date.

         "MATERIAL ADVERSE CHANGE" is defined in Section 8.3.

         "OBLIGATIONS" are debts, principal, interest, Bank Expenses and other
amounts Borrower owes Bank now or later, including cash management services,
letters of credit and foreign exchange contracts, if any and including interest
accruing after Insolvency Proceedings begin and debts, liabilities, or
obligations of Borrower assigned to Bank.

         "ORIGINAL AGREEMENT" has the meaning set forth in recital paragraph A.

         "PERMITTED INDEBTEDNESS" is:

         (a) Borrower's indebtedness to Bank under this Agreement or any other
Loan Document;

         (b) Indebtedness existing on the Closing Date and shown on the
Schedule;

         (c) Subordinated Debt;

         (d) Indebtedness to trade creditors incurred in the ordinary course of
business; and

         (e) Indebtedness secured by Permitted Liens.

         "PERMITTED INVESTMENTS" are:

         (a) Investments existing on the Closing Date and those consistent with
Borrower's Investment Policy, dated June 14, 1996; and

         (b) (i) marketable direct obligations issued or unconditionally
guaranteed by the United States or its agency or any State maturing within 1
year from its acquisition, (ii) commercial paper maturing no more than 1 year
after its creation and having the highest rating from either Standard & Poor's
Corporation or Moody's Investors Service, Inc. or consistent with Borrower's
Investment Policy, and (iii) Bank's certificates of deposit issued maturing no
more than 1 year after issue.


                                       17

<Page>


         "PERMITTED LIENS" are:

         (a) Liens existing on the Closing Date and shown on the Schedule or
arising under this Agreement or other Loan Documents;

         (b) Liens for taxes, fees, assessments or other government charges or
levies, either not delinquent or being contested in good faith and for which
Borrower maintains adequate reserves on its Books, IF they have no priority over
any of Bank's security interests;

         (c) Purchase money Liens (i) on Equipment acquired or held by Borrower
or its Subsidiaries incurred for financing the acquisition of the Equipment, or
(ii) existing on equipment when acquired, IF the Lien is confined to the
property and improvements and the proceeds of the equipment;

         (d) Licenses or sublicenses granted in the ordinary course of
Borrower's business and any interest or title of a licensor or under any license
or sublicense, IF the licenses and sublicenses permit granting Bank a security
interest;

         (e) Leases or subleases granted in the ordinary course of Borrower's
business, including in connection with Borrower's leased premises or leased
property;

         (f) Liens incurred in the extension, renewal or refinancing of the
indebtedness secured by Liens described in (a) through (c), BUT any extension,
renewal or replacement Lien must be limited to the property encumbered by the
existing Lien and the principal amount of the indebtedness may not increase.

         "PERSON" is any individual, sole proprietorship, partnership, limited
liability company, joint venture, company association, trust, unincorporated
organization, association, corporation, institution, public benefit corporation,
firm, joint stock company, estate, entity or government agency.

         "PREPAYMENT FEE" is a fee on any portion of the Term Loan 1 with a
fixed interest rate (the "Fixed Obligation") paid before the payment due date.
"Base Interest Rate" means Bank's initial cost of funding the Fixed Obligations.
The Prepayment Fee is calculated as follows: First, Bank determines a "Current
Market Rate" based on what the Bank would receive if it loaned the remaining
amount on the prepayment date in a wholesale funding market matching maturity,
remaining principal and interest amounts and principal and interest payment
dates (the aggregate payments received are the "Current Market Rate Amount").
Bank may select any wholesale funding market rate as the Current Market Rate.
Second, Bank will take the prepayment amount and calculate the present value of
each remaining principal and interest payment which, without prepayment, the
Bank would have received during the term of the Fixed Obligations using the Base
Interest Rate. The sum of the present value calculations is the "Mark to Market
Amount." Third, the Bank will subtract the Current Market Rate Amount from the
Mark to Market Amount. Any amount greater than zero is the Prepayment Fee.

         "PRIME RATE" is Bank's most recently announced "prime rate," even if it
is not Bank's lowest rate.

         "REMAINING MONTHS LIQUIDITY" is defined in Section 6.7.

         "RESPONSIBLE OFFICER" is each of the Chief Executive Officer, the
President, the Chief Financial Officer, the Director of Finance and the
Controller of Borrower.

         "SCHEDULE" is any attached schedule of exceptions.

         "SUBORDINATED DEBT" is debt incurred by Borrower subordinated to
Borrower's indebtedness owed to Bank and which is reflected in a written
agreement in a manner and form acceptable to Bank and approved by Bank in
writing.


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<Page>


         "SUBSIDIARY" is for any Person, or any other business entity of which
more than 50% of the voting stock or other equity interests is owned or
controlled, directly or indirectly, by the Person or one or more Affiliates of
the Person.

         "TANGIBLE NET WORTH" is, on any date, the consolidated total assets of
Borrower and its Subsidiaries MINUS, (i) any amounts attributable to (a)
goodwill, (b) intangible items such as unamortized debt discount and expense,
Patents, trade and service marks and names, Copyrights and research and
development expenses except prepaid expenses, and (c) reserves not already
deducted from assets, AND (ii) Total Liabilities.

         "TERM LOAN 1" is a loan of $305,555.50.

         "TERM LOAN 2" is a loan of $1,388,888.95.

         "TERM LOAN 1 MATURITY DATE" is April 30, 2002.

         "TERM LOAN 2 MATURITY DATE" is June 15, 2003.

         "TOTAL LIABILITIES" is on any day, obligations that should, under GAAP,
be classified as liabilities on Borrower's consolidated balance sheet, including
all Indebtedness, and current portion Subordinated Debt allowed to be paid, but
excluding all other Subordinated Debt.

         "TREASURY YIELD PERCENTAGE" is defined as the most recent weekly
average yield on actively traded U.S. Treasury obligations having a final
maturity approximate to the then remaining average life of the principal amount
to be repaid as determined by reference to the week ending figures published in
the most recent Federal Reserve Statistical Release which shall become available
at least two business days prior to the date as of which such yield is to be
determined, or if a Statistical Release is not then published, the arithmetic
average (rounded to the nearest .01%) of the per annum yields to maturity for
each business day during the week ending at least two business days prior to the
date such determination is made, of all issues of actively traded marketable
United States Treasury fixed interest rate securities with a constant maturity
equal to, or not more than 30 days longer or 30 days shorter than the average
life of the payments of principal and interest that are avoided by any
prepayment (excluding all such securities which can be surrendered at the option
of the holder at the face value of payment of any Federal estate tax, or which
provide for tax benefits to the holder).


BORROWER:

MITOKOR


By: /s/ Walter H. Moos
   ---------------------------------

Title: CEO, Chairman of the Board
      ------------------------------


BANK:

SILICON VALLEY BANK


By: /s/ Linda S. LeBeau
   ---------------------------------

Title:  SVP
      ------------------------------


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