LICENSE AGREEMENT

Exhibit 99.1

Confidential Treatment Requested

Under 17 C.F.R. Sections 200.80(b)(4) and 240.24b-2.

Omitted Portions Filed Separately with

the Securities Exchange Commission

LICENSE AGREEMENT

License Agreement (this “ Agreement ”) dated as of November 30, 2006, between ACADIA Pharmaceuticals Inc., a Delaware corporation, with offices located at 3911 Sorrento Valley Boulevard, San Diego, CA 92121, USA (“ ACADIA ”), and Société de Conseils, de Recherches et d’Applications Scientifiques SAS, a French corporation member of the IPSEN GROUP with offices located at 42 rue du Docteur Blanche, 75016 Paris, FRANCE (“ IPSEN ”).

WHEREAS, ACADIA is developing and commercializing certain compounds or pharmaceutical products;

WHEREAS, IPSEN owns or controls certain patents and patent applications, relating to the Licensed Product (as defined below); and

WHEREAS, IPSEN desires to grant, and ACADIA desires to be granted, a non-exclusive license in the Territory (as defined below) to such patents and patent applications, to pursue regulatory approval and commercialization of Licensed Product all on the terms and conditions as set forth herein below.

NOW, THEREFORE, in consideration of the mutual covenants and agreements provided herein, ACADIA and IPSEN hereby agree as follows:

For purposes of this Agreement, the following definitions shall be applicable:

1.1 “Acadia Patent Rights” means the Patents and Patent Applications listed in Exhibit A here attached (including any Patents issuing from such Patent Applications).

1.2 “Affiliate” means, with respect to a party to this Agreement, any entity directly or indirectly controlled by, controlling, or under common control with, such party to this Agreement, but only for so long as such control shall continue. For purposes of this definition, “control” (including, with correlative meanings, “controlled by”, “controlling” and “under common control with”) of an entity means possession, direct or indirect, of (i) the power to direct or cause direction of the management and policies of such entity (whether through ownership of securities or partnership or other ownership interests, by contract or otherwise), or (ii) at least fifty percent (50)% of the outstanding voting securities (whether directly owned or issuable pursuant to any option, warrant or other similar arrangement) or other comparable equity interests of such entity.

1.3 “Commercial Sale” means the sale of Licensed Product whether by ACADIA, ACADIA’s Affiliates or Sublicensees to a third party and shall exclude (i) any transfer of Licensed Product by ACADIA to its Affiliates or Sublicensees and (ii) any distribution of Licensed Product for use in Development Activities or as samples.

1.4 “Compound” means any of the […***…] compounds, […***…], listed in Exhibit C here attached. Such list may be amended by ACADIA from time to time subject to prior notice to IPSEN and provided that (i) such new compounds are […***…] and (ii) such list as amended contains […***…] compounds.

1.5 “Development Activities” shall mean any research, development, manufacturing or registration activities relating to the Compounds and/or the Licensed Products.

1.6 “Effective Date” shall mean the date set forth in the opening paragraph of this Agreement.

1.7 “FDA” shall mean the Food and Drug Administration of the United States of America.

1.8 “Field” means all human uses […***…]. For the sake of clarity, conditions that can cause or otherwise be associated with […***…] shall remain included in the Field. For example, […***…]. For the avoidance of doubt, the Field shall not include the following […***…].

1.9 “Ipsen Patent Rights” means the Patents and Patent Applications listed in Exhibit B here attached (including any Patents issuing from such Patent Applications).

1.10 “Issued Valid Claim” means any claim from an issued and unexpired Patent under the Ipsen Patent Rights, which covers a Licensed Product and but for this License Agreement ACADIA could not make, have made, develop, use, sell, offer for sale, commercially exploit, or import the Licensed Product without said license, and which has not been abandoned, revoked or held unenforceable or invalid by a decision of a court or other governmental authority of competent jurisdiction, and which has not been disclaimed, denied or admitted to be invalid or unenforceable through reissue or disclaimer or otherwise.

1.11 “Licensed Product” means any product containing one or more Compounds as an active ingredient.

1.12 “Major Countries” means the […***…].

1.13 “Net Sales” means with respect to any Licensed Product, gross sales of ACADIA, its Affiliates and Sublicensees (each, a “ Selling Party ”) of such Licensed Product to unaffiliated third

parties, less (i) actual bad debts related to such Licensed Product, (ii) credits for sales returns and allowances actually paid, granted or accrued, (iii) trade, quantity and cash discounts and any other adjustments actually allowed and taken with respect to such invoiced amounts, including, but not limited to, granted on account of price adjustments, billing errors, rejected goods, damaged or defective goods, recalls, returns, rebates, chargeback rebates, reimbursements or similar payments granted or given to wholesalers or other distributors, buying groups, health care insurance carriers or other institutions, adjustments arising from consumer discount programs, (iv) customs or excise duties, sales tax, consumption tax, value added tax, and other taxes (except income taxes) or duties relating to sales, (v) any payment in respect of sales to any government, or to any Regulatory Authority, or with respect to any government-subsidized program or managed care organization, and (vi) freight and insurance, in each case as determined from books and records of the Selling Party maintained in accordance with generally acceptable accounting principles in the United States of America, consistently applied. For the avoidance of doubt, Net Sales shall not include any distribution of Licensed Product for use in Development Activities or as samples and shall not include sales by ACADIA to its Affiliates and Sublicensees for resale, provided that if ACADIA sells a Licensed Product to an Affiliate or to a Sublicensee for resale, Net Sales shall include the amounts invoiced by such Affiliate or Sublicensee to non-Affiliate third parties on the resale of such Licensed Product.

1.14 “Other Countries” means any country of the Territory other than the Major Countries.

1.15 “Patents” means any issued and unexpired patents, certificates of invention, and any supplemental protection certificates together with any issued and unexpired extensions, registrations, confirmations, reissues, substitutions, requests for continued examination, term restorations, divisions, continuations or continuations-in-part, reexamination or renewals thereof. “Patents” shall include any patent or Patent issuing upon any Patent Application

1.16 “Patent Applications” means any patent applications, provisional applications, or applications for certificates of invention, which have not become Patents.

1.17 “Pending Valid Claim” any claim from a Patent Application under the Ipsen Patent Rights, which covers a Licensed Product and but for this License Agreement ACADIA could not make, have made, develop, use, sell, offer for sale, commercially exploit, or import the Licensed Product without said license, and which has not been abandoned, revoked or held unenforceable or invalid by a decision of a court or other governmental authority of competent jurisdiction, and which has not been disclaimed, denied or admitted to be invalid or unenforceable through reissue or disclaimer or otherwise.

1.18 “Phase III Clinical Trial” means a clinical trial that […***…].

1.19 “Regulatory Application” means all regulatory applications submitted to a Regulatory Authority for Regulatory Approval (together with supporting documentation).

1.20 “Regulatory Approval” means all approvals, licenses, registrations or authorizations necessary for the marketing, sale and/or use of a Licensed Product in a particular jurisdiction including any pricing or reimbursement approval.

1.21 “Regulatory Authority” means any national, supra-national (e.g., the FDA, the European Commission, the Council of the European Union, or the European Medicines Agency (“EMEA”)), regional, state or local regulatory agency, department, bureau, commission, council or other governmental entity in any jurisdiction of the Territory involved in the granting of Regulatory Approval for pharmaceutical products.

1.22 “Royalty Payments” shall have the meaning ascribed to it in Section 4.5 of this Agreement.

1.23 “Sublicensee” means any third party (other than an ACADIA Affiliate) to whom ACADIA or an ACADIA Affiliate has granted the right, directly or indirectly, to research, develop, make and/or sell any Licensed Product, provided that Sublicensee shall exclude wholesalers and resellers of Licensed Product, which do not engage in any marketing or promotion of the Licensed Product.

1.24 “Term” have the meaning ascribed to it in Section 9 of this Agreement.

1.25 “Territory” means all countries of the world.

2.1 Non-Exclusive License . Subject to the terms and conditions of this Agreement, IPSEN hereby grants to ACADIA and its Affiliates, and ACADIA hereby accepts, a non-exclusive license, with the right to grant and authorize sublicenses, under the Ipsen Patent Rights to research, develop, have developed, make, have made, use, sell, offer for sale, commercially exploit, and import the Licensed Products in the Field in the Territory.

2.2 Sublicenses . ACADIA shall have the right to appoint Sublicensees. Immediately upon execution of any sublicense agreement, ACADIA shall provide to IPSEN the terms and conditions of the executed agreement with such Sublicensee including all financial terms for the purpose of the implementation of Section 4.4 of this Agreement. ACADIA shall ensure that all of the applicable terms and conditions of this Agreement shall apply to the Sublicensee to the same extent as they apply to ACADIA hereunder for all purposes. ACADIA assumes full responsibility for the performance of all obligations so imposed on such Sublicensee and will itself account to IPSEN for all payments due under this Agreement by reason of such sublicense.

2.3 Retained Rights . Except as otherwise provided in this Agreement, IPSEN and its Affiliates retain the right to use the Ipsen Patent Rights for any purpose whatsoever.

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3.1 Reporting . ACADIA shall, in a timely manner, notify IPSEN of major events in the development of the Compounds or Licensed Products (including without limitation the occurrence of the events triggering the Milestone Payments as provided for in Section 4.2 of this Agreement) and shall provide to IPSEN within sixty (60) days after the end of each calendar year, annual status reports summarizing the Development Activities conducted during the past calendar year for each Compound or Licensed Product.

3.2 Diligence . In the event ACADIA is not conducting any Development Activities with respect to the Compounds or the Licensed Products for a period of more than three (3) years, Ipsen shall have the option to terminate this Agreement by notifying ACADIA its intention to do so pursuant to this Section 3.2. In the event (i) ACADIA fails to resume Development Activities within sixty (60) days as from receipt of Ipsen’s notification and (ii) ACADIA fails to notify Ipsen of its commitment to resume Development Activities in the sixty (60) days following receipt of such Ipsen notice, this Agreement shall automatically terminate without further notification upon expiry of the sixty-day period following delivery of the Ipsen notice.

4.1 Upfront Payment . ACADIA shall pay to IPSEN Two Hundred and Fifty Thousand (250,000) US Dollars within thirty (30) days following the Effective Date. Such payment shall be non-refundable and non-creditable.

4.2 Milestone Payments . ACADIA shall make the following creditable (pursuant to Section 4.4), non-refundable milestone payments to IPSEN within thirty (30) days following the occurrence of the following events (the “ Milestone Payments ”):

(a) […***…] US Dollars upon […***…];

(b) […***…] US Dollars upon […***…];

(c) […***…] US Dollars upon […***…].

For clarity, ACADIA shall make the foregoing Milestone Payments only once for the first Licensed Product to reach that stage.

4.3 Acquisition Fee . In the event of a Change-of-Control (as defined below), ACADIA, or the new entity resulting from the Change-of-Control, shall have an option to assume ACADIA’s rights and obligations under this Agreement by paying to IPSEN, within thirty (30) days as from the effective date of the Change-of-Control, a one-time only payment of […***…] US Dollars (the “ Acquisition Fee ”). Such Acquisition Fee shall be non-refundable and non-creditable. ACADIA, or the new entity resulting from the Change-of-Control, shall inform Ipsen by written notice of the occurrence of a Change-of-Control and shall notify Ipsen of the decision to exercise this option within thirty (30) days as from the effective date of Change-of-Control. In the event Ipsen does not receive a notice of intention to exercise the option within thirty (30) days as from the effective date of the Change-of-Control or evidence of payment of the Acquisition Fee within thirty (30) days as from the effective date of the Change-of-Control, ACADIA shall be deemed to have breached a material provision of this Agreement and Section 10.1(a) of this Agreement shall apply. The Acquisition Fee shall not be payable more than once.

For the purpose of this clause, “Change-of-Control” means:

(i) […***…];

(ii) a transaction (being either a direct or indirect transaction) which would result in:

(a) […***…], or

(b) a merger, reorganization or other business consolidation occurring in which ACADIA is not the surviving entity, or any reverse merger occurs in which ACADIA is the surviving entity, but which would result in either case in:

(1) […***…], or

(2) […***…],

(iii) […***…]; or

(iv) […***…].

In the event that (a) ACADIA assigns, delegates or sublicenses any rights under Section 2.1 of this Agreement to one or more of its Affiliates or (b) ACADIA sells, conveys, transfers, leases or disposes otherwise of all or substantially all of the assets of ACADIA including the Compounds and Licensed Products to one or more of its Affiliates, or (c) ACADIA sells, conveys, transfers, leases or disposes of the Compounds or Licensed Product business to one or more of its Affiliates, then Change-of-Control shall also mean any of the events described in (i) to (iv) above if they relate to such ACADIA Affiliate(s).

Notwithstanding the foregoing, a Change-of- Control shall be deemed to occur on account of the events described in (i) to (iv) only if the person(s) benefiting from such a Change-of-Control is a Competing Entity. For the purpose of this section, a Competing Entity shall mean a company that, at the time of the Change-of-Control, is researching or developing or markets a pharmaceutical product anywhere in the world.

4.4 Sublicensing Revenues . In the event ACADIA enters into an agreement with a Sublicensee in accordance with the provisions of Section 2.2 of this Agreement, ACADIA shall pay to IPSEN […***…] percent ([…***…]%) of any upfront payments (excluding the fair market value of equity sold, funding for the sole purpose of supporting identified and planned research and development works relating to the Compounds and/or the Licensed Products, transfer of goods and materials at cost plus an industry standard premium, and bona fide loans) or milestone payments (including without limitation milestone payments relating to research, development, regulatory or commercial events) received from any such Sublicensee (“ Ipsen Sublicense Share ”) within thirty (30) days following the receipt of such payments by ACADIA, provided that in no event will Ipsen Sublicense Share include any portion of sales for Licensed Products used to calculate royalties under Section 4.5 of this Agreement.

(a) any Milestone Payment already paid by ACADIA to IPSEN (if any) shall be deducted from any payments to be made by ACADIA to IPSEN with respect to an Ipsen Sublicense Share, provided, however, that (i) a Milestone Payment shall be deducted from an Ipsen Sublicense Share only once and (ii) if a Milestone Payment is credited only partially against a Ipsen Sublicense Share, the remaining non-credited amount of such Milestone Payment shall be creditable against future Ipsen Sublicense Share(s);

(b) any payment relating to an Ipsen Sublicense Share, after deduction of Milestone Payment as provided for in Section 4.4(a) above, shall be creditable against any Milestone Payments remaining to be paid under Section 4.2 above, provided, however, that (i) an Ipsen Sublicense Share shall be creditable against future Milestone Payments only once; (ii) if an Ipsen Sublicense Share is credited only partially against a Milestone Payment, the remaining non-credited amount of such Ipsen Sublicense Share shall be creditable against future Milestone Payment(s); and

(c) once all Milestone Payments have been triggered and credited against Ipsen Sublicense Share(s), ACADIA shall pay to IPSEN all forthcoming Ipsen Sublicense Share(s) without any deduction.

For the avoidance of doubt, the parties acknowledge that, it is their intention that, under this Section 4.4, ACADIA pays to IPSEN the higher of (i) the total amount of Milestone Payments triggered as provided for in Section 4.2 of this Agreement and (ii) the total amount of the Ipsen Sublicense Shares. An example of the mechanism of credit of Milestone Payments and Ipsen Sublicense Shares is attached as Exhibit D of this Agreement.

4.5 Royalty Payments . ACADIA shall pay to IPSEN on a product-by-product and country-by-country basis a royalty calculated as detailed in Exhibit E (collectively, the “ Royalty Payments ”).

5.1 Reports and Payments . Beginning with the first Commercial Sale in the Territory, ACADIA shall provide to IPSEN a quarterly payment report as follows: Within sixty (60) days after the end of each calendar quarter, ACADIA shall deliver to IPSEN a true and accurate report, giving such particulars of the business conducted by ACADIA, its Affiliates and Sublicensees, if any, during such calendar quarter as are pertinent to account for Royalty Payments due under Section 4.5 of this Agreement. Such report shall include at least (i) the total of Net Sales during such quarter on a country-by-country basis; (ii) the calculation of Royalty Payments under this Agreement; and (iii) the total Royalty Payments so calculated and due to IPSEN. Simultaneously with the delivery of each such report, ACADIA shall pay to IPSEN the total Royalty Payments, if any, due to IPSEN for the period of such report. If no Royalty Payments are due, ACADIA shall so report.

5.2 Calculation of Net Sales . All Royalty Payments to IPSEN under this Agreement shall be made in U.S. dollars. When calculating Net Sales, ACADIA shall convert the amount of invoiced sales in currencies other than U.S. dollars into U.S. dollars using an exchange rate equal to the weighted average of the rates of exchange for the currency of the country from which the Royalty Payments are payable as published by The Wall Street Journal, New York edition, (or by the Financial Times, should such currency not be published in The Wall Street Journal) during the calendar quarter for which a payment is due.

5.3 Method of Payments . All payments hereunder shall be made by electronic transfer in immediately available funds via either bank wire transfer, an ACH (automated clearing house) mechanism, or any other means of electronic funds transfer, at ACADIA’s election, to such bank accounts as IPSEN shall designate. All payments under this Agreement which are not paid when due shall bear interest from the date due until paid at a rate equal to the one-month European Interbank Offered Rate (EURIBOR) as reported by the European Banking Federation (or a successor or similar organization) plus four percent (4%) effective from the date that payment was due.

5.4 Inspection of Records . ACADIA shall keep, and shall cause its Affiliates and Sublicensees to keep, full and accurate books and records setting forth gross sales of each Licensed Product, Net Sales of each Licensed Product, itemized deductions from gross sales taken to calculate Net Sales and Royalty Payments payable hereunder to IPSEN for each such Licensed Product.

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ACADIA shall permit IPSEN, by independent qualified public accountants (the “ Auditors ”) selected by IPSEN and accepted by ACADIA, to examine such books and records at any reasonable time. Such audit shall be binding upon the Parties should ACADIA have accepted the Auditors selected by IPSEN within thirty (30) days as from notification by IPSEN of its intent to conduct an inspection and of the identity of the Auditors selected by IPSEN for this purpose (absence of answer from ACADIA within this thirty-day period being deemed to be an approval of the Auditors by ACADIA). In the event ACADIA notifies its refusal to approve the appointment of the Auditors, the parties shall use reasonable commercial efforts to agree upon other Auditors within sixty (60) days as from the date of ACADIA’s notification. Should the parties fail to agree upon such Auditors, IPSEN shall have the right to appoint any Auditors for the purpose of conducting the inspection of ACADIA’s records. The Auditors may be required by ACADIA to enter into a reasonably acceptable confidentiality agreement, and in no event shall the Auditors disclose to IPSEN any information other than such as relates to the accuracy of reports and payments made or due hereunder. IPSEN shall bear the cost of any such examination and review; provided that if the inspection and audit shows an underpayment of Royalty Payments of more than five percent (5%) of the amount due for the applicable period, then ACADIA shall promptly reimburse IPSEN for all external costs incurred in connection with such examination and review. ACADIA shall promptly pay to IPSEN the amount of any such underpayment revealed by an examination and review together with late payment interest pursuant to Section 5.3 of this Agreement. Any overpayment of Royalty Payments by ACADIA revealed by an examination and review shall be fully-creditable against future Royalty Payments, as applicable, under Section 4.5 of this Agreement. Absent manifest error, the Auditors’ report shall be binding upon the parties in the case these Auditors have been accepted by ACADIA or chosen by mutual agreement of the parties.

5.5 Withholding Taxes . If provision is made in law or regulation of any country in the Territory for withholding of taxes of any type, levies or other charges with respect to any amounts payable by ACADIA to IPSEN pursuant to this Agreement, ACADIA shall deduct the amount of such taxes from the payment to IPSEN and shall promptly pay such tax, levy or charge for and on behalf of IPSEN to the proper governmental authority and ACADIA shall promptly furnish IPSEN with certificate of taxes deducted under such withholding tax laws. IPSEN and ACADIA shall cooperate with each other in obtaining any exemption from or reduced rate of tax available under any applicable law or tax treaty.

Except as set forth above, ACADIA and IPSEN shall pay for their own account all sales, turnover, income, revenue, value added and other taxes levied on account of payments accruing or made under this Agreement. All amounts expressed in this Agreement exclude such taxes which where required by law shall be charged at the applicable rate.

6.1 Prosecution and Maintenance . IPSEN shall be solely responsible, at its own expense, for the prosecution and maintenance of the Ipsen Patent Rights. IPSEN agrees to keep ACADIA reasonably informed regarding such prosecution and maintenance and to solicit and reasonably consider ACADIA’s suggestions and comments regarding all material aspects of such patent prosecutions. If IPSEN decides to abandon any patents or patent applications within the Ipsen

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Patent Rights, ACADIA shall have the option to con