Exhibit 10.34

LOAN AND SECURITY AGREEMENT

THIS LOAN AND SECURITY AGREEMENT(this "Agreement") dated as of
March 14, 2008 (the "Effective Date") betweenOXFORD FINANCE CORPORATION, a Delaware corporation
with an office located at 133 N. Fairfax Street, Alexandria, VA 22314("Lender")andMETABASIS
THERAPEUTICS, INC.a Delaware corporation with an office located at 11119 North Torrey Pines Road, La Jolla, CA 92037 and ARAMED, INC.a Delaware corporation with an
office located at 11119 North Torrey Pines Road, La Jolla, CA 92037 (jointly and severally,
individually and collectively, the "Borrower"), provides the terms on which Lender shall lend to Borrower and Borrower shall repay Lender. The parties
agree as follows:

1ACCOUNTING AND OTHER TERMS

Accounting
terms not defined in this Agreement shall be construed following GAAP. Calculations and determinations must be made following GAAP (except for non-compliance with
FAS 123R in monthly reporting). Capitalized terms not otherwise defined in this Agreement shall have the meanings set forth in Section 13. All other terms contained in this Agreement,
unless otherwise indicated, shall have the meaning provided by the Code to the extent such terms are defined therein.

2LOAN AND TERMS OF PAYMENT



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3CONDITIONS OF LOANS



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4CREATION OF SECURITY INTEREST



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5REPRESENTATIONS AND WARRANTIES

Borrower
represents and warrants as follows:



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6AFFIRMATIVE COVENANTS

Borrower
shall do all of the following:



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7NEGATIVE COVENANTS

Borrower
shall not do any of the following without Lender's prior written consent:



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8EVENTS OF DEFAULT

Any
one of the following shall constitute an event of default (an "Event of Default") under this Agreement:



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9RIGHTS AND REMEDIES



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10NOTICES

All
notices, consents, requests, approvals, demands, or other communication (collectively, "Communication") by any party to this Agreement
or any other Loan Document must be in writing and shall be deemed to have been validly served, given, or delivered: (a) upon the earlier of actual receipt and three (3) Business Days
after deposit in the U.S. mail, first class, registered or certified mail return receipt requested, with proper postage prepaid; (b) upon transmission, when sent by electronic mail (if an email
address is specified herein) or facsimile transmission; (c) one (1) Business Day after deposit with a reputable overnight courier with all charges prepaid; or (d) when delivered,
if hand-delivered by messenger, all of which shall be addressed to the party to be notified and sent to the address, facsimile number, or email address indicated below. Either, Lender or
Borrower may change its address or facsimile number by giving the other party written notice thereof in accordance with the terms of this Section 10.

If to Borrower:

Metabasis Therapeutics, Inc.11119 North Torrey Pines RoadLa Jolla, CA 92037Attn: Chief Financial OfficerFax: 858-587-2770If to Oxford:

Oxford Finance Corporation133 North Fairfax StreetAlexandria, Virginia 22314Attention: General CounselFax: (703) 519-5225


11CHOICE OF LAW, VENUE AND JURY TRIAL WAIVER

Virginia
law governs the Loan Documents (other than the Warrant) without regard to principles of conflicts of law. Borrower and Lender each submit to the exclusive jurisdiction of the
State and Federal

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courts
in the Commonwealth of Virginia. Notwithstanding the foregoing, nothing in this Agreement shall be deemed to operate to preclude Lender from bringing suit or taking other legal action in any
other jurisdiction to realize on the Collateral or any other security for the Obligations, or to enforce a judgment or other court order in favor of Lender. Borrower expressly submits and consents in
advance to such jurisdiction in any action or suit commenced in any such court, and Borrower hereby waives any objection that it may have based upon lack of personal jurisdiction, improper venue, or
forum non conveniens and hereby consents to the granting of such legal or equitable relief as is deemed appropriate by such court. Borrower hereby waives personal service of the summons, complaints,
and other process issued in such action or suit and agrees that service of such summons, complaints, and other process may be made by registered or certified mail addressed to Borrower at the address
set forth in Section 10 of this Agreement and that service so made shall be deemed completed upon the earlier to occur of Borrower's actual receipt thereof or three (3) days after
deposit in the U.S. mails, proper postage prepaid.

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

12GENERAL PROVISIONS



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13DEFINITIONS



"Account" is any "account" as defined in the Code with such additions to such term as may hereafter be made, and includes, without
limitation, all accounts receivable and other sums owing to Borrower.

"Account Debtor" is any "account debtor" as defined in the Code with such additions to such term as may hereafter be made.

"Affiliate" of any 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.

"Agreement" is defined in the preamble hereof.

"Amortization Date" is October 1, 2008.

"Board" means Borrower's board of directors.

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"Borrower" is defined in the preamble hereof.

"Borrower's Books" are all Borrower's books and records including ledgers, federal and state tax returns, records regarding Borrower's
assets or liabilities, the Collateral, business operations or financial condition, and all computer programs or storage or any equipment containing such information.

"Borrowing Resolutions" are, with respect to any Person, those resolutions adopted by such Person's Board of Directors and delivered by
such Person to Lender approving the Loan Documents to which such Person is a party and the transactions contemplated thereby, together with a certificate executed by its secretary on behalf of such
Person certifying that (a) such Person has the authority to execute, deliver, and perform its obligations under each of the Loan Documents to which it is a party, (b) that attached as
Exhibit A to such certificate is a true, correct, and complete copy of the resolutions then in full force and effect authorizing and ratifying the execution, delivery, and performance by such
Person of the Loan Documents to which it is a party, (c) the name(s) of the Person(s) authorized to execute the Loan Documents on behalf of such Person, together with a sample of the true
signature(s) of such Person(s), and (d) that Lender may conclusively rely on such certificate unless and until such Person shall have delivered to Lender a further certificate canceling or
amending such prior certificate.

"Business Day" is any day that is not a Saturday, Sunday or a day on which Lender is closed.

"Cash Equivalents"are (a) marketable direct obligations issued or unconditionally guaranteed by the United States or any agency or
any State thereof having maturities of not more than one (1) year from the date of acquisition; and (b) commercial paper maturing no more than one (1) year after its creation and
having the highest rating from either Standard & Poor's Ratings Group or Moody's Investors Service, Inc. Notwithstanding the foregoing, Cash Equivalents does not include and each
Borrower and Subsidiary is prohibited from purchasing, purchasing participations in, entering into any type of swap or other equivalent derivative transaction, or otherwise holding or engaging in any
ownership interest in any type of debt instrument, including, without limitation, any corporate or municipal bonds with a long-term nominal maturity for which the interest rate is reset
through a dutch auction and more commonly referred to as an auction rate security.

"Claims" are defined in Section 12.2.

"Code" is the Uniform Commercial Code, as the same may, from time to time, be enacted and in effect in the Commonwealth of Virginia
provided, that, to the extent that the Code is used to define
any term herein or in any Loan Document and such term is defined differently in different Articles or Divisions of the Code, the definition of such term contained in Article or Division 9 shall
govern; provided further, that in the event that, by reason of mandatory provisions of law, any or all of the attachment, perfection, or priority of, or remedies with respect to, Lender's Lien on any
Collateral is governed by the Uniform Commercial Code in effect in a jurisdiction other than the Commonwealth of Virginia, the term "Code" shall mean
the Uniform Commercial Code as enacted and in effect in such other jurisdiction solely for purposes on the provisions thereof relating to such attachment, perfection, priority, or remedies and for
purposes of definitions relating to such provisions.

"Collateral" is any and all properties, rights and assets of Borrower described on Exhibit A.

"Collateral Account" is any Deposit Account, Securities Account, or Commodity Account.

"Commodity Account" is any "commodity account" as defined in the Code with such additions to such term as may hereafter be made.

"Communication" is defined in Section 10.

"Compliance Certificate" is that certain certificate in the form attached hereto as Exhibit C.

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"Contingent Obligation" is, for any Person, any direct or indirect liability, contingent or not, of that Person for (a) 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; (b) any obligations for undrawn letters of credit for the account of that Person; and (c) 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 any guarantee or other support arrangement.

"Control Agreement" is any control agreement entered into among the depository institution at which Borrower maintains a Deposit Account
or the securities intermediary or commodity intermediary at which Borrower maintains a Securities Account or a Commodity Account, Borrower, and Lender pursuant to which Lender obtains control (within
the meaning of the Code) for the benefit of the Lenders over such Deposit Account, Securities Account, or Commodity Account.

"Credit Extension" is the Term Loan.

"Default" is any event which with notice or passage of time or both, would constitute an Event of Default.

"Default Rate" is defined in Section 2.2(b).

"Deposit Account" is any "deposit account" as defined in the Code with such additions to such term as may hereafter be made.

"Designated Deposit Account" is Borrower's deposit account, account number 1450-8-07652, maintained with
Bank of America.

"Dollars," "dollars" and
"$" each mean lawful money of the United States.

"Draw Period" is the period of time from the Effective Date through the earliest to occur of (a)March 14, 2008, and (b) an
Event of Default.

"Effective Date" is defined in the preamble of this Agreement.

"Equipment" is all "equipment" as defined in the Code with such additions to such term as may hereafter be made, and includes without
limitation all machinery, fixtures, goods, vehicles (including motor vehicles and trailers), and any interest in any of the foregoing.

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

"Event of Default" is defined in Section 8.

"Final Payment"is a payment (in addition to and not a substitution for the regular monthly payments of principal plus accrued interest)
equal to the amount of the Term Loan multiplied by the Final Payment Percentage and due on the earliest to occur of (a) the final Payment Date for such Term Loan, (b) the acceleration of
such Term Loan pursuant to Section 2.1.1(d) hereof, and (c) prepayment of the Term Loan pursuant to Section 2.1.1(e) hereof.

"Final Payment Percentage" is, for each Term Loan, four percent (4.0%).

"Funding Date" is any date on which a Credit Extension is made to or on account of Borrower which shall be a Business Day.

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"GAAP" is generally accepted accounting principles set forth in the opinions and pronouncements of the Accounting Principles Board of the
American Institute of Certified Public Accountants and statements and pronouncements of the Financial Accounting Standards Board or in such other statements by such other Person as may be approved by
a significant segment of the accounting profession, which are applicable to the circumstances as of the date of determination.

"General Intangibles" is all "general intangibles" as defined in the Code in effect on the date hereof with such additions to such term as
may hereafter be made, and includes without limitation, all copyright rights, copyright applications, copyright registrations and like protections in each work of authorship and derivative work,
whether published or unpublished, any patents, trademarks, service marks and, to the extent permitted under applicable law, any applications therefor, whether registered or not, any trade secret
rights, including any rights to unpatented inventions, payment intangibles, royalties, contract rights, goodwill, franchise agreements, purchase orders, customer lists, route lists, telephone numbers,
domain names, claims, income and other tax refunds, security and other deposits, options to purchase or sell real or personal property, rights in all litigation presently or hereafter pending (whether
in contract, tort or otherwise), insurance policies (including without limitation key man, property damage, and business interruption insurance), payments of insurance and rights to payment of any
kind.

"Governmental Approval" is any consent, authorization, approval, order, license, franchise, permit, certificate, accreditation,
registration, filing or notice, of, issued by, from or to, or other act by or in respect of, any Governmental Authority.

"Governmental Authority" is any nation or government, any state or other political subdivision thereof, any agency, authority,
instrumentality, regulatory body, court, central bank or other entity exercising executive, legislative, judicial, taxing, regulatory or administrative functions of or pertaining to government, any
securities exchange and any self-regulatory organization.

"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" is any proceeding 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 all "inventory" as defined in the Code in effect on the date hereof with such additions to such term as may hereafter be
made, and includes without limitation all merchandise, raw materials, parts, supplies, packing and shipping materials, work in process and finished products, including without limitation such
inventory as is temporarily out of Borrower's custody or possession or in transit and including any returned goods and any documents of title representing any of the above.

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

"Lender's Expenses" are all audit fees and expenses, costs, and expenses (including reasonable attorneys' fees and expenses) for
preparing, amending, negotiating, administering, defending and enforcing the Loan Documents (including, without limitation, those incurred in connection with appeals or Insolvency Proceedings) or
otherwise incurred with respect to Borrower.

"LIBOR Rate" means the rate of interest per annum determined by Lender to be the rate of interest at which deposits in United States
Dollars are offered to Lender in the London interbank market (rounded upward, if necessary, to the nearest 1/100th of one percent (0.01%)) in which Lender

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customarily
participates for a period of time equal to ninety (90) days and in an amount approximately equal to the amount of such Term Loan.

"LIBOR Rate Margin" is six and seventy-five one-hundredths percentage points (6.75%) per annum.

"Lien" is a claim, mortgage, deed of trust, levy, charge, pledge, security interest or other encumbrance of any kind, whether voluntarily
incurred or arising by operation of law or otherwise against any property.

"Loan Documents" are, collectively, this Agreement, the Warrant, the Perfection Certificate, any note, or notes or guaranties executed by
Borrower, and any other present or future agreement between Borrower and/or for the benefit of Lender in connection with this Agreement, all as amended, restated, or otherwise modified.

"Material Adverse Change"is any material adverse change in the general affairs, senior management, results of operations, or financial
condition of Borrower, whether or not arising from transactions in the ordinary course of business, that is likely to impair the ability of Borrower to repay any portion of the Obligations or a
material impairment in the value or priority of Lender's security interest in the Collateral.

"Obligations" are Borrower's obligation to pay when due any debts, principal, interest, Lender's Expenses, Prepayment Fee, Final Payment,
and other amounts Borrower owes Lender now or later, whether under this Agreement, the Loan Documents, or otherwise, including, without limitation, all obligations relating to letters of credit
(including reimbursement obligations for drawn and undrawn letters of credit), cash management services, and foreign exchange contracts, if any, and including interest accruing after Insolvency
Proceedings begin (whether or not allowed) and debts, liabilities, or obligations of Borrower assigned to Lenders, and the performance of Borrower's duties under the Loan Documents. Notwithstanding
anything to the contrary contained herein, the term "Obligations" shall not include any obligations of Borrower under the Warrant or any equity-related documents executed solely in connection
therewith.

"Operating Documents"are, for any Person, such Person's formation documents, as certified with the Secretary of State of such Person's
state of formation on a date that is no earlier than 30 days prior to the Effective Date, and (a) if such Person is a corporation, its bylaws in current form, (b) if such Person
is a limited liability company, its limited liability company agreement (or similar agreement), and (c) if such Person is a partnership, its partnership agreement (or similar agreement), each
of the foregoing with all current amendments or modifications thereto.

"Payment/Advance Form" is that certain form attached hereto asExhibit B.

"Payment Date" is the first Business Day of each calendar month.

"Perfection Certificate" is defined in Section 5.1.

"Permitted Indebtedness" is:



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"Permitted Investments" are:



"Permitted Liens" are:



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

"Prepayment Fee" shall be an additional fee payable to the Lender in amount equal to:



"Registered Organization" is any "registered organization" as defined in the Code with such additions to such term as may hereafter be
made

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"Requirement of Law" is as to any Person, the organizational or governing documents of such Person, and any law (statutory or common),
treaty, rule or regulation or determination of an arbitrator or a court or other Governmental Authority, in each case applicable to or binding upon such Person or any of its property or to which such
Person or any of its property is subject.

"Responsible Officer" is any of the Chief Executive Officer, President, Chief Financial Officer and Controller of Borrower.

"Secured Promissory Note"is defined in Section 2.3.

"Secured Promissory Note Record"A record maintained by Lender with respect to the outstanding Obligations and credits made thereto.

"Securities Account" is any "securities account" as defined in the Code with such additions to such term as may hereafter be made.

"Subordinated Debt" is indebtedness incurred by Borrower subordinated to all of Borrower's now or hereafter indebtedness to Lender
(pursuant to a subordination, intercreditor, or other similar agreement in form and substance satisfactory to Lender and entered into between Lender, the Borrower and the other creditor), on terms
acceptable to Lender.

"Subsidiary" means, with respect to any Person, any Person of which more than 50.0% of the voting stock or other equity interests (in the
case of Persons other than corporations) is owned or controlled, directly or indirectly, by such Person or one or more of Affiliates of such Person.

"Term Loan"is defined in Section 2.1.1 hereof.

"Term Loan Maturity Date" is the last Payment Date for each Term Loan.

"Transfer" is defined in Section 7.1.

"Warrant" is that certain Warrant to Purchase Stock dated as of the Effective Date executed by Borrower in favor of Lender.

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IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be executed as a sealed instrument under the laws of the Commonwealth
of Virginia as of the Effective Date.

|BORROWER:                    |  | 
|---------------------------- |  | 
|METABASIS THERAPEUTICS, INC. |  | 
|By                           |  | 
|                             |  | 
|Name:                        |  | 
|                             |  | 
|Title:                       |  | 
|                             |  | 
|ARAMED, INC.                 |  | 
|By                           |  | 
|                             |  | 
|Name:                        |  | 
|                             |  | 
|Title:                       |  | 
|                             |  | 
|LENDER:                      |  | 
|OXFORD FINANCE CORPORATION   |  | 
|By                           |  | 
|                             |  | 
|Name:                        |  | 
|                             |  | 
|Title:                       |  | 
|                             |  | 

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EXHIBIT A

The
Collateral consists of all of Borrower's right, title and interest in and to the following personal property:

All
goods, Accounts (including health-care receivables), Equipment, Inventory, contract rights or rights to payment of money, leases, license agreements, franchise
agreements, General Intangibles (except as provided below), commercial tort claims, documents, instruments (including any promissory notes), chattel paper (whether tangible or electronic), cash,
deposit accounts, all certificates of deposit, fixtures, letters of credit rights (whether or not the letter of credit is evidenced by a writing), securities, and all other investment property,
supporting obligations, and financial assets, whether now owned or hereafter acquired, wherever located; and

all
Borrower's Books relating to the foregoing, and any and all claims, rights and interests in any of the above and all substitutions for, additions, attachments, accessories,
accessions and improvements to and replacements, products, proceeds and insurance proceeds of any or all of the foregoing.

Notwithstanding
the foregoing, the Collateral does not include any of the following, whether now owned or hereafter acquired: (i) any interest in a foreign subsidiary to the
extent such interest exceeds 65% of the total outstanding voting interests in such foreign subsidiary, or (ii) any copyright rights, copyright applications, copyright registrations and like
protections in each work of authorship and derivative work, whether published or unpublished, any patents, patent applications and like protections, including improvements, divisions, continuations,
renewals, reissues, extensions, and continuations-in-part of the same, trademarks, service marks and, to the extent permitted under applicable law, any applications therefor,
whether registered or not, and the goodwill of the business of Borrower connected with and symbolized thereby, know-how, operating manuals, trade secret rights, rights to unpatented
inventions, and any claims for damage by way of any past, present, or future infringement of any of the foregoing; provided, however, the Collateral shall include all Accounts, license and royalty
fees and other revenues, proceeds, or income arising out of or relating to any of the foregoing.

Pursuant
to the terms of a certain negative pledge arrangement with Lender, Borrower has agreed not to encumber any of its copyright rights, copyright applications, copyright
registrations and like
protections in each work of authorship and derivative work, whether published or unpublished, any patents, patent applications and like protections, including improvements, divisions, continuations,
renewals, reissues, extensions, and continuations-in-part of the same, trademarks, service marks and, to the extent permitted under applicable law, any applications therefor,
whether registered or not, and the goodwill of the business of Borrower connected with and symbolized thereby, know-how, operating manuals, trade secret rights, rights to unpatented
inventions, and any claims for damage by way of any past, present, or future infringement of any of the foregoing, without Lender's prior written consent.

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EXHIBIT B

Loan Payment/Advance Request Form

METABASIS THERAPEUTICS, INC.DEADLINE IS NOON E.S.T.*

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|Fax To: |  | Date: | 
|------- |  | ----- | 

LOAN PAYMENT:

|From Account #        | (Deposit Account #) |  | To Account #      | (Loan Account #)
|--------------------- | ------------------- |  | ----------------- | ----------------
|Principal $           |                     |  | and/or Interest $ |                 
|Authorized Signature: |                     |  | Phone Number:     |                 
|Print Name/Title:     |                     |  |                   |                 

LOAN ADVANCE:

CompleteOutgoing Wire Requestsection below if all or a portion of the funds from this loan advance are for an outgoing wire.

|From Account #                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | (Loan Account #) |  | To Account #  | (Deposit Account #)
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------------- |  | ------------- | -------------------
|Amount of Advance $                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |                  |  |               |                    
|All Borrower's representations and warranties in the Loan and Security Agreement are true, correct and complete in all material respects on the date of the request for an advance; provided, however, that such materiality qualifier shall not be
applicable to any representations and warranties that already are qualified or modified by materiality in the text thereof; and provided, further that those representations and warranties expressly referring to a specific date shall be true, accurate
and complete in all material respects as of such date:
|Authorized Signature:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |                  |  | Phone Number: |                    
|Print Name/Title:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |                  |  |               |                    

OUTGOING WIRE REQUEST:
Complete only if all or a portion of funds from the loan advance above is to be wired.Deadline for same day processing is noon, E.S.T.

|Beneficiary Name:   |  |  | Amount of Wire: $ | 
|------------------- |  |  | ----------------- | 
|Beneficiary Lender: |  |  | Account Number:   | 
|City and State:     |  |  |                   | 

|
|

|Beneficiary Lender Transit (ABA) #: |  |  | Beneficiary Lender Code (Swift, Sort, Chip, etc.): (For International Wire Only) | 
|----------------------------------- |  |  | -------------------------------------------------------------------------------- | 

|
|

|Intermediary Lender:                                                                                                                                                                                                                                                                                       |  |  | Transit (ABA) #:             | 
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |  |  | ---------------------------- | 
|For Further Credit to:                                                                                                                                                                                                                                                                                     | 
|Special Instruction:                                                                                                                                                                                                                                                                                       | 
|By signing below, I (we) acknowledge and agree that my (our) funds transfer request shall be processed in accordance with and subject to the terms and conditions set forth in the agreements(s) covering
funds transfer service(s), which agreements(s) were previously received and executed by me (us).
|Authorized Signature:                                                                                                                                                                                                                                                                                      |  |  | 2nd Signature (if required): | 
|Print Name/Title:                                                                                                                                                                                                                                                                                          |  |  | Print Name/Title:            | 
|Telephone #:                                                                                                                                                                                                                                                                                               |  |  | Telephone #:                 | 

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EXHIBIT C
COMPLIANCE CERTIFICATE

|TO:   | OXFORD FINANCE CORPORATION, as Lender |  | Date: | 
|----- | ------------------------------------- |  | ----- | 
|FROM: | METABASIS THERAPEUTICS, INC.          |  |       | 

The
undersigned authorized officer of Metabasis Therapeutics, Inc. ("Borrower") certifies that under the terms and conditions of the Loan and Security Agreement between Borrower,
and the Lender (the "Agreement"), (1) there are no Events of Default which have occurred and are continuing, (2) all representations and warranties in the Agreement are true and correct
in all material respects on this date except as noted below; provided, however, that such materiality qualifier shall not be applicable to any representations and warranties that already are qualified
or modified by materiality in the text thereof; and provided, further that those representations and warranties expressly referring to a specific date shall be true, accurate and complete in all
material respects as of such date, (3) Borrower, and each of its Subsidiaries, has timely filed all required tax returns and reports, and Borrower has timely paid all foreign, federal, state
and local taxes, assessments, deposits and contributions owed by Borrower except as otherwise permitted pursuant to the terms of Section 5.8 of the Agreement, and (4) no Liens have been
levied or claims made against Borrower or any of its Subsidiaries relating to unpaid employee payroll or benefits of which Borrower has not previously provided written notification to Lender. Attached
are the required documents supporting the certification. The undersigned certifies, in the capacity as an officer of the Borrower, that these are prepared in accordance with GAAP consistently applied
from one period to the next except as explained in an accompanying letter or footnotes or as permitted in the Agreement. The undersigned acknowledges, in the capacity as an officer of the Borrower,
that no borrowings may be requested at any time or date of determination that Borrower is not in compliance with any of the terms of the Agreement, and that compliance is determined not just at the
date this certificate is delivered. Capitalized terms used but not otherwise defined herein shall have the meanings given them in the Agreement.

Please indicate compliance status by circling Yes/No under "Complies" column.

|Reporting Covenant     |  | Required                 |  | Complies 
|---------------------- |  | ------------------------ |  | ---------
|Compliance Certificate |  | Quarterly within 45 days |  | Yes    No

The
following are the exceptions with respect to the certification above: (If no exceptions exist, state "No exceptions to note.")

|
|
|
|

|
|

|                             |  |  | LENDER USE ONLY                
|---------------------------- |  |  | -------------------------------
|METABASIS THERAPEUTICS, INC. |  |  |                                
|By:                          |  |  | Received by:                   
|Name:                        |  |  |                                
|Title:                       |  |  | Date:                          
|                             |  |  | Verified:                      
|                             |  |  |                                
|                             |  |  | Date:                          
|                             |  |  | Compliance Status:    Yes    No

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EXHIBIT D

SECURED PROMISSORY NOTE

|$ |  |  | Dated:
, 2008
|- |  |  | -------------

FOR
VALUE RECEIVED, the undersigned, METABASIS THERAPEUTICS, INC., a Delaware corporation and ARAMED, INC..,
a                        corporation (jointly and severally,
individually and collectively, the "Borrower"), HEREBY PROMISES TO PAY to the order of OXFORD FINANCE CORPORATION
("Lender") the principal amount of Five Million Dollars ($5,000,000) or such lesser amount as shall equal the outstanding principal balance of the Term
Loan made to Borrower by Lender, plus interest on the aggregate unpaid principal amount of Term Loan, at the rates and in accordance with the terms of the Loan and Security Agreement by and between
Borrower and Lender (as amended, restated, supplemented or otherwise modified from time to time, the "Loan Agreement"). If not sooner paid, the entire principal amount and all accrued interest
hereunder and under the Loan Agreement shall be due and payable on Term Loan Maturity Date as set forth in the Loan Agreement.

Borrower
agrees to pay any initial partial month interest payment from the date of this Note to the first Payment Date ("Interim Interest") on the first Payment Date.

Principal,
interest and all other amounts due with respect to the Term Loan, are payable in lawful money of the United States of America to Lender as set forth in the Loan Agreement and
this Secured Promissory Note. The principal amount of this Note and the interest rate applicable thereto, and all payments made with respect thereto, shall be recorded by Lender and, prior to any
transfer hereof, endorsed on the grid attached hereto which is part of this Note.

The
Loan Agreement, among other things, (a) provides for the making of a secured Term Loan to Borrower, and (b) contains provisions for acceleration of the maturity hereof
upon the happening of certain stated events.

This
Note may not be prepaid except as set forth inSection 2.1.1(d) and Section 2.1.1(e)of the Loan Agreement.

This
Note and the obligation of Borrower to repay the unpaid principal amount of the Term Loan, interest on the Term Loan and all other amounts due Lender under the Loan Agreement is
secured under the Loan Agreement.

Presentment
for payment, demand, notice of protest and all other demands and notices of any kind in connection with the execution, delivery, performance and enforcement of this Note are
hereby waived.

Borrower
shall pay all reasonable fees and expenses, including, without limitation, reasonable attorneys' fees and costs, incurred by Lender in the enforcement or attempt to enforce any
of Borrower's obligations hereunder not performed when due. This Note shall be governed by, and construed and interpreted in accordance with, the laws of the Commonwealth of Virginia.

Note Register; Ownership of Note.The ownership of an interest in this Note shall be registered on a record of ownership
maintained by Lender or its agent. Notwithstanding anything else in this Note to the contrary, the right to the principal of, and stated interest on, this Note may be transferred only if the transfer
is registered on such record of ownership and the transferee is identified as the owner of an interest in the obligation. Borrower shall be entitled to treat the registered holder of this Note (as
recorded on such record of ownership) as the owner in fact thereof for all purposes and shall not be bound to recognize any equitable or other claim to or interest in this Note on the part of any
other person or entity.

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IN
WITNESS WHEREOF, Borrower has caused this Note to be duly executed by one of its officers thereunto duly authorized on the date hereof.

| |  | BORROWER:                   
| |  | ----------------------------
| |  | METABASIS THERAPEUTICS, INC.
| |  | By:                         
| |  |                             
| |  | Name:                       
| |  |                             
| |  | Title:                      
| |  |                             
| |  | ARAMED, INC.                
| |  | By:                         
| |  |                             
| |  | Name:                       
| |  |                             
| |  | Title:                      
| |  |                             

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