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                                                                   Exhibit 10.11
                                                                   -------------




Bausch & Lomb Incorporated
One Bausch & Lomb Place
Rochester, NY 14604

Attn: Gary Aron

Re:   License Agreement

Dear Gary:

     This letter amends, effective as of January 1, 2001, the License Agreement
(the "License Agreement") between us dated as of June 9, 1999.  The parties
shall have no obligations hereunder before the effective date.

     Terms used in this letter that are not otherwise defined in this letter
have the meaning given to them in the License Agreement.

     1.  Notwithstanding any provisions in the License Agreement to the
contrary:

          1.1  Licensor shall assume the responsibility of Licensee set forth in
               Section 17.1 of the License Agreement to manufacture and supply
               to Licensee at no additional cost to Licensee other than as
               stated herein and in the License Agreement, all Licensed Products
               required for Phase III clinical trials. and shall assume primary
               responsibility for all product development, provided, that such
               responsibility for product development shall be subject to the
               direction of the Steering Committee, and shall not affect the
               rights of the parties in and to technology and intellectual
               property as is set forth in the License Agreement.  As a further
               condition precedent to the agreements of Licensee hereunder,
               Licensor repeats and reaffirms as of the date hereof the
               representation and warranty of Licensor set forth in Section 21.2
               of the License Agreement.

          1.2. The funds paid by Licensee to Licensor under this Letter
               Agreement, together with additional funds supplied by Licensor,
               shall cover all necessary capital expenditures, as well as
               material, labor, overhead and all other costs necessary for
               Licensor to perform its obligations hereunder, including, without
               limitation, the cost of Licensor upgrading its manufacturing
               facilities to meet applicable current good manufacturing
<PAGE>

[*]=CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY
BRACKETED ASTERISKS HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES
AND EXCHANGE COMMISSION PURSUANT TO RULE 406 OF THE SECURITIES ACT OF 1933, AS
AMENDED.

               practices standards of the FDA ("GMP"), as well as applicable
               standards of the of the appropriate authorities of the United
               Kingdom (Medicine Control Agency) for the purpose of
               manufacturing Licensed Products.

          1.3. In furtherance of the foregoing, Licensor shall install on its
               premises certain capital equipment which is either newly
               purchased using funds provided by Licensee (the "New Equipment")
               or which is transferred to Licensor's facility from Licensee's
               Tampa, Florida facility (the "Used Equipment") (collectively, the
               New Equipment and the Used Equipment are referred to as the
               "Equipment"). The New Equipment to be purchased and the Used
               Equipment to be transferred are each identified on Schedule 1.3
               to this Amendment.

               Title to the Equipment shall at all times remain with Licensee,
               and the Equipment shall not be transferred or delivered to any
               person, nor shall any lien or encumbrance be placed or permitted
               to be placed on the Equipment.  Licensor shall at all times that
               the Equipment is in its possession keep the Equipment insured
               against loss or damage.  In addition, Licensor shall, while the
               Equipment is in its possession, keep the Equipment maintained and
               in operating order and condition.

               The possession of the Equipment shall be transferred from
               Licensor to Licensee at the direction of the Steering Committee,
               as production is transferred from Licensor to Licensee at
               completion of Phase III clinical trials.  At any time after
               January 1, 2003, Licensee shall be entitled to give Licensor
               notice of Licensee's intent to take possession of all or any
               portion of the Equipment, effective no sooner than six months
               after such notice.  Licensor shall then have the option,
               exercisable at any time within 60 days after receiving the notice
               of Licensee referenced in the foregoing sentence, to purchase all
               or any portion of the Equipment from Licensee at Licensee's then-
               current book value of the Equipment purchased.  Unless otherwise
               agreed by the parties, the purchase price for the Equipment shall
               be paid in cash at the time of transfer, which shall be within
               ten days of Licensor's notice exercising its option.  The
               Equipment shall be transferred pursuant to this option, free and
               clear of liens created by Licensee, and in its then-current "as
               is" condition.

               Each party shall bear out-of-pocket costs associated with the
               transfer of any Equipment to such party's facility, or as
               otherwise directed by such party.

          1.4  As payment for its activities under this Letter Agreement, and
               for the purchase by Licensor on Licensee's behalf of the New
               Equipment, Licensor shall be paid by Licensee the "Year1 and
               Year2 Milestone Payments" set forth below:

               Year1 Milestone Payments totaling $[*] shall be paid in
               four equal installments commencing in the fiscal quarter of
               Licensee immediately following the commencement by Licensor of
               the supply of Licensed Products (as evidenced by manufacture and
               delivery of at least [*] units of acceptable Licensed Products
               for Phase III clinical trials.  The Year1 Milestone Payments
               shall be reduced by the value of additional Used Equipment
               provided by Bausch & Lomb in addition to the Used Equipment. The
               value of the reduction shall equal the value of New Equipment,
               which need not be purchased due to the supply of such added
               equipment by Bausch & Lomb.


<PAGE>

[*]=CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY
BRACKETED ASTERISKS HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES
AND EXCHANGE COMMISSION PURSUANT TO RULE 406 OF THE SECURITIES ACT OF 1933, AS
AMENDED.

               Year2 Milestone Payments totaling $[*] shall be paid in
               four equal installments commencing in the fiscal quarter of
               Licensee immediately following the last to occur of (a) Licensor
               completing the upgrading of its manufacturing facilities to meet
               applicable good manufacturing practices standards of the FDA
               ("GMP"), as well as applicable standards of the of the
               appropriate authorities of the United Kingdom (Medicine Control
               Agency), as certified by a recognized third party auditing firm
               mutually acceptable to Licensee and Licensor, and (b) production
               by Licensor of NDA stability batches in compliance with GMP and
               suitable for submission to applicable regulatory authorities,
               including FDA, as reasonably determined by Licensee.  No Year2
               Milestone payment shall be due before January 1, 2002.

               All such Milestone Payments shall be paid on or before the 10th
               calendar day of the applicable fiscal quarter of Licensee during
               which such amounts become due as set forth above, assuming
               continued performance by Licensor hereunder at the time such
               payment is due.

               To the extent that Licensee manufactures Licensed Products for
               Phase III clinical trials or performs product development work as
               provided in Paragraph 1.1 after 2002 (other than as a result of
               Licensor's failure or delay in meeting the obligations set forth
               above, which are expected to be performed in their entirety
               before 2003), appropriate arrangements will be made by the
               Steering Committee for Licensee to fund the cost of Licensor
               performing such work, provided that if Licensee does not wish to
               provide such funding, Licensee may decline to do so, in which
               event, Licensor shall not be obligated to perform such work.  The
               foregoing proviso shall not, however, limit in any way the
               obligations of Licensor as are set forth in the License Agreement
               (including, without limitation, obligations relating to
               Development of Licensed Products).


          1.5. The amounts payable under Paragraph 1.4 shall be in addition to
               any other amounts payable by Licensee to Licensor under the
               License Agreement.  This is based upon the representation and
               warranty by Licensor that such amounts are in consideration of
               actions not otherwise required under, and in compensation for
               costs and expenditures not otherwise reasonably anticipated or
               budgeted for in connection with, performance by Licensor of its
               obligations under the License Agreement without giving regard to
               this Letter Agreement, as is detailed in the Operations Plan
               Revision 2, dated October 2000, comprising four pages provided by
               Licensor to representatives of Licensee in connection with
               discussions relating to this Letter Agreement, a copy of which is
               attached as schedule 1.5 hereto.  The foregoing representation
               shall be subject to the recordkeeping and audit provisions of
               Article 9 of the License Agreement.

          1.6  Licensor will promptly upon request by Licensee transfer all
               knowhow and technical information necessary for the manufacturing
               of Licensed Products to Licensee in order to allow Licensee to
               manufacture such Licensed Products for commercial sale.
<PAGE>

          1.7  Licensee shall have the option, exercisable upon reasonable
               notice at any time following completion of Phase III clinical
               trials, to contract with Licensor to manufacture Licensed
               Products as a second source (or, if Licensee so determines,
               primary source) contract manufacturer for Licensee, and in either
               case, the supply agreement between Licensee and Licensor shall be
               upon and subject to the basic agreed terms for a Supply Agreement
               set forth in Section and Exhibit 17.2 of the License Agreement,
               except that (a) the parties shall be reversed and (b) Licensor's
               Cost for purposes of calculating the price of the Licensed
               Products shall not include any direct or indirect components
               (including amortized capital costs) representing amounts paid for
               by Licensee pursuant to Sections 1.3 - 1.5 of this Letter
               Agreement.

          1.8  In the event Licensor receives any notice, communication,
               memorandum or other correspondence from any governmental agency
               or authority (including the FDA) concerning the Licensed
               Products, including any correspondence relating to the facilities
               of Licensor used to manufacture the Licensed Products, Licensor
               shall provide a copy of same to Licensee immediately upon
               receipt.  In addition, Licensor shall give Licensee  immediate
               notice of any inspection, investigation or review of Licensor's
               premises or operations by any governmental agency or authority
               concerning the Licensed Products.  Licensor shall take all
               reasonable action necessary to afford Licensee the opportunity to
               participate in any such inspection, investigation or review.

     2.   The Research and Development Plan and the Budget originally adopted
          pursuant to the License Agreement are hereby amended to reflect the
          matters covered in this letter agreement and to reflect the attached
          Strategic Development Package Budget.  The Research and Development
          Plan and the Budget shall be further amended as contemplated by the
          License Agreement no later than January 31, 2001.

     3.   On or before January 31, 2001, the Steering Committee shall adopt an
          updated Market Projection Plan.
<PAGE>

Except as specifically amended by this Letter Agreement, the terms and
conditions of the License Agreement shall remain in full force and effect.  If
this letter accurately reflects your understanding of the modifications we have
agreed to, please so indicate by signing the enclosed copy of this Letter
Agreement and returning it to us.

                                    Very truly yours,
                                    CONTROL DELIVERY SYSTEMS, INC.



                                    By:  /s/ Paul Ashton
                                         ---------------------------

Read and Agreed:

BAUSCH & LOMB INCORPORATED


By:  /s/ Illegible
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