<PAGE>
--------------------------------------------------------------------------------
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                                 UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON D.C. 20549

                            ------------------------

                                   FORM 10-Q

<TABLE>
<C>        <S>
   /X/     QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
           SECURITIES EXCHANGE ACT OF 1934
</TABLE>

               FOR THE QUARTERLY PERIOD ENDED SEPTEMBER 30, 2000
                                       OR

<TABLE>
<C>        <S>
   / /     TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE
           SECURITIES EXCHANGE ACT OF 1934
</TABLE>

        FOR THE TRANSITION PERIOD FROM ______________ TO ______________

                         COMMISSION FILE NUMBER 0-18554

                            ------------------------

                       GENZYME DEVELOPMENT PARTNERS, L.P.

             (Exact name of registrant as specified in its charter)

<TABLE>
<S>                                            <C>
               DELAWARE                                     04-3065192
    (State or other jurisdiction of            (I.R.S. Employer Identification No.)
    incorporation or organization)

          ONE KENDALL SQUARE,                               02139-1562
       CAMBRIDGE, MASSACHUSETTS                             (zip code)
    (Address of principal executive
               offices)
</TABLE>

                                 (617) 252-7500
              (Registrant's telephone number, including area code)

                            ------------------------

    Indicate by check mark whether the registrant (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days. Yes /X/  No / /

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
<PAGE>
NOTE REGARDING REFERENCES

    Throughout this report, the words "we", "us" and "our" refer to Genzyme
Development Partners, L.P. In addition, we refer to:

    - Genzyme Corporation as "Genzyme;"

    - Genzyme Development Corporation II as "our general partner;" and

    - Genzyme Ventures II, our joint venture with Genzyme, as "our joint
      venture."

NOTE REGARDING FORWARD-LOOKING STATEMENTS

    This Form 10-Q contains forward-looking statements, including statements
concerning our:

    - Genzyme's intention to exercise its rights to purchase the outstanding
      limited partnership interests and to pay the purchase price using cash;

    - expected future revenues, operations and expenditures; and

    - the intention of Genzyme to fund our general and administrative expenses,
      and research and development programs.

These forward-looking statements represent the expectations of our general
partner as of the filing date of this Form 10-Q. Our actual results could differ
materially from those anticipated by the forward-looking statements due to a
number of factors, including:

    - whether Genzyme exercises its rights to purchase the outstanding limited
      partnership interests before the option expires and actually uses cash to
      pay the purchase price;

    - our ability to successfully complete preclinical and clinical development
      and obtain timely regulatory approval for our products;

    - our ability to obtain and maintain adequate patent and other proprietary
      rights protection for our products;

    - the content and timing of decisions made by the United States Food and
      Drug Administration and other agencies regarding our products and the
      indications for which our products may be approved;

    - the actual size and charecteristics of markets to be addressed by our
      products;

    - market acceptance of our products;

    - the ability of Genzyme to successfully commercialize the Sepra products in
      the United States and Canada on behalf of our joint venture;

    - the amount of royalty revenue received on European sales of the Sepra
      products by Genzyme;

    - Genzyme's ability to obtain reimbursement for our products;

    - the accuracy of our information concerning the products and resources of
      competitors and potential competitors;

    - funding of our general and administrative expenses and continued funding
      of our research and development programs by Genzyme; and

    - the risks and uncertainties described under the caption "Factors Affecting
      Future Operating Results" under Item 7., "Management's Discussion and
      Analysis of Financial Condition and Results of Operations" in our annual
      report on Form 10-K for the fiscal year ended December 31, 1999 (our "1999
      Form 10-K").

                                       2
<PAGE>
NOTE REGARDING INCORPORATION BY REFERENCE

    The Securities and Exchange Commission allows us to disclose important
information to you by referring you to other documents that we have filed with
the SEC. The information that we refer you to is "incorporated by reference"
into this report. Please read that information.

NOTE REGARDING TRADEMARKS

    Genzyme-Registered Trademark- and Sepra Film-Registered Trademark- are
registered trademarks of Genzyme. Sepramesh-TM- is a trademark of Genzyme.
Genzyme(SM) is a service mark of Genzyme.

                                       3
<PAGE>
                       GENZYME DEVELOPMENT PARTNERS, L.P.
                         FORM 10-Q, SEPTEMBER 30, 2000
                               TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                                          PAGE
                                                                        --------
<S>       <C>                                                           <C>
PART I.   FINANCIAL INFORMATION

ITEM 1.   Financial Statements:

          Unaudited Statements of Operations for the Three and Nine
            Months Ended September 30, 2000 and 1999..................      5

          Balance Sheets as of September 30, 2000 (unaudited) and
            December 31, 1999.........................................      6

          Unaudited Statements of Cash Flows for the Nine Months Ended
            September 30, 2000 and 1999...............................      7

          Notes to Unaudited Financial Statements.....................      8

ITEM 2.   Management's Discussion and Analysis of Financial Condition
            and Results of Operations.................................     11

ITEM 3.   Quantitative and Qualitative Disclosures About Market
            Risk......................................................     13

PART II.  OTHER INFORMATION

ITEM 6.   Exhibits and Reports on Form 8-K............................     14

Signatures............................................................     15
</TABLE>

                                       4
<PAGE>
PART I.  FINANCIAL INFORMATION

ITEM 1.  FINANCIAL STATEMENTS

                       GENZYME DEVELOPMENT PARTNERS, L.P.
                            STATEMENTS OF OPERATIONS
             (UNAUDITED, AMOUNTS IN THOUSANDS EXCEPT PER UNIT DATA)

<TABLE>
<CAPTION>
                                                             THREE MONTHS ENDED           NINE MONTHS ENDED
                                                                SEPTEMBER 30,               SEPTEMBER 30,
                                                          -------------------------   -------------------------
                                                            2000             1999       2000             1999
                                                          --------         --------   --------         --------
<S>                                                       <C>              <C>        <C>              <C>
Royalty revenue from Genzyme............................   $   58            $ 41      $  180            $133
Costs and expenses:
  Administrative expenses...............................       25              20          77              66
                                                           ------            ----      ------            ----
Operating income........................................       33              21         103              67
Other income:
  Equity in net income of joint venture (Note C)........      281              --         281              --
  Investment income.....................................        3               2           5               4
                                                           ------            ----      ------            ----
    Total other income..................................      284               2         286               4
                                                           ------            ----      ------            ----
Net income..............................................   $  317            $ 23      $  389            $ 71
                                                           ======            ====      ======            ====
Net income attributable to each partnership unit:
  Limited partners--based on 737 units..................   $  426            $ 31      $  523            $ 96
                                                           ======            ====      ======            ====
General partner--based on 1 unit........................   $3,168            $230      $3,891            $710
                                                           ======            ====      ======            ====
</TABLE>

    The accompanying notes are an integral part of these unaudited financial
                                  statements.

                                       5
<PAGE>
                       GENZYME DEVELOPMENT PARTNERS, L.P.
                                 BALANCE SHEETS
                             (AMOUNTS IN THOUSANDS)

<TABLE>
<CAPTION>
                                                              SEPTEMBER 30,   DECEMBER 31,
                                                                  2000            1999
                                                              -------------   ------------
                                                               (UNAUDITED)
<S>                                                           <C>             <C>
                           ASSETS
Cash and cash equivalents...................................      $  59           $  18
Royalty receivable from Genzyme.............................         57              59
Investment in joint venture (Note C)........................        281              --
                                                                  -----           -----
      Total assets..........................................      $ 397           $  77
                                                                  =====           =====
        LIABILITIES AND PARTNERS' CAPITAL (DEFICIT)
Accrued expenses............................................      $  66           $  70
Payable to Genzyme..........................................         42             107
                                                                  -----           -----
      Total liabilities.....................................        108             177
                                                                  -----           -----
Commitments and contingencies...............................         --              --

Partners' capital (deficit) (including accumulated deficit
  of $33,862 as of September 30, 2000):
  General partner...........................................       (214)           (218)
  Class A limited partners..................................        502             118
  Class B limited partners..................................          1              --
                                                                  -----           -----
      Total partners' capital (deficit).....................        289            (100)
                                                                  -----           -----
      Total liabilities and partners' capital (deficit).....      $ 397           $  77
                                                                  =====           =====
</TABLE>

    The accompanying notes are an integral part of these unaudited financial
                                  statements.

                                       6
<PAGE>
                       GENZYME DEVELOPMENT PARTNERS, L.P.
                            STATEMENTS OF CASH FLOWS
                       (UNAUDITED, AMOUNTS IN THOUSANDS)

<TABLE>
<CAPTION>
                                                                  NINE MONTHS ENDED
                                                                    SEPTEMBER 30,
                                                              -------------------------
                                                                2000             1999
                                                              --------         --------
<S>                                                           <C>              <C>
Cash flows from operating activities:
  Net income................................................   $ 389            $  71
  Reconciliation of net income to net cash provided by (used
    in) operating activities:
    Equity in net income of joint venture...................    (281)              --
    Increase (decrease) in cash from working capital:
      Royalties receivable from Genzyme.....................       2               47
      Payable to Genzyme and accrued expenses...............     (69)            (154)
                                                               -----            -----
  Net cash provided by (used in) operating activities.......      41              (36)
                                                               -----            -----
Increase (decrease) in cash and cash equivalents............      41              (36)
Cash and cash equivalents at beginning of period............      18               97
                                                               -----            -----
Cash and cash equivalents at end of period..................   $  59            $  61
                                                               =====            =====
</TABLE>

    The accompanying notes are an integral part of these unaudited financial
                                  statements.

                                       7
<PAGE>
                       GENZYME DEVELOPMENT PARTNERS, L.P.

               NOTES TO UNAUDITED CONDENSED FINANCIAL STATEMENTS

                               SEPTEMBER 30, 2000

A.  BASIS FOR PRESENTATION

    We were formed in 1989 to develop, produce and derive income from the sale
of products that we refer to as the Sepra products in the United States and
Canada. The Sepra products are, generally, products that:

    - are based in whole or in part on hyaluronic acid, which is a naturally
      occurring substance that protects tissue and organs;

    - are used in human clinical trials or human surgical procedures (other than
      ophthalmic surgery); and

    - have the effect of reducing the incidence or severity of adhesions (scar
      tissue).

    In August 1996, Genzyme received marketing approval from the FDA for our
first product, Sepra Film-Registered Trademark- bioresorbable membrane, and
commenced commercial sales of Sepra Film-Registered Trademark- bioresorbable
membrane in the United States on behalf of our joint venture. In March 2000,
Genzyme received FDA approval of Sepramesh-TM- biosurgical composite for use in
hernia repair procedures and commenced commercial sales of this product in
June 2000 in the United States on behalf of our joint venture.

    Per partnership unit information is based on the number of partnership units
outstanding at the end of each period. The number of units outstanding has not
changed since the date of our capitalization.

    We prepared our unaudited financial statements following the requirements of
the SEC for interim reporting. As permitted under those rules, certain notes or
other financial information that is normally required by generally accepted
accounting principles have been condensed or omitted.

    These financial statements are unaudited but include all normal and
recurring adjustments that we consider necessary for the fair presentation of
our financial position and operating results. Since these are interim financial
statements, you should also read the information, financial statements and
footnotes included in our 1999 Form 10-K. Revenues, expenses, assets and
liabilities can vary from quarter to quarter. Therefore, the results and trends
in these interim financial statements may not be indicative of the results for
the full year.

B.  DEVELOPMENT AGREEMENT

    Our Development Agreement calls for Genzyme to develop the Sepra products to
be used as surgical aids to limit the incidence and severity of postoperative
adhesions. We were required to reimburse Genzyme for all direct costs, a
reasonable allocation of indirect costs as they relate to the development effort
and a 10% management fee, up to our available funds. We paid a non-refundable
retainer fee of $1.5 million to Genzyme when our partnership commenced. Our
general partner has the authority to terminate the research program at any time
if it is deemed to be unfeasible or uneconomical. Genzyme has no obligation to
fund the programs beyond our available funds but has done so after we expended
our available funds in the first quarter of 1994. Genzyme has spent the
following amounts on our development programs since the first quarter of 1994:

    - $4.6 million for the nine months ended September 30, 2000 (unaudited);

    - $9.0 million in 1999;

    - $8.4 million in 1998;

    - $7.3 million in 1997;

                                       8
<PAGE>
                       GENZYME DEVELOPMENT PARTNERS, L.P.

         NOTES TO UNAUDITED CONDENSED FINANCIAL STATEMENTS (CONTINUED)

                               SEPTEMBER 30, 2000

    - $6.0 million in 1996;

    - $6.4 million in 1995; and

    - $6.5 million for the period April 1, 1994 through December 31, 1994.

    We are not obligated to reimburse Genzyme for any of these development
expenses. Genzyme currently intends to fund our development programs through
2000 on a level consistent with the 2000 budget for the programs.

C.  JOINT VENTURE AGREEMENT

    We formed our joint venture with Genzyme to make and sell Sepra products in
the United States and Canada. Genzyme manufactures the Sepra products and has
the exclusive right to sell the Sepra products in the United States and Canada
on behalf of our joint venture. Genzyme currently funds the joint venture's cash
needs. Once annual revenues from sales in the United States and Canada exceed
$25 million, Genzyme will be reimbursed for general and administrative support
through a quarterly commission equal to 10% of its revenues for each quarter.

    The first $5.6 million of net profits of our joint venture will be allocated
to us, and the next $8.4 million will be allocated to Genzyme. Afterward, 60% of
the net profits will be allocated to Genzyme and 40% to us.

    The first $200,000 of the joint venture's losses were allocated to us and,
thereafter, the losses are allocated 40% to us and 60% to Genzyme, except to the
extent that losses allocable to us would result in the allocation of these
losses to our general partner as a result of our limited partners' capital
account balance having been previously reduced to zero. In such an event, 100%
of the losses which would have been allocated to our general partner are
allocated to Genzyme. For financial statement purposes, Genzyme consolidates
100% of the losses of our joint venture funded by Genzyme's non-interest bearing
loans or capital contributions.

    Profits and losses of our joint venture are allocated on a year-to-date
basis. For the three months ended September 30, 2000, our joint venture earned
net income $365,000 and for the nine months ended September 30, 2000, our joint
venture earned net income of $281,000. Pursuant to the terms of the Amended and
Restated Joint Venture Agreement, the year-to-date net income of our joint
venture as of September 30, 2000 of $281,000 was allocated 100% to us. Losses
were not allocated to us from the joint venture for the three and nine months
ended September 30, 1999 because our basis in the joint venture was zero in each
of these periods and we are not eligible to receive loss allocation in excess of
our capital contributions to the joint venture.

                                       9
<PAGE>
                       GENZYME DEVELOPMENT PARTNERS, L.P.

         NOTES TO UNAUDITED CONDENSED FINANCIAL STATEMENTS (CONTINUED)

                               SEPTEMBER 30, 2000

    We have summarized condensed financial information of our joint venture in
the tables below:

<TABLE>
<CAPTION>
                                   THREE MONTHS ENDED                        NINE MONTHS ENDED
                                      SEPTEMBER 30,         INCREASE/          SEPTEMBER 30,         INCREASE/
                                -------------------------   (DECREASE)   -------------------------   (DECREASE)
                                  2000             1999      % CHANGE      2000             1999      % CHANGE
                                --------         --------   ----------   --------         --------   ----------
                                           (UNAUDITED, AMOUNTS IN THOUSANDS EXCEPT PERCENTAGE DATA)
<S>                             <C>              <C>        <C>          <C>              <C>        <C>
Revenues......................  $ 2,527          $ 1,692        49%      $ 6,437          $ 4,848         33%
Gross margin..................    1,819              947        92%        4,511            2,710         66%
Operating expenses............   (1,454)          (1,301)       12%       (4,230)          (3,670)        15%
Net income (loss).............      365             (354)      203%          281             (960)      (129%)
</TABLE>

<TABLE>
<CAPTION>
                                                                    AS OF                AS OF
                                                              SEPTEMBER 30, 2000   DECEMBER 31, 1999
                                                              ------------------   -----------------
                                                                 (UNAUDITED)
                                                                      (AMOUNTS IN THOUSANDS)
<S>                                                           <C>                  <C>
Current assets..............................................          $21                 $21
Noncurrent assets...........................................           --                  --
Current liabilities.........................................           21                  21
Noncurrent liabilities......................................           --                  --
</TABLE>

                                       10
<PAGE>
                       GENZYME DEVELOPMENT PARTNERS, L.P.

                         FORM 10-Q, SEPTEMBER 30, 2000

ITEM 2.  MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS
         OF OPERATIONS

INTRODUCTION

    The following discussion is a summary of the key factors the management of
our general partner considers necessary in reviewing our results of operations,
liquidity and capital resources.

RESULTS OF OPERATIONS

<TABLE>
<CAPTION>
                                                    THREE MONTHS                          NINE MONTHS
                                                       ENDED                                 ENDED
                                                   SEPTEMBER 30,        INCREASE/        SEPTEMBER 30,        INCREASE/
                                               ----------------------   (DECREASE)   ----------------------   (DECREASE)
                                                 2000          1999      % CHANGE      2000          1999      % CHANGE
                                               --------      --------   ----------   --------      --------   ----------
                                                       (UNAUDITED, AMOUNTS IN THOUSANDS, EXCEPT PERCENTAGE DATA)
<S>                                            <C>           <C>        <C>          <C>           <C>        <C>
Royalty revenue from Genzyme.................    $ 58          $41            41%      $180          $133          35%
Costs and expenses:
  Administrative expenses....................      25           20            25%        77            66          17%
                                                 ----          ---                     ----          ----
Operating income.............................      33           21            57%       103            67          54%
                                                 ----          ---                     ----          ----
Other income:
  Equity in net income of joint venture......     281           --           100%       281            --         100%
  Investment income..........................       3            2            50%         5             4          25%
                                                 ----          ---                     ----          ----
      Total other income.....................     284            2        14,100%       286             4       7,050%
                                                 ----          ---                     ----          ----
Net income...................................    $317          $23         1,278%      $389          $ 71         448%
                                                 ====          ===                     ====          ====
</TABLE>

ROYALTY REVENUE

    Under our Cross License Agreement with Genzyme, we record royalty revenue
upon the shipment and passage of title of the Sepra products by Genzyme to third
parties in Europe. Our royalties are calculated based on 6% of Genzyme's net
sales of the Sepra products in this region. Royalty revenue increased in the
three and nine months ended September 30, 2000 as compared to the same periods
of 1999 due primarily to increased sales of the Sepra products in Europe.

EQUITY IN NET INCOME OF JOINT VENTURE

    The first $5.6 million of net profits of our joint venture will be allocated
to us, and the next $8.4 million will be allocated to Genzyme. Afterward, 60% of
the net profits will be allocated to Genzyme and 40% to us.

    The first $200,000 of the joint venture's losses were allocated to us and,
thereafter, the losses are allocated 40% to us and 60% to Genzyme, except to the
extent that losses allocable to us would result in the allocation of these
losses to our general partner as a result of our limited partners' capital
account balance having been previously reduced to zero. In such an event, 100%
of the losses which would have been allocated to our general partner are
allocated to Genzyme. For financial statement purposes, Genzyme consolidated
100% of the losses of our joint venture funded by Genzyme's non-interest bearing
loans or capital contributions.

    Profits and losses of our joint venture are allocated on a year-to-date
basis. For the three months ended September 30, 2000, our joint venture earned
net income $365,000 and for the nine months

                                       11
<PAGE>
                       GENZYME DEVELOPMENT PARTNERS, L.P.

                         FORM 10-Q, SEPTEMBER 30, 2000

ended September 30, 2000, our joint venture earned net income of $281,000.
Pursuant to the terms of the Amended and Restated Joint Venture Agreement, the
year-to-date net income of our joint venture as of September 30, 2000 of
$281,000 was allocated 100% to us. Losses were not allocated to us from the
joint venture for the three and nine months ended September 30, 1999 because our
basis in the joint venture was zero in each of these periods and we are not
eligible to receive loss allocation in excess of our capital contributions to
the joint venture.

    Our joint venture recorded net income of $365,000 for the three months ended
September 30, 2000 and $281,000 for the nine months ended September 30, 2000 as
compared to net losses of $354,000 and $960,000 for the same periods of 1999.
Our joint venture's net revenues increased to $2.5 million for the three months
ended September 30, 2000 and $6.4 million for the nine months ended
September 30, 2000 from $1.7 million and $4.8 million for the same periods of
1999. The increase in revenues in each period was due to increased sales of
Sepra Film-Registered Trademark- bioresorbable membrane and the commencement of
sales of Sepramesh-TM- biosurgical composite in the United States in June 2000
and in Canada in September 2000. Our joint venture's gross margin increased by
92% and 66% in the three and nine months ended September 30, 2000 as compared to
the same periods of 1999 due primarily to the increased sales volume of the
Sepra products. In the three and nine months ended September 30, 2000 our joint
venture's operating expenses, which consist solely of selling and marketing
expenses, increased by 12% and 15% as compared to the same periods of 1999. This
increase was due to increased costs associated with selling and marketing Sepra
Film-Registered Trademark- bioresorbable membrane in the United States and
Canada and additional selling and marketing expenses related to the introduction
of Sepramesh-TM- biosurgical composite in the United States and Canada.
Sepramesh-TM- biosurgical composite commenced sales in Europe in October 2000.

FINANCIAL CONDITION

    As of September 30, 2000, we had $59,000 in cash and cash equivalents, an
increase of $41,000 from December 31, 1999. The remaining cash balance is
reserved for general and administrative expenses. In the nine months ended
September 30, 2000, we received $179,000 of cash from the collection of
royalties from Genzyme and used $143,000 of cash to reimburse Genzyme for
expenses it paid on our behalf.

    Our future profitability is entirely dependent upon our joint venture's
sales of the Sepra products. Our joint venture commenced operations following
receipt of FDA marketing approval of Sepra Film-Registered Trademark-
bioresorbable membrane in August 1996. Sepra Film-Registered Trademark-
bioresorbable membrane was the first Sepra product to obtain FDA marketing
approval and was launched in the United States during the fourth quarter of
1996. Sepra Film-Registered Trademark- bioresorbable membrane is being marketed
in the United States and Canada by Genzyme on behalf of our joint venture. In
March 2000, Genzyme received FDA approval of Sepramesh-TM- biosurgical composite
for use in hernia repair procedures and commenced commercial sales of this
product in June 2000 in the United States on behalf of our joint venture. In
July 2000, Genzyme received approval of Sepramesh-TM- biosurgical composite for
use in Canada and Europe and commenced commercial sales in Canada in
September 2000 and in Europe in October 2000.

    We will require substantial additional funds to complete the development and
clinical testing of the Sepra products. Genzyme has funded the research and
development programs for our Sepra products on an annual basis since the first
quarter of 1994, when we depleted all of the funds we had available to develop
our products. Genzyme is obligated to provide this funding through 2000. There
is no guarantee that Genzyme will continue funding our program after 2000.
Genzyme has committed to fund our administrative expenses in excess of our cash
balance. Genzyme is not obligated to provide

                                       12
<PAGE>
                       GENZYME DEVELOPMENT PARTNERS, L.P.

                         FORM 10-Q, SEPTEMBER 30, 2000

such funding after 2000. If Genzyme stops funding our operations and development
programs, we cannot guarantee that we will be able to obtain any additional
financing or find it on favorable terms. If we have insufficient funds or are
unable to raise additional funds, we may delay, reduce or eliminate all or some
of our programs.

PARTNERSHIP PURCHASE OPTION AGREEMENT

    Under the Partnership Purchase Option Agreement, Genzyme has the option to
purchase our limited partnership interests during the 90-day period that began
on August 31, 2000. If Genzyme exercises the option, each of our limited
partners will receive approximately $35,000 per partnership unit, in cash,
Genzyme common stock, or any combination of the two. Additionally, our limited
partners would be eligible to receive quarterly royalty payments for a period of
ten years after the buyout date unless Genzyme prepays this royalty stream. This
option to purchase our limited partnership interests may no longer be exercised
after November 28, 2000. Genzyme has informed us that it currently expects that
it will exercise the purchase option during November and pay the approximately
$26 million option price in cash.

EURO--THE EUROPEAN CURRENCY

    Since December 31, 1999, there have been no material changes related to
Genzyme's outstanding derivatives and forward contracts, or any other material
contracts as a result of the euro conversion, nor have there been any material
changes in Genzyme's or our competitive position as a result of the conversion.
We incorporate our disclosure related to the euro conversion set forth under the
heading "Management's Discussion and Analysis of Financial Condition and Results
of Operations--Euro--the New European Currency" in our 1999 Form 10-K by
reference into this section.

ITEM 3.  QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

    Not applicable.

                                       13
<PAGE>
                       GENZYME DEVELOPMENT PARTNERS, L.P.

                         FORM 10-Q, SEPTEMBER 30, 2000

PART II. OTHER INFORMATION

ITEM 6. EXHIBITS AND REPORTS ON FORM 8-K

    (a) Exhibits

       27  Financial Data Schedule for Genzyme Development Partners, L.P. (for
           EDGAR filing purposes only). Filed with this report.

    (b) Reports on Form 8-K

       We did not file any reports on Form 8-K during the quarter ended
           September 30, 2000.

                                       14
<PAGE>
                       GENZYME DEVELOPMENT PARTNERS, L.P.
                         FORM 10-Q, SEPTEMBER 30, 2000

                                   SIGNATURES

    Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.

<TABLE>
<S>                                                    <C>  <C>
                                                       GENZYME DEVELOPMENT PARTNERS, L.P.
                                                       (REGISTRANT)

                                                       By:  GENZYME DEVELOPMENT CORPORATION II,
                                                            ITS GENERAL PARTNER

                                                       By:  /s/ MICHAEL S. WYZGA
                                                            -----------------------------------------
                                                            Michael S. Wyzga
Date: November 14, 2000                                     TREASURER AND CHIEF FINANCIAL OFFICER
</TABLE>

                                       15
<PAGE>
                       GENZYME DEVELOPMENT PARTNERS, L.P.
                         FORM 10-Q, SEPTEMBER 30, 2000

                                 EXHIBIT INDEX

<TABLE>
<CAPTION>
     EXHIBIT NO.                                DESCRIPTION
---------------------   ------------------------------------------------------------
<C>                     <S>
    27                  Financial Data Schedule for Genzyme Development Partners,
                        L.P. (for EDGAR filing purposes only). Filed with this
                        report.
</TABLE>

                                       16