WYETH EXECUTIVE RETIREMENT PLAN (amended and restated effective as of January 1, 2005)

Exhibit 10.56

WYETH

EXECUTIVE RETIREMENT PLAN

(amended and restated effective as of January 1, 2005)

PURPOSE

The purpose of the Plan is to provide competitive executive retirement benefits for key executives and to enhance the ability of the Company to attract and retain key senior executives. The Plan is intended to constitute an unfunded deferred compensation plan for a select group of management or highly compensated employees within the meaning of ERISA, and shall be construed and administered accordingly.

The Plan is an amendment and restatement of the Prior Plan, effective as of the Restatement Date.

Capitalized terms not otherwise defined in the text hereof shall have the meanings set forth in Section 1.

SECTION 1 DEFINITIONS

1.1 Rules of Construction . Except where the context indicates otherwise, any masculine terminology used herein shall also include the feminine gender, and the definition of any term herein in the singular shall also include the plural. All references to sections and appendices are, unless otherwise indicated, to sections or appendices of the Plan.

1.2 Terms Defined in the Plan . Whenever used herein, the following terms shall have the meanings set forth below:

(a) “ 25, 50, 75 or 100% Joint and Survivor Annuity ” has the meaning set forth in Section 5.6(a)(2).

(b) “ 409A Benefit ” has the meaning set forth in Section 4.5(b).

(c) “ Administrative Record Keeper ” means the person or persons designated by the Committee in accordance with Section 2.

(d) “ Affiliate ” means any corporation which is included in a controlled group of corporations (within the meaning of Section 414(b) of the Code) which includes Wyeth and any trade or business (whether or not incorporated) which is under common control with Wyeth (within the meaning of Section 414(c) of the Code); provided , however , that in applying Section 1563(a)(1), (2), and (3) of the Code for purposes of determining a controlled group of corporations under Section 414(b) of the Code the language “at least 50 percent” shall be used instead of “at least 80 percent” in each place it appears in Section 1563(a)(1), (2) and (3) of the Code, and in applying Section 1.414(c)-2 of the Treasury Regulations, for purposes of determining trades or businesses (whether or not incorporated) that are under common control for purposes of Section 414(c) of the Code, “at least 50 percent” shall be used instead of “at least 80 percent” in each place it appears in Section 1.414(c)-2 of the Treasury Regulations.

(e) “ Annual Pension Earnings ” means the sum of a Participant’s (i) base salary rate (without regard to salary deferral contributions subject to Section 401(k) of the Code and elective contributions to a plan subject to Sections 125 and 132(f) of the Code) as of January 1 ^st of each calendar year and (ii) any cash bonuses paid by the Company in such calendar year in each case calculated as if (A) the Participant’s compensation for each calendar year included the Participant’s Deferrals for each such year and (B) the Code Limits did not apply.

(f) “ Beneficiary ” means, with respect to death benefits payable under Sections 5.2(c), 5.3(e), 5.6(a)(3), 5.6(a)(4) and 5.7, as applicable, a Participant’s Surviving Spouse or, if there is no Surviving Spouse, the Participant’s estate. Participants shall not be permitted or required to make Beneficiary designations under the Plan. If the Surviving Spouse of a Participant is legally impaired or prohibited from receiving any amounts under the Plan otherwise payable to a Beneficiary, the Participant’s Beneficiary shall be the Participant’s estate. The term Beneficiary shall not refer to any “contingent annuitant” applicable to a Participant in connection with a Payment Form.

(g) “ Board of Directors ” means the Board of Directors of Wyeth (or any committee of the Board of Directors to whom the Board of Directors delegates, from time to time, its authority hereunder).

(h) “ Business Day ” means each day on which the New York Stock Exchange is open for business.

(i) “ Claimant ” has the meaning set forth in Section 8.1.

(j) “ Code ” means the Internal Revenue Code of 1986, as amended, and any applicable rulings and regulations promulgated thereunder.

(k) “ Code Limits ” means Sections 401(a)(17) and 415 of the Code and any other provisions of the Code which limit the amount of benefits that a Participant may accrue or receive under or from the Retirement Plan.

(l) “ Committee ” means the Compensation and Benefits Committee of the Board of Directors and any successor thereto.

(m) “ Company ” means Wyeth and its Affiliates.

(n) “ Company Non-Account Plan ” means any arrangement sponsored by the Company, other than the Plan, that is a “non-account balance plan,” as such term is defined under Section 409A and that is required to be aggregated with the Plan under Treasury Regulation 1.409A-1(c)(2)(C).

(o) “ Credited Service ” has the meaning ascribed to it in the Retirement Plan as of January 1, 2006, and, prior to such date, has the meaning ascribed to “Wyeth Service”, as such term was defined in the Retirement Plan prior to January 1, 2006. Under the terms of the Prior Plan and continuing under the Plan, effective June 16, 2004, Credited Service also includes all service with any Affiliate (including any non-U.S. Affiliate).

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(p) “ DCP ” means the Prior DCP and the New DCP.

(q) “ DCP Option ” has the meaning set forth in Section 5.6(a)(6).

(r) “ Default Payment Form ” means (i) with respect to a Participant’s Grandfathered Benefit, the form of payment elected by such Participant under the Retirement Plan in connection with the Participant’s Separation from Service; and (ii) with respect to a Participant’s 409A Benefit, the Lump-Sum Option; provided , however , that if the Participant participates in the SERP prior to becoming eligible to participate in the Plan, his Default Payment Form under the Plan shall be his “Payment Form” under the SERP.

(s) “ Deferral Plan ” means each of the DCP, the Wyeth Supplemental Employee Savings Plan, as amended from time to time, and/or any other non-qualified plan of the Company designated from time to time by the Committee pursuant to which Participants may elect to defer annual, base compensation or annual, cash bonus compensation, sales bonuses or sales commissions.

(t) “ Deferrals ” means any cash compensation earned by a Participant from the Company that is not taken into account in determining a Participant’s accrued benefit under the Retirement Plan because of the Participant’s election under a Deferral Plan to defer the receipt of such compensation.

(u) “ Deferred Compensation Tax Compliance Committee ” means a committee of such officers and/or employees of the Company as shall be designated from time to time by the Board.

(v) “ Delayed Payment Amount ” has the meaning set forth in Section 5.7.

(w) “ Early Commencement Factors ” means the factors set forth in Appendix A .

(x) “ Elected Payment Date ” means (i) with respect to the Grandfathered Benefit, the first day of any month after a Participant’s Separation from Service elected by the Participant in accordance with Section 5.2 and/or (ii) with respect to the 409A Benefit, the Normal Payment Date, unless the Participant elects the DCP Option in accordance with Section 5.3, or elects to redefer his 409A Benefit into the DCP in accordance with Section 7, in which case the Elected Payment Dates shall be determined in accordance with the applicable terms of the DCP.

(y) “ Elected Payment Form ” means the Payment Form elected by a Participant (i) for the payment of his Grandfathered Benefit in accordance with Section 5.2, and/or (ii) for the payment of his 409A Benefit in accordance with Section 5.3 or Section 7.

(z) “ Eligible Employee ” means an employee (i) who is a Participant in the Retirement Plan; and (ii) who has attained age 55; and (iii) who satisfies one of the following conditions: (A) has a Rate of Salary equal to or in excess of the Minimum Eligible Compensation Level in effect at that time; (B) has been elected or appointed by the Board of Directors as a Member of the Wyeth Management Committee; or (C) has been selected by the Chief Executive Officer for participation in the Plan, and such participation has been approved by the Board of

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Directors. Notwithstanding the foregoing, effective December 1, 2008, the individual serving as Chief Financial Officer of Wyeth may participate in the Plan even if he does not satisfy the age requirement in (ii) above.

(aa) “ ERISA ” means the Employee Retirement Income Security Act of 1974, as amended from time to time, including any applicable rulings and regulations promulgated thereunder.

(bb) “ Final Average Annual Pension Earnings ” means the average of a Participant’s highest Annual Pension Earnings for the three calendar years during the ten calendar-years immediately preceding the date of his Separation from Service.

(cc) “ Grandfathered Benefit ” means the portion of a Participant’s Plan Benefit that, for purposes of Section 409A, was both earned and vested as of December 31, 2004.

(dd) “ Guaranteed Death Benefit Option ” has the meaning set forth in Section 5.6(a)(4).

(ee) “ Key Employee ” means (i) each “specified employee,” as defined in Section 409A(a)(2)(B)(i) of the Code, who meets the requirements of Section 416(i)(1)(A)(i), (ii) or (iii) of the Code (applied in accordance with the regulations thereunder and disregarding Section 416(i)(5) of the Code) at any time during the 12-month period ending on December 31 ^st of a calendar year and (ii) to the extent not otherwise included in (i) hereof, each of the top-100 paid individuals (based on taxable wages for purposes of Section 3401(a) of the Code as reported in Box 1 of Form W-2 for the 12-month period ending on December 31 ^st of such calendar year, plus amounts that would be included in wages for such 12-month period but for pre-tax deferrals to a tax-qualified retirement plan or cafeteria plan or for qualified transportation benefits) who performed services for the Company at any time during the 12-month period ending on December 31 ^st of such calendar year. A Participant shall be treated as a Key Employee for the 12-month period beginning on April 1 ^st of the calendar year following the calendar year for which the determination under clause (i) or (ii) of this definition is made.

(ff) “ Lump-Sum Option ” has the meaning set forth in Section 5.6(a)(5).

(gg) “ Minimum Eligible Compensation Level ” means, effective as of January 1, 2008, a Rate of Salary equal to or greater than Four Hundred Thirty Thousand Dollars ($430,000), which amount shall be adjusted annually by the Annual Approved U.S. Merit Guideline, rounded down to the nearest ten thousand dollars ($10,000).

(hh) “ New DCP ” means the Wyeth 2005 (409A) Deferred Compensation Plan, as amended and restated as of the Restatement Date, as subsequently amended from time to time thereafter.

(ii) “ Normal Retirement Date ” means the first day of the first month following a Participant’s 60 ^th birthday, unless such birthday falls on the first of the month, in which case Normal Retirement Date means the Participant’s 60 ^th birthday.

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(jj) “ Normal Payment Date ” means (i) with respect to a Participant’s Grandfathered Benefit, the first day of the month on which benefits commence to be paid to the Participant under the Retirement Plan; and (ii) with respect to a Participant’s 409A Benefit, the following: (A) for a Participant who incurs a Separation from Service with a Vested Plan Benefit prior to attaining age 55, the first day of the month coincident with or next following the month in which he attains age 55; and (B) for a Participant who incurs a Separation from Service with a Vested Plan Benefit on or after attaining age 55, the first day of the month following his Separation from Service.

(kk) “ Participant ” means an Eligible Employee who has met the requirements for participation in the Plan in accordance with Section 3.

(ll) “ Payment Date ” means the Elected Payment Date or, if no such date has been elected or is permitted to be elected by the Participant, the Normal Payment Date, in each case, for the commencement of payment of a Plan Benefit.

(mm) “ Payment Delay Period ” means, solely with respect to a Lump-Sum Option payment of a Participant’s Grandfathered Benefit, the twelve-month period beginning on the first day of the month following the month in which occurs the Participant’s Separation from Service.

(nn) “ Payment Election ” means the elections made by a Participant for his Grandfathered Benefit and/or 409A Benefit, as applicable, under Section 5 or Section 7, as applicable.

(oo) “ Payment Form ” means the Elected Payment Form or, if no such form is elected or is permitted to be elected by a Participant, the Default Payment Form, in each case for the payment of a Plan Benefit.

(pp) “ Plan ” means this Wyeth Executive Retirement Plan, as amended from time to time.

(qq) “ Plan Benefit ” means, as of a given date, the benefit, expressed as a Single Life Annuity commencing at the Participant’s Normal Retirement Date, that a Participant has accrued under the Plan in accordance with Section 4.2.

(rr) “ Prior DCP ” means the terms of the Wyeth Deferred Compensation Plan (as amended and restated as of November 20, 2003), as set forth in the Company’s written documentation, rules, practices and procedures applicable to such plan (but without regard to any amendments thereto after October 3, 2004 that would result in any material modification of such plan, within the meaning of Section 409A).

(ss) “ Prior Plan ” means the terms of the Plan in effect immediately prior to the Restatement Date, as set forth in the Company’s written documentation, rules, practices and procedures applicable to the Plan (but without regard to any amendments thereto after October 3, 2004 that would result in any material modification of the Grandfathered Benefit, within the meaning of Section 409A).

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(tt) “ Puerto Rico Participant ” means a Participant employed by the Company in Puerto Rico and who resides in Puerto Rico.

(uu) “ Rate of Salary ” means the annual rate of an employee’s base salary from the Company, as in effect on the applicable date of determination, and prior to any Deferrals.

(vv) “ Restatement Date ” means January 1, 2005.

(ww) “ Retirement Eligible ” means a Participant who, as of the date of his Separation from Service, is (i) at least age 55 with at least five Years of Vesting Service or (ii) at least age 60.

(xx) “ Retirement Plan ” means the Wyeth Retirement Plan – United States, as amended from time to time.

(yy) “ Section 409A ” means Section 409A of the Code and the applicable notices, rulings and regulations promulgated thereunder.

(zz) “ Section 409A Compliance ” has the meaning set forth in Section 9.1.

(aaa) “ Separation from Service ” means a separation from service with the Company for purposes of Section 409A, determined using the default provisions set forth in Treasury Regulation Section 1.409A-1(h); provided, however, that, for purposes of the Grandfathered Benefit, “Separation from Service” shall be determined in accordance with the terms of the Prior Plan. Notwithstanding the foregoing, if a Participant would otherwise incur a Separation from Service in connection with a sale of assets of the Company, the Company shall retain the discretion to determine whether a Separation from Service has occurred in accordance with Treasury Regulation Section 1.409A-1(h)(4).

(bbb) “ SERP ” means the Wyeth Supplemental Executive Retirement Plan, as amended from time to time.

(ccc) “ SERP 409A Benefit ” means the portion of a Participant’s benefit under the SERP that is subject to Section 409A of the Code.

(ddd) “ Single Life Annuity ” has the meaning set forth in Section 5.6(a)(1).

(eee) “ Social Security Benefit ” means the estimated annual amount of an employee’s old age retirement benefits that a Participant shall receive under the United States Social Security system.

(fff) “ Surviving Spouse ” means the individual to whom a Participant was legally married, for federal law purposes, for a continuous period of at least one year as of the date of the Participant’s death.

(ggg) “ Ten Year Certain and Life Option ” has the meaning set forth in Section 5.6(a)(3).

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(hhh) “ Transition Elections ” means elections made by a Participant prior to January 1, 2009 in accordance with the provisions of Notices 2005-1, 2006-79 and 2007-86, promulgated by the U.S. Treasury Department and the Internal Revenue Service and the Proposed Regulations under Section 409A, 70 Fed. Reg. 191 (Oct 4, 2005).

(iii) “ Treasury Regulations ” means the regulations adopted by the Internal Revenue Service under the Code, as they may be amended from time to time.

(jjj) “ Valid Notional Rollover ” means a notional rollover constituting a full and complete settlement of the Company’s obligations to the Participant under the Plan with respect to the portion of the Grandfathered Benefit credited to the Prior DCP or the portion of the 409A Benefit credited to the New DCP by a Participant who is Retirement Eligible at the time of his Separation from Service.

(kkk) “ Vested Plan Benefit ” means a Plan Benefit that has vested in accordance with Section 4.4.

(lll) “ Wyeth ” means Wyeth, a Delaware corporation, and any successor thereto.

(mmm) “ Wyeth Retirement Plans ” means the Retirement Plan, the SERP, the American Cyanamid and Subsidiaries Supplemental Employees Retirement Plan, the American Cyanamid and Subsidiaries ERISA Excess Plan and/or any other retirement plan or arrangement of the Company to the extent it provides retirement or pension benefits (but only to the extent that service under such plan is counted for purposes of the Retirement Plan), each as amended from time to time.

(nnn) “ Year of Vesting Service ” has the meaning ascribed to it in the Retirement Plan as of January 1, 2006 and, prior to such date, has the meaning ascribed to “Continuous Service”, as such term was defined in the Retirement Plan prior to January 1, 2006.

SECTION 2 ADMINISTRATION

2.1 General Authority . The general supervision of the Plan shall be the responsibility of the Committee, which, in addition to such other powers as it may have as provided herein, shall have the power, subject to the terms of the Plan: (i) to determine eligibility to participate in, and the amount of benefit to be provided to any Participant under, the Plan; (ii) to make and enforce such rules and regulations as it shall deem necessary or proper for the efficient administration of the Plan; (iii) to determine all questions arising in connection with the Plan, to interpret and construe the Plan, to resolve ambiguities, inconsistencies or omissions in the text of the Plan, to correct any defects in the text of the Plan and to take such other action as may be necessary or advisable for the orderly administration of the Plan; (iv) to make any and all legal and factual determinations in connection with the administration and implementation of the Plan; (v) to designate the Administrative Record Keeper and to review actions taken by the Administrative Record Keeper or any other person to whom authority is delegated under the Plan; and (vi) to employ and rely on legal counsel, actuaries, accountants and any other agents as may be deemed to be advisable to assist in the administration of the Plan. All such actions of the Committee shall be

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conclusive and binding upon all persons. The Committee shall be entitled to rely conclusively upon all tables, valuations, certificates, opinions, and reports furnished by any actuary, accountant, controller, counsel, or other person employed or engaged by the Company with respect to the Plan. If any member of the Committee is a Participant, such member shall not resolve, or participate in the resolution of, any matter relating specifically to such Committee member’s eligibility to participate in the Plan or the calculation or determination of such member’s Plan Benefit.

2.2 Delegation . The Committee shall have the power to delegate to any person or persons the authority to carry out such administrative duties, powers and authority relative to the administration of the Plan as the Committee may from time to time determine. Any action taken by any person or persons to whom the Committee makes such a delegation shall, for all purposes of the Plan, have the same force and effect as if undertaken directly by the Committee. If any individual to whom the Committee delegates authority is a Participant, such individual shall not resolve, or participate in the resolution of, any matter specifically relating to such individual’s eligibility to participate in the Plan or the calculation or determination of such individual’s Plan Benefit.

2.3 Administrative Record Keeper . The Administrative Record Keeper shall be responsible for the day-to-day operation of the Plan, having the power (except to the extent such power is reserved to the Committee) to take all action and to make all decisions necessary or proper in order to carry out his duties and responsibilities under the provisions of the Plan. If the Administrative Record Keeper is a Participant, the Administrative Record Keeper shall not resolve, or participate in the resolution of, any question which relates directly or indirectly to him and which, if applied to him, would significantly vary his eligibility for, or the amount of, any benefit to him under the Plan. The Administrative Record Keeper shall report to the Committee at such times and in such manner as the Committee shall request concerning the operation of the Plan.

2.4 Actions; Indemnification . The members of the Board of Directors, the Committee, the Administrative Record Keeper, the members of the Deferred Compensation Tax Compliance Committee, the members of any other committee and any director, officer or employee of the Company to whom responsibilities are delegated by the Board of Directors shall not be liable for any actions or failure to act with respect to the administration or interpretation of the Plan, unless such person acted in bad faith or engaged in fraud or willful misconduct. The Company shall indemnify and hold harmless, to the fullest extent permitted by law, the Board of Directors (and each member thereof), the Committee (and each member thereof), the Deferred Compensation Tax Compliance Committee (and each member thereof), the Administrative Record Keeper, the members of any other committee and any director, officer or employee of the Company to whom responsibilities are delegated by the Committee from and against any liabilities, damages, costs and expenses (including attorneys’ fees and amounts paid in settlement of any claims approved by the Company) incurred by or asserted against it or him by reason of its or his duties performed in connection with the administration or interpretation of the Plan, unless such person acted in bad faith or engaged in fraud or willful misconduct. The indemnification, exculpation and liability limitations of this Section 2.4 shall apply to the Administrative Record Keeper only to the extent that the Administrative Record Keeper is or was a director, officer or employee of the Company.

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SECTION 3 PARTICIPATION

3.1 Continuing Participants . Any individual who participated in the Prior Plan immediately prior to the Restatement Date shall continue to be a Participant in the Plan on the Restatement Date, including, without limitation, individuals who became Participants in the Prior Plan prior to age 55 under the eligibility rules of the Prior Plan.

3.2 New Participants . An employee of the Company who does not become a Participant in the Plan in accordance with Section 3.1 shall commence participation in the Plan as of the date on which such employee first becomes an Eligible Employee. Eligible Employees shall not accrue any Plan Benefit prior to their commencement of participation in the Plan; provided that when participation commences a Participant’s accrued Plan Benefit shall be calculated as of the later of the date the Participant was first employed by the Company and the date the Participant reached age 21.

3.3 Enrollment . Each Participant shall complete, execute and return to the Administrative Record Keeper such forms as are required from time to time by the Administrative Record Keeper, and such forms shall be submitted to the Administrative Record Keeper within such time periods specified by the Administrative Record Keeper. A Participant’s failure to submit in a complete and timely manner any such forms to the Administrative Record Keeper shall subject the Participant to the default rules specified in the Plan. For purposes of the Plan, “forms” prescribed by the Administrative Record Keeper can be in paper, electronic or such other media (or combination thereof) as the Administrative Record Keeper shall specify from time to time.

3.4 Exclusions . No employee of the Company who is not an Eligible Employee shall be eligible to participate in the Plan.

SECTION 4 PLAN FORMULA AND VESTING

4.1 Applicability of Prior Plan . The benefit payable to a Participant who had a Separation from Service prior to the Restatement Date shall be governed by the terms of the Prior Plan as in effect on the date of his Separation from Service.

4.2 Plan Benefit Formula . The Plan Benefit of a Participant who has a Separation from Service on or after the Restatement Date shall equal the positive difference , if any, that results from subtracting the amount determined under Section 4.2(b) from the amount determined under Section 4.2(a):

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Less     

4.3 Additional Credited Years of Bridge Service . The three (3) additional years of Credited Service described in Section 4.2(a) shall be reduced by one (1) year for each year of service (or part thereof) that the Participant’s age as of the date of the Participant’s Separation from Service exceeds 62; provided, however, that a Participant who commences participation in the Plan at age 61 or later shall accrue a Plan Benefit in the amount provided in Section 4.2(a) for two (2) years before such reductions take effect.

4.4 Vesting . Anything in the Plan to the contrary notwithstanding, no Plan Benefit or other amount shall be payable to a Participant under the Plan unless the Participant has either (i) completed five Years of Vesting Service or (ii) is at least age 60, in each case as of the date of the Participant’s Separation from Service.

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4.5 Plan Benefit Components .

(a) Grandfathered Benefit .

(b) 409A Benefit . A Participant’s 409A Benefit shall mean any portion of the Participant’s Plan Benefit which is not a Grandfathered Benefit.

(c) Special Adjustment at Separation from Service to the 409A Benefit . Solely to the extent necessary to comply with Section 409A, a special allocation shall be made to the Plan Benefit of a Participant who was not eligible to retire under the Plan as of December 31, 2004 with a subsidized early retirement benefit (solely by reason of the Participant as of December 31, 2004, not having ten or m