Exhibit 10.13

SEVENTH AMENDMENT

THIS SEVENTH AMENDMENT (this “Amendment”) is made and entered into as of July 15, 2010, by and between NORTHERN CALIFORNIA INDUSTRIAL PORTFOLIO, INC., a Maryland corporation (“Landlord”), and METABOLEX, INC., a Delaware corporation (“Tenant”).

RECITALS

NOW, THEREFORE, in consideration of the mutual covenants and agreements herein contained and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, Landlord and Tenant agree as follows:

For 3876 Bay Center Place:

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For 3880 Bay Center Place:

All such monthly Base Rent and annual Base Rent shall be payable by Tenant in accordance with the terms of the Lease, as amended hereby.

Notwithstanding anything in the Lease to the contrary, so long as Tenant is not in default under the Lease, Tenant shall be entitled to an abatement of monthly Base Rent with respect to the Premises, as originally described in the Lease, in the amount of $16,812.22 per month for the full calendar months of July, 2010, through November, 2010, inclusive. The maximum total amount of monthly Base Rent abated with respect to the Premises in accordance with the foregoing shall equal $84,061.10 (the “Abated Monthly Base Rent”). If Tenant defaults under the Lease at any time during the Term and fails to cure such default within any applicable cure period under the Lease, then all Abated Monthly Base Rent shall immediately become due and payable. Only monthly Base Rent shall be abated pursuant to this Section, as more particularly described herein, and, and all other rent and other costs and charges specified in the Lease shall remain as due and payable pursuant to the provisions of the Lease.

Additional Security Deposit. No additional Security Deposit shall be required in connection with this Amendment.

Basic Operating Costs. For the period commencing on the Extension Date and ending on the Extended Termination Date, Tenant shall pay for all additional rent payable under the Lease, including Tenant’s Proportionate Share of Basic Operating Costs, in accordance with the terms of the Lease.

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“Northern California Industrial Portfolio, Inc.

c/o RREEF

2185 North California Boulevard, Suite 285

Walnut Creek, California 94596

Attn: Asset Manager”

“Northern California Industrial Portfolio, Inc., DBA Port of Oakland Business Center,

Dept. 2061

P.O. Box 39000

San Francisco, California 94139”

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“B. Tenant’s Insurance. Tenant shall keep in force throughout the Term: (a) a Commercial General Liability insurance policy or policies to protect the Landlord, Landlord’s investment manager, and the trustees, boards of directors, officers, general partners, beneficiaries, stockholders, employees and agents of each of them (individually, a “Landlord Party” and collectively, the “Landlord Parties”) against any liability to the

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public or to any invitee of Tenant or a Landlord Party incidental to the use of or resulting from any accident occurring in or upon the Premises with a limit of not less than $2,000,000 in the annual aggregate, or such larger amount as Landlord may prudently require from time to time, covering bodily injury and property damage liability and $1,000,000 products/completed operations aggregate; (b) Business Auto Liability covering owned, non-owned and hired vehicles with a limit of not less than $1,000,000 per accident; (c) Worker’s Compensation Insurance with limits as required by statute and Employers Liability with limits of $1,000,000 each accident, $1,000,000 disease policy limit, $1,000,000 disease-each employee; (d) All Risk or Special Form coverage protecting Tenant against loss of or damage to Tenant’s alterations, additions, improvements, carpeting, floor coverings, panelings, decorations, fixtures, inventory and other business personal property situated in or about the Premises to the full replacement value of the property so insured; and, (e) Business Interruption Insurance with limit of liability representing loss of at least approximately six (6) months of income.

The aforesaid policies shall (a) be provided at Tenant’s expense; (b) name the Landlord Parties as additional insureds (General Liability) and loss payee (Property—Special Form); (c) be issued by an insurance company with a minimum Best’s rating of “A-:VII” during the Term; and (d) provide that said insurance shall not be canceled unless thirty (30) days prior written notice (ten days for non-payment of premium) shall have been given to Landlord; a certificate of Liability insurance on ACORD Form 25 and a certificate of Property insurance on ACORD Form 28 shall be delivered to Landlord by Tenant at least thirty (30) days prior to each renewal of said insurance.

Whenever Tenant shall undertake any alterations, additions or improvements in, to or about the Premises (“Work”) the aforesaid insurance protection must extend to and include injuries to persons and damage to property arising in connection with such Work, without limitation including liability under any applicable structural work act, and such other insurance as Landlord shall require; and the policies of or certificates evidencing such insurance must be delivered to Landlord prior to the commencement of any such Work.

C. Indemnification. None of the Landlord Parties shall be liable and Tenant hereby waives all claims against them for any damage to any property or any injury to any person in or about the Premises or the Building by or from any cause whatsoever (including without limiting the foregoing, rain or water leakage of any character from the roof, windows, walls, basement, pipes, plumbing works or appliances, the Building not being in good condition or repair, gas, fire, oil, electricity or theft), except to the extent caused by or arising from the active negligence or willful misconduct of Landlord or its agents, employees or contractors. Tenant shall protect, indemnify and hold the Landlord Parties harmless from and against any and all loss, claims, liability or costs (including court costs and attorney’s fees) incurred by reason of (a) any damage to any property (including but not limited to property of any Landlord Party) or any injury (including but not limited to death) to any person occurring in, on or about the Premises or the Building to the extent that such injury or damage shall be caused by or arise from any actual or alleged act, neglect, fault, or omission by or of Tenant or Tenant’s Parties to meet any standards imposed by any duty with respect to the injury or damage; (b) the conduct or management of any work or thing whatsoever done by the Tenant in or about the Premises or from transactions of the Tenant concerning the Premises; (c) Tenant’s actual or asserted failure to comply with any and all Regulations applicable to the condition or use of the Premises or

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its occupancy; or (d) any breach or default on the part of Tenant in the performance of any covenant or agreement on the part of the Tenant to be performed pursuant to the Lease. The provisions of this Paragraph shall survive the termination of the Lease with respect to any claims or liability accruing prior to such termination.”

Tenant shall provide Landlord with a certificate of insurance evidencing Tenant’s insurance, including without limitation, the insurance set forth in this Section 6.9, upon delivery of this Amendment, executed by Tenant, to Landlord, and thereafter as necessary to assure that Landlord always has current certificates evidencing Tenant’s insurance.”

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IN WITNESS WHEREOF, Landlord and Tenant have entered into and executed this Amendment as of the date first written above.

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EXHIBIT A – HAZARDOUS MATERIALS QUESTIONNAIRE

attached to and made a part of the Amendment bearing the date of Error! Reference source not found., between NORTHERN CALIFORNIA INDUSTRIAL PORTFOLIO, INC., a Maryland corporation, as Landlord, and METABOLEX, INC., a Delaware corporation, as Tenant

This questionnaire is designed to solicit information regarding Tenant’s proposed use, generation, treatment, storage, transfer or disposal of hazardous or toxic materials, substances or wastes. If this questionnaire is attached to or provided in connection with a lease, the reference herein to any such items shall include all items defined as “Hazardous Materials,” “Hazardous Substances,” “Hazardous Wastes,” “Toxic Materials,” “Toxic Substances, “Toxic Wastes,” or such similar definitions contained in such lease. Please complete the questionnaire and return it to Landlord for evaluation. If your use of materials or substances, or generation of wastes is considered to be significant, further information may be requested regarding your plans for hazardous and toxic materials management. Submission to Landlord of this Hazardous Materials Questionnaire or Landlord’s request for additional information shall not deemed consent by Landlord to Tenant’s use of the materials disclosed herein. Your cooperation in this matter is appreciated. If you have any questions, do not hesitate to call us for assistance.

Name (Corporation, Individual, Corporate or Individual DBA, or Public Agency): Metabolex, Inc.

Standard Industrial Classification Code (SIC): 8731

Dates and Descriptions of Significant Additions, Alterations or Improvements: 2000 Medicinal Chemistry lab buildout, 2001 office expansion, 2007 lab and office remodel

Proposed Additions, Alterations or Improvements, if any: N/A at this time N/A

Describe proposed use and operation of Premises including (i) services to be performed, (ii) nature and types of manufacturing or assembly processes, if any, and (iii) the materials or products to be stored at the Premises.

Research Lab developing therapeutics for diabetes and other metabolic disorders, activities include: Biological Research, Medicinal Chemistry, In-vivo Pharmacology (rats/mice), research supplies and reagents

Will the operation of your business at the Premises involve the use, generation, treatment, storage, transfer or disposal of hazardous wastes or materials? Do they now? Yes X No      If the answer is “yes,” or if your SIC code number is between 2000 to 4000, please complete Section 5.

Does or will the operation of any facet of your business at the Premises require any permits, licenses or plan approvals from any of the following agencies?

If the answer to any of the above is “yes,” please indicate permit or license numbers, issuing agency and expiration date or renewal date, if applicable.

Hayward Industrial Wastewater discharge Permit 96-1122.01-2MS exp 8/19/12, California Radioactive Material License 5511-01, under timely renewal. California DTSC, CAL000094498, Hayward Fire CUPA HMBP 10-0112201-010951, DEA RMO185620

If your answer to any of the above is “yes,” please complete Sections 6 and 7.

Will any hazardous or toxic materials or substances be stored on the Premises? Yes X No      If the answer is “yes,” please describe the materials or substances to be stored, the quantities thereof and the proposed method of storage of the same (i.e., drums, aboveground or underground storage tanks, cylinders, other), and whether the material is a Solid (S), Liquid (L) or Gas (G):

Attach additional sheets if necessary.

Is any modification of the Premises improvements required or planned to mitigate the release of toxic or hazardous materials substance or wastes into the environment? Yes      No X If the answer is “yes,” please describe the proposed Premises modifications:

Will any hazardous waste, including recyclable waste, be generated by the operation of your business at the Premises? Yes X No      If the answer is “yes,” please list the hazardous waste which is expected to be generated (or potentially will be generated) at the Premises, its hazard class and volume/frequency of generation on a monthly basis.

Attach additional sheets if necessary.

If the answer is “yes,” please also indicate if any such wastes are to be stored within the Premises and the proposed method of storage (i.e., drums, aboveground or underground storage tanks, cylinders, other).

Attach additional sheets if necessary.

If the answer is “yes,” please also describe the method(s) of disposal for each waste. Indicate where disposal will take place including the methods, equipment and companies to be used to transport the waste:

Ingenium will remove transport and dispose or recycle all, solid and liquid chemical waste as well as Universal Waste Environmental Management Controls, will remove transport and dispose of all low level radioactive waste

Is any treatment or processing of hazardous wastes to be conducted at the Premises? Yes      No X If the answer is “yes,” please describe proposed treatment/processing methods:

Which agencies are responsible for monitoring and evaluating compliance with respect to the storage and disposal of hazardous materials or wastes at or from the Premises? (Please list all agencies):

Hayward Fire Department. California Radiologic Health Branch, Hayward Water Polution Source Control, California Department of Toxic Substance Control

Have there been any agency enforcement actions regarding Tenant (or any affiliate thereof), or any existing Tenant’s (or any affiliate’s) facilities, or any past, pending or outstanding administrative orders or consent decrees with respect to Tenant or any affiliate thereof? Yes      No X If the answer is “yes,” have there been any continuing compliance obligations imposed on Tenant or its affiliates as a result of the decrees or orders? Yes      No      If the answer is “yes,” please describe:

Has Tenant or any of its affiliates been the recipient of requests for information, notice and demand letters, cleanup and abatement orders, or cease and desist orders or other administrative inquiries? Yes      No X If the answer is “yes,” please describe:

Are there any pending citizen lawsuits, or have any notices of violations been provided to Tenant or its affiliates or with respect to any existing facilities pursuant to the citizens suit provisions of any statute? Yes      No X If the answer is “yes,” please describe:

Have there been any previous lawsuits against the company regarding environmental concerns? Yes      No X If the answer is “yes,” please describe how these lawsuits were resolved:

Has an environmental audit ever been conducted at any of your company’s existing facilities? Yes X No      If the answer is “yes,” please describe:

We have conducted outside audits of our Safety Programs by Hazard Solutions. LLC We have also been subject to inspection by a RREI contractor on an annual basis.

Does your company carry environmental impairment insurance? Yes      No X If the answer is “yes,” what is the name of the carrier and what are the effective periods and monetary limits of such coverage?

Is (or will there be) any electrical transformer or other equipment containing polychlorinated biphenyls located at the Premises?

Yes      No X If the answer is “yes,” please specify the size, number and location (or proposed location):

Is (or will there be) any tank for storage of a petroleum product located at the Premises? Yes X No      If the answer is “yes,” please specify capacity and contents of tank; permits, licenses and/or approvals received or to be received therefor and any spill prevention control or conformance plan to be taken in connection therewith:

175 gallon belly tank on diesel generator - Spill kits/drums on hand, in house 40Hr HAZWOPER trained spill response team, Safe Compliance Management and Hazard Solutions, LLC and Ingenium identified to provide additional resources as needed as well as lo emergency response personnel.

Has any hazardous material, substance or waste spilled, leaked, discharged, leached, escaped or otherwise been released into the environment at the Premises? Yes      No X If the answer is “yes,” please describe including (i) the date and duration of each such release, (ii) the material, substance or waste released, (iii) the extent of the spread of such release into or onto the air, soil and/or water, (iv) any action to clean up the release, (v) any reports or notifications made of filed with any federal, state, or local agency, or any quasi-governmental agency (please provide copies of such reports or notifications) and (vi) describe any legal, administrative or other action taken by any of the foregoing agencies or by any other person as a result of the release:

This Hazardous Materials Questionnaire is certified as being true and accurate and has been completed by the party whose signature appears below on behalf of Tenant as of the date set forth below.