**Exhibit 10.13(c)**

**AMENDMENT**

**TO THE**

**SUPPLY AGREEMENT**

This Amendment(the “Amendment”) entered into effective as of December 21, 2006 (the “AmendmentEffective Date”) to the Supply Agreement, effective as of June 23, 2005(the “Supply Agreement”), by and between Alkermes, Inc. (“Alkermes”)and Cephalon, Inc. (“Cephalon”), witnesseth that (capitalized terms usedbut not defined herein shall have the meaning set forth in the SupplyAgreement):

**RECITALS:**

WHEREAS, pursuantto the Supply Agreement, the Parties agreed, among other things, that Alkermeswas responsible for providing the capital necessary to permit the Manufactureof the Product Requirements pursuant to such Supply Agreement; and

WHEREAS, Alkermesand Cephalon have now agreed to amend the terms and conditions governingresponsibilities for providing the capital necessary to meet the ProductRequirements for the Product.

NOW, THEREFORE, inconsideration of the premises and the mutual covenants and agreements set forthherein, and other good and valuable consideration, the receipt and sufficiencyof which are hereby acknowledged, the Parties agree as follows:

**1.****                                     **Anew Section 5.5 shall be added to the Supply Agreement and shall read asfollows:

**“5.5****                        Line 5 andLine 6.**

**(a)           Product Manufacturing Equipment Purchase**.  Notwithstanding anything to the contraryherein, effective the Amendment Effective Date, Alkermes will sell and Cephalonwill purchase for the Purchase Price described below all equipment that onSeptember 30, 2006 (the “Agreement Date”) constituted the second wetprocess line for the Manufacture of the Product at the Alkermes ManufacturingFacility in Wilmington, Ohio (“Line 5”) and the third wet process linefor the Manufacture of the Product at the Alkermes Manufacturing Facility inWilmington, Ohio (“Line 6”) (such equipment along with all otherequipment thereafter added to Line 5 and Line 6, the “Product ManufacturingEquipment”) as well as reimburse Alkermes for all related CapitalImprovements (as defined below) made prior to the Agreement Date.  Within ten (10) days of the AmendmentEffective Date, Cephalon will pay Alkermes the purchase price of NineteenMillion Three Hundred Fifty-Six Thousand Seven Hundred Fifty-Six Dollars($19,356,756) (the “Purchase Price”). Upon receipt of the Purchase Price Alkermes will transfer to Cephalonthe title to and risk of loss of all Product Manufacturing Equipment inexistence on the Agreement Date and all Capital Improvements made prior to theAgreement Date.  Thereafter, Alkermeswill supply to Cephalon at the end of each 

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calendar quarter a detailed listing of all CapitalImprovements made to Line 5 and Line 6 during such calendar quarter and willsupply supporting documentation for all Fully Capitalized Costs (as definedbelow) incurred by Alkermes as requested by Cephalon from time to time.

Notwithstanding anything to the contrary herein, whether or notAlkermes has supplied to Cephalon any listing thereof in accordance with thepreceding paragraph, Cephalon will own any Product Manufacturing Equipment andother Capital Improvements made to Line 5 or Line 6 for which Cephalon has madethe related payment to Alkermes of Fully Capitalized Costs pursuant to Section5.5(b).  To evidence and perfect Cephalon’sownership interest in the Product Manufacturing Equipment and other CapitalImprovements, Alkermes agrees to execute and deliver all deeds, assignments,bills of sale and other documents reasonably requested by Cephalon, includingappropriate Uniform Commercial Code financing statements with respect to theProduct Manufacturing Equipment and other Capital Improvements.  Alkermes will keep the Product ManufacturingEquipment and other Capital Improvements free and clear of all liens andencumbrances, other than those which may result from any act of Cephalon.  All costs incurred by Cephalon for insuringthe Product Manufacturing Equipment and other Capital Improvements, and forpaying any taxes, including personal property and sales taxes that may accruewith respect to the Product Manufacturing Equipment and other CapitalImprovements, shall be deemed to be Cephalon Incurred Shared Expenses.

**(b)           CapitalImprovements**.  Following the Agreement Date, Alkermes hascontinued and will continue to design, engineer, procure additional equipmentfor, develop, construct and validate Line 5 and Line 6 (all such activities the“Capital Improvements”).  Within ten (10) days of the AmendmentEffective Date, Cephalon will reimburse Alkermes for the Fully CapitalizedCosts of Capital Improvements incurred by Alkermes during October 2006 andany other Fully Capitalized Costs associated with Line 5 and Line 6 incurred byAlkermes during this period.  Within the period ending thirty (30) daysafter the later of (i) the Amendment Effective Date or (ii) Cephalon’s receiptof Alkermes’ invoice therefor, Cephalon will reimburse Alkermes for the FullyCapitalized Costs of Capital Improvements incurred by Alkermes during November2006 and any other Fully Capitalized Costs associated with Line 5 andLine 6 incurred by Alkermes during this period. Within fifteen (15) days of theend of each month after the Amendment Effective Date, Alkermes will invoiceCephalon for the Fully Capitalized Costs of Capital Improvements incurred byAlkermes during the prior month and any other Fully Capitalized Costsassociated with Line 5 and Line 6 incurred by Alkermes during such period.  Cephalon will pay each such invoice withinthirty (30) days of receipt; provided, however, that Cephalonshall not be obligated to pay pursuant to this Section 5.5(b) for any FullyCapitalized Costs exceeding in the aggregate Fifty-One Million Six HundredForty-Three Thousand Two Hundred Forty-Four Dollars ($51,643,244).  All costs incurred by Alkermes with respectto Line 5 and Line 6 that are not 

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reimbursed by Cephalonpursuant to this Section 5.5(b) or included in the Purchase Price will, to theextent covered by Development Plan budgets approved by the JSC, be deemed to beAlkermes Incurred Shared Expenses or, to the extent appropriate, be included inFully Burdened Manufacturing Costs.  “FullyCapitalized Costs” shall mean costs that normally would becapitalized in accordance with Cephalon’s accounting policies (whether incurredby Cephalon or Alkermes), including direct labor costs of both Cephalon and Alkermes as well as out-of-pocket costs, includingout-of-pocket costs incurred for equipment and third-party design, engineering,development, construction and validation services.  Alkermes’ labor costs will be calculated atthe Development FTE Rate.

**(c)           Accounting for Line 5 and Line 6**.  The Purchase Price, the Fully CapitalizedCosts of Capital Improvements and any other Fully Capitalized Costs associatedwith Line 5 and Line 6 reimbursed by Cephalon to Alkermes will be capitalizedby Cephalon in accordance with its accounting policies.  All such amounts will be depreciated byCephalon on a straight line basis over the life of the Product ManufacturingEquipment in accordance with Cephalon’s accounting policies and GAAP and thedepreciation charge each month will be deemed to be Cephalon Incurred SharedExpenses.

**(d)           [**]**, effective the last Business Day ofeach calendar quarter during the life of the Product Manufacturing Equipment,Cephalon will calculate [**] on the total of [**].  The rate used to calculate [**] will be fixedat [**] per annum.  At the end of eachcalendar quarter Cephalon will invoice Alkermes for [**] for that calendarquarter, and Alkermes will pay this invoice within [**] days of receipt.

**(e)**           **Use of ProductManufacturing Equipment**. Alkermes will have the right to use the Product Manufacturing Equipmentin accordance with the provisions of this Agreement and the Amendment withoutany obligation to make any payments to Cephalon with respect to such use.  Subject to its obligations under thisAgreement and the Amendment, Alkermes will have the right at any time tomanufacture products other than the Product using Line 5 and Line 6; provided,however, that in the event Alkermes uses Line 5 or Line 6 to manufactureproducts other than the Product, Alkermes’ costs associated with such use,including maintenance costs, shall not be considered Alkermes Incurred SharedExpenses and Alkermes will reimburse Cephalon for one hundred percent (100%) ofthe depreciation charge for the Fully Capitalized Costs for Line 5 or Line 6for the period and to the extent Line 5 or Line 6 is used by Alkermes tomanufacture products other than the Product, which fully reimburseddepreciation charge for such period shall not be considered Alkermes IncurredShared Expenses or Cephalon Incurred Shared Expenses.  Alkermes will maintain each piece of ProductManufacturing Equipment in good operating order and repair, normal wear andtear excepted, and, subject to the preceding sentence, the expense of suchmaintenance will be deemed to be an Alkermes Incurred Shared Expense.

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**Portions of thisexhibit have been omitted and have been filed separately pursuant to anapplication for confidential treatment filed with the Securities and ExchangeCommission pursuant to Rule 24b-2 under the Securities Exchange Act of 1934, asamended.

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**(f)**            **Abandonment of ProductManufacturing Equipment**.  Ifat any time prior to termination of this Agreement the Product ManufacturingEquipment is deemed to be impaired, abandoned or obsolete in accordance withCephalon’s accounting policies, then any impairment charge will be deemed to bea Cephalon Incurred Shared Expense.

**(g)           Repurchase of Product Manufacturing Equipment.**  At any time after December 21, 2008 or in theevent the Parties enter into a Technology Transfer Agreement, Alkermes willhave an option to purchase all Product Manufacturing Equipment as installed(including any development and/or validation data or information) and otherCapital Improvements at their net book value in Cephalon’s financial statementsat the time of option exercise.  Inaddition, in the event of expiration or termination of this Agreement (a “TerminationEvent”), Alkermes will have an option to purchase all Product ManufacturingEquipment as installed (including any development and/or validation data orinformation) and other Capital Improvements at their net book value in Cephalon’sfinancial statements on the date of such Termination Event, [**], as set forthin Cephalon’s financial statements on the date of such Termination Event.  Within thirty (30) days of a notice from Alkermesof its interest in exercising any such repurchase option, Cephalon will provideAlkermes with notice of the Product Manufacturing Equipment’s and the relevantFully Capitalized Costs’ then current net book value.  Alkermes will have the right to request anaudit of Cephalon’s determination of net book value of the ProductManufacturing Equipment and such Fully Capitalized Costs, which shall beconducted by an independent public accountant of national prominence atAlkermes’ expense.  Such accountant willtreat all information subject to audit under this Section 5.5(g) asconfidential and will provide a report to Alkermes and Cephalon regarding onlythe accuracy or inaccuracy of the net book value determination.  Following receipt of Cephalon’s notice regardingthe net book value of the Product Manufacturing Equipment and the FullyCapitalized Costs (and any audit conducted by Alkermes), Alkermes will provideCephalon notice of whether it intends to purchase the Product ManufacturingEquipment and other Capital Improvements. If Alkermes provides notice of its intended purchase, Alkermes will payCephalon the purchase price described above, and Cephalon will transfer toAlkermes the title to and risk of loss of all Product Manufacturing Equipmentand other Capital Improvements.  Cephalonand Alkermes will promptly execute and deliver all deeds, assignments, bills ofsale and other documents for the purchase of the Product ManufacturingEquipment and other Capital Improvements reasonably requested by Alkermes toevidence and perfect Alkermes’ ownership of the Product Manufacturing Equipmentand other Capital Improvements.  Upon theexecution and delivery of such documents, Cephalon will promptly fileamendments terminating any Uniform Commercial Code financing statements thathave been filed with respect to the Product Manufacturing Equipment and otherCapital Improvements.

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**Portions of thisexhibit have been omitted and have been filed separately pursuant to anapplication for confidential treatment filed with the Securities and ExchangeCommission pursuant to Rule 24b-2 under the Securities Exchange Act of 1934, asamended.

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In the event that following a Termination Event or thesignature of a Technology Transfer Agreement, (i) Alkermes provides notice toCephalon that it does not intend to purchase the Product ManufacturingEquipment and other Capital Improvements or (ii) in response to an inquiry fromCephalon, Alkermes indicates that it does not intend to purchase the ProductManufacturing Equipment and other Capital Improvements, then Cephalon mayrequest that Alkermes arrange for the removal from the Alkermes ManufacturingFacility in Wilmington, Ohio of the Product Manufacturing Equipment.  TheParties will work together in good faith to determine a mutually agreeable timeand method for the removal of the Product Manufacturing Equipment from theAlkermes Manufacturing Facility.  Alkermes will then remove, crate and ship suchProduct Manufacturing Equipment in accordance with such plan, at Cephalon’s costand expense, to any destination in the United States that Cephalon maydesignate.  In the event that following aTermination Event or the signature of a Technology Transfer Agreement, Alkermesdetermines that any Product Manufacturing Equipment cannot be so removed fromthe Alkermes Manufacturing Facility without destroying any portion thereof orsignificantly disrupting the operation thereof, Alkermes shall purchase suchProduct Manufacturing Equipment for the purchase price described above.”

**2.****                                     **Exceptas specifically amended herein, all provisions of the Supply Agreement shallremain in full force and effect in accordance with their terms.  In the event of a conflict between theprovisions of the Supply Agreement and those of this Amendment, this Amendmentshall control.  This Amendment, togetherwith the Supply Agreement, represents the entire agreement between the Partiesregarding the subject matter hereof, and there are no prior or contemporaneouswritten or oral promises or representation relating to this subject notincorporated herein, including the Binding Term Sheet between the Parties datedOctober 17, 2006.  No amendment ormodification of the terms and conditions of this Amendment shall be binding on eitherParty unless reduced to a writing referencing this Amendment and signed by anauthorized officer of the Party to be bound.

**3.****                                     **ThisAmendment may be executed in two or more counterparts, each of which shall bedeemed an original for all purposes, but all of which together shall constituteone and the same instrument.  ThisAmendment may be executed and delivered by facsimile and upon such delivery thefacsimile signature will be deemed to have the same effect as if the originalsignature had been delivered to the other Party.

**4.****                                     **ThisAmendment shall be governed by and construed in accordance with the Laws of theState of Delaware (other than its choice of law principles).

***[Signature page follows]***

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IN WITNESSWHEREOF, each of the Parties has caused this Amendment to be executed anddelivered by its duly authorized representatives to be effective as of the dateset forth above.
| **ALKERMES, INC.**    | **CEPHALON,  INC.**                       |
|-----------------------|-------------------------------------------|
|                  |                                      |
|                  |                                      |
| By:                   | /s/ Michael Landine                       |   | By: | /s/ J. Kevin Buchi |   |
| Name: Michael Landine | Name: J. Kevin Buchi                      |
| Title:Vice President  | Title: Executive Vice President & CFO |
|                       |                                           |  |  |  |  |

 

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