<PAGE>

                      SECURITIES AND EXCHANGE COMMISSION
                             Washington, DC 20549

                                   Form 10-Q

                  QUARTERLY REPORT UNDER SECTION 13 OR 15 (d)
                    OF THE SECURITIES EXCHANGE ACT OF 1934


                       For Quarter Ended April 30, 2001
                                         --------------

                         Commission File Number 1-9579
                                                ------


                                  Ecogen Inc.
                                  -----------
            (Exact name of registrant as specified in its charter)



               Delaware                                    22-2487948
               --------                                    ----------
    (State or other jurisdiction of                     (I.R.S. Employer
    incorporation or organization)                   Identification Number)


    2000 W. Cabot Boulevard #170, Langhorne, Pennsylvania       19047
    -----------------------------------------------------       -----
           (Address of principal executive offices)           (Zip Code)



Registrant's telephone number,
including area code                               (2l5) 757-l590
                                                  --------------


     Indicate by check mark whether the registrant (l) has filed all reports
required to be filed by Section l3 or l5 (d) of the Securities Exchange Act of
l934 during the preceding l2 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 ___.
                                              ---

     Indicate the number of shares outstanding of each of the issuer's classes
of common stock, as of the latest practicable date:

          Class                       Outstanding at May 31, 2001
          -----                       ---------------------------

Common Stock, $.01 par value                   14,278,797
<PAGE>

                                 ECOGEN INC.
                                 -----------

                                    INDEX


<TABLE>
<CAPTION>
                                                                                          Page
                                                                                          ----
<S>                                                                                       <C>
PART I - FINANCIAL INFORMATION

  Item 1        - Financial Statements:


     Unaudited Consolidated Condensed Balance Sheets as of
         April 30, 2001 and October 31, 2000...........................................      1

     Unaudited Consolidated Condensed Statements of Operations
         for the three and six months ended April 30, 2001 and 2000....................      2

     Unaudited Consolidated Condensed Statement of Stockholders' Equity
         for the six months ended April 30, 2001.......................................      3

     Unaudited Consolidated Condensed Statements of Cash Flows
         for the six months ended April 30, 2001 and 2000..............................      4

     Notes to Unaudited Consolidated Condensed Financial
         Statements....................................................................      6



  Item 2        - Management's Discussion and Analysis of Results
                    of Operations and Financial Condition..............................     10



PART II - OTHER INFORMATION

  Item 6(a)     - Exhibits.............................................................     14
</TABLE>


<PAGE>



                         ECOGEN INC. AND SUBSIDIARIES

                UNAUDITED CONSOLIDATED CONDENSED BALANCE SHEETS

<TABLE>
<CAPTION>
---------------------------------------------------------------------------------------------------------------
Assets
                                                                              April 30,              October 31,
                                                                                 2001                   2000
---------------------------------------------------------------------------------------------------------------
<S>                                                                           <C>                     <C>
Current  assets:
   Cash and cash  equivalents                                               $     8,203            $   215,777
   Trade receivables, net                                                       678,361                616,741
   Inventory, net                                                             1,073,537              2,051,184
   Prepaid expenses and other current assets                                    434,882                284,673
---------------------------------------------------------------------------------------------------------------
      Total current assets                                                    2,194,983              3,168,375
---------------------------------------------------------------------------------------------------------------

Plant and equipment, net                                                        181,968                677,831
Other assets, net                                                             2,366,522              2,653,571
---------------------------------------------------------------------------------------------------------------
                                                                            $ 4,743,473            $ 6,499,777
===============================================================================================================

Liabilities and Stockholders' Deficit

---------------------------------------------------------------------------------------------------------------
Current liabilities:
   Debt due within one year                                                   2,688,103              2,123,972
   Accounts payable and accrued expenses                                      4,979,463              4,834,499
---------------------------------------------------------------------------------------------------------------
        Total current liabilities                                             7,667,566              6,958,471
---------------------------------------------------------------------------------------------------------------

---------------------------------------------------------------------------------------------------------------
Long-term debt                                                                        -                  9,306
---------------------------------------------------------------------------------------------------------------
Long-term deferred revenue                                                    1,696,928              1,612,928
---------------------------------------------------------------------------------------------------------------
Minority interest                                                             1,533,854              1,533,854
---------------------------------------------------------------------------------------------------------------

Stockholders' deficit:
   Preferred stock, par value $.01 per share; authorized 7,500,000 shares:
       Series 2000 A convertible preferred stock                                     66                     76
       Series 1998 C convertible preferred stock                                    324                    324
   Common stock, par value $.01 per share                                       142,788                134,925
   Additional paid-in capital                                               129,317,804            129,319,027
   Accumulated deficit                                                     (135,615,857)          (133,069,134)
---------------------------------------------------------------------------------------------------------------
        Total stockholders' deficit                                          (6,154,875)            (3,614,782)
---------------------------------------------------------------------------------------------------------------
                                                                           $  4,743,473           $  6,499,777
===============================================================================================================
</TABLE>

         See Accompanying Consolidated Condensed Financial Statements

                                       1
<PAGE>
                         ECOGEN INC. AND SUBSIDIARIES

           UNAUDITED CONSOLIDATED CONDENSED STATEMENTS OF OPERATIONS

<TABLE>
<CAPTION>
-----------------------------------------------------------------------------------------------------------------------------
                                                                  Three Months Ended                   Six Months Ended
                                                                      April 30,                           April 30,
                                                                2001              2000            2001               2000
-----------------------------------------------------------------------------------------------------------------------------
<S>                                                         <C>               <C>             <C>                <C>
Revenues:

  Product sales,  net                                          $805,357        $2,376,124      $1,597,850         $3,475,624
  Contract research                                             172,813                 -         172,813                  -
-----------------------------------------------------------------------------------------------------------------------------
    Total revenues                                              978,170         2,376,124       1,770,663          3,475,624
-----------------------------------------------------------------------------------------------------------------------------

Costs and expenses:

  Cost of products sold                                         801,166         1,991,860       1,487,439          2,898,390
  Research and development:                                     189,915           462,486         482,097            904,390
  Selling, general and administrative                         1,091,506         1,632,593       1,919,437          2,842,630
-----------------------------------------------------------------------------------------------------------------------------
    Total costs and expenses                                  2,082,587         4,086,939       3,888,973          6,645,410
-----------------------------------------------------------------------------------------------------------------------------
Operating loss                                               (1,104,417)       (1,710,815)     (2,118,310)        (3,169,786)
-----------------------------------------------------------------------------------------------------------------------------

Other income (expense):
    Interest expense, net                                      (199,135)         (226,750)       (321,775)          (372,997)
    Other income                                                124,095                 -         155,567             54,351
-----------------------------------------------------------------------------------------------------------------------------
    Total other expense, net                                    (75,040)         (226,750)       (166,208)          (318,646)
-----------------------------------------------------------------------------------------------------------------------------

Net loss                                                     (1,179,457)       (1,937,565)     (2,284,518)        (3,488,432)

Dividends on preferred stock including assumed
     incremental yield of $63,219 in 2000                       127,544           354,847         262,205            510,034
-----------------------------------------------------------------------------------------------------------------------------

Net loss allocable to common stockholders                   ($1,307,001)      ($2,292,412)    ($2,546,723)       ($3,998,466)
=============================================================================================================================

Basic and diluted net loss per common share                      ($0.09)           ($0.19)         ($0.18)            ($0.36)
=============================================================================================================================

Weighted average number of common
     shares outstanding                                      14,198,900        12,014,000      13,839,800         11,024,000
=============================================================================================================================
</TABLE>


See Accompanying Notes to Unaudited Consolidated Condensed Financial Statements

                                       2
<PAGE>

                         ECOGEN INC. AND SUBSIDIARIES

      UNAUDITED CONSOLIDATED CONDENSED STATEMENT OF STOCKHOLDERS' EQUITY
                        Six months ended April 30, 2001

<TABLE>
<CAPTION>
-----------------------------------------------------------------------------------------------------------------------------------
                                                        Convertible                    Additional
                                                         Preferred      Common          Paid-in      Accumulated
                                                           Stock         Stock          Capital        Deficit            Total
-----------------------------------------------------------------------------------------------------------------------------------
<S>                                                     <C>             <C>          <C>            <C>               <C>
Balance November 1, 2000                                       $400     $134,925     $129,319,027   ($133,069,134)    ($3,614,782)

Dividends on preferred stock                                      -          513            6,117        (262,205)       (255,575)

Conversion of 950 shares of Series 1999 A convertible
  preferred stock to 734,988 shares of common stock             (10)       7,350           (7,340)              -               -

Net loss                                                          -            -                -      (2,284,518)     (2,284,518)

-----------------------------------------------------------------------------------------------------------------------------------
Balance April 30, 2001                                         $390     $142,788     $129,317,804   ($135,615,857)    ($6,154,875)
===================================================================================================================================
</TABLE>

          See Accompanying Notes To Unaudited Consolidated Condensed
                            Financial Statements.

                                       3

<PAGE>


                         ECOGEN INC. AND SUBSIDIARIES

           UNAUDITED CONSOLIDATED CONDENSED STATEMENTS OF CASH FLOWS

<TABLE>
<CAPTION>
------------------------------------------------------------------------------------------------------------------

                                                                                        Six months ended
                                                                                           April 30,
                                                                                  2001                    2000
------------------------------------------------------------------------------------------------------------------
<S>                                                                         <C>                     <C>
Cash flows from operating activities:
   Net loss                                                                   ($2,284,518)            ($3,488,432)
   Adjustments to reconcile net loss to net
      cash used in operating activities:
         Depreciation and amortization expense                                    341,146                 348,249
         Gain on sale of assets                                                  (139,740)                      -
         Noncash interest and other expense                                       267,054                 171,327
         Changes in assets and liabilities                                      1,010,620                 909,380

------------------------------------------------------------------------------------------------------------------
Net cash used in operating activities                                            (805,438)             (2,059,476)
------------------------------------------------------------------------------------------------------------------

Cash flows from investing activities:
   Proceeds from sale of assets                                                   169,365                       -
   Purchase of plant and equipment                                                      -                 (44,978)
   Acquisition, net                                                                     -                (285,000)

------------------------------------------------------------------------------------------------------------------
Net cash used in investing activities                                             169,365                (329,978)
------------------------------------------------------------------------------------------------------------------

Cash flows from financing activities:
   Proceeds from bank loan                                                              -               1,500,000
   Proceeds from promissory notes                                               1,000,500                       -
   Payments on line of credit, net                                               (436,370)               (397,640)
   Repayment of capital lease obligations                                        (135,631)               (145,570)
   Proceeds from sale of convertible preferred stock, net of issuance costs             -               1,399,500
   Net proceeds from issuance of common stock under stock option plan                   -                  39,832

------------------------------------------------------------------------------------------------------------------
Net cash provided by financing activities                                         428,499               2,396,122
------------------------------------------------------------------------------------------------------------------

Net (decrease) increase in cash                                                  (207,574)                  6,668

Cash and cash equivalents, beginning of period                                    215,777                       -

------------------------------------------------------------------------------------------------------------------
Cash and cash equivalents, end of period                                    $       8,203           $       6,668
==================================================================================================================
</TABLE>

                                                                     (Continued)

                                       4
<PAGE>

                         ECOGEN INC. AND SUBSIDIARIES

     UNAUDITED CONSOLIDATED CONDENSED STATEMENTS OF CASH FLOWS, CONTINUED

<TABLE>
<CAPTION>
--------------------------------------------------------------------------------------------------------------
                                                                                  Six months ended
                                                                                      April 30,
                                                                               2001             2000
--------------------------------------------------------------------------------------------------------------
 <S>                                                                          <C>               <C>
 Changes in assets and liabilities, net of acquisition:
  Increase in receivables                                                     $  (61,620)        $ (701,772)
  Decrease in inventory                                                          977,647          1,292,447
  Decrease (increase) in prepaid expenses and
    other current assets                                                          99,791            (71,418)
  Decrease in other assets                                                        46,828            120,121
  (Decrease) increase in accounts payable
    and accrued expenses                                                         (52,026)           270,002

--------------------------------------------------------------------------------------------------------------
    Changes in assets and liabilities, net                                    $1,010,620         $  909,380
==============================================================================================================

--------------------------------------------------------------------------------------------------------------
Noncash investing and financing activities:
--------------------------------------------------------------------------------------------------------------
</TABLE>

During the first six months of fiscal 2001 and 2000, the Company issued 734,986
and 984,732 shares of its common stock, respectively, upon conversion of the
Company's convertible preferred stock and issued 51,289 and 52,356 shares of
common stock, respectively as dividends at the time of conversion.

During the first half of fiscal 2001, the Company transferred ownership of
certain fixed assets to a contract manufacturer in exchanged for $250,000 in
credits to be applied toward future costs of production at that facility.

In fiscal 2000, the Company issued 1,351,351 shares of its common stock in
connection with an acquisition.

In the first six months of fiscal 2000, the Company issued 20,000 shares of its
common stock as a fee in connection with the issuance of preferred stock and
issued warrants to purchase 200,000 shares of common stock in connection with a
loan agreement. In the first half of fiscal 2000, the Company issued 15,544
common shares pursuant to employee benefits plans.


     See Accompanying Notes to Unaudited Consolidated Condensed Financial
                                  Statements.

                                       5
<PAGE>

                         ECOGEN INC. AND SUBSIDIARIES

        Notes to Unaudited Consolidated Condensed Financial Statements

                            April 30, 2001 and 2000

(1) Basis of Presentation and Summary of Significant Accounting Policies
    --------------------------------------------------------------------

    Organization and Basis of Presentation:

    The consolidated condensed financial statements include the accounts of
    Ecogen Inc. ("Ecogen" or the "Company") and its wholly-owned and majority-
    owned subsidiaries.  All intercompany accounts and transactions have been
    eliminated in consolidation.

    The accompanying consolidated condensed financial statements include all
    adjustments (consisting of normal recurring accruals) which are, in the
    opinion of management, necessary for a fair presentation of the consolidated
    results of operations and financial position for the interim periods
    presented.  The consolidated condensed financial statements have been
    prepared in accordance with the requirements for Form 10-Q and, therefore,
    do not include all disclosures of financial information required by
    generally accepted accounting principles. These consolidated condensed
    financial statements should be read in conjunction with the Company's
    October 31, 2000 consolidated financial statements and notes thereto
    included in the Company's Annual Report on Form 10-K.

    The results of operations for the interim period ended April 30, 2001 are
    not necessarily indicative of the operating results for the full year.

    Operations:

    The Company is a biotechnology company specializing in the development and
    marketing of environmentally compatible products for the control of pests in
    agricultural and related markets. The Company has not yet achieved
    profitable operations for any of its fiscal years and there is no assurance
    that profitable operations, if achieved, could be sustained on a continuing
    basis. Further, the Company's future operations are dependent, among other
    things, on the success of the Company's commercialization efforts and market
    acceptance of the Company's products.

    Net Loss Per Common Share:

    Basic loss per share is based on net loss allocable to common stockholders
    for the relevant period, divided by the weighted average number of common
    shares outstanding during the period. Diluted loss per share is based on net
    loss allocable to common stockholders for the relevant period divided by
    common shares outstanding and other potential common shares if they are
    dilutive.

    Because the Company reported a net loss per share, there is no difference
    between the Company's basic and diluted net loss per share calculations,
    since all potential common shares were anti-dilutive.

                                                           (Continued)

                                       6
<PAGE>

                         ECOGEN INC. AND SUBSIDIARIES

   Notes to Unaudited Consolidated Condensed Financial Statements, Continued


(2)  Liquidity
     ---------

     The Company has reported net loses allocable to common stockholders of
     ($2.5) million and ($4.0) million for the six-month periods ended April 30,
     2001, and 2000, respectively. The loss from inception in 1983 to April 30,
     2001 amounted to ($135.6) million. Further, the Company has a working
     capital deficit, a stockholders' deficit and limited liquid resources.
     These factors raise substantial doubt about the Company's ability to
     continue as a going concern. The financial statements do not include any
     adjustments relating to the recoverability and classification of reported
     asset amounts or the amount or classification of liabilities, which might
     result from the outcome of this uncertainty.

     The Company's continued operations will depend on its ability to raise
     additional funds. The Company has financed its working capital needs
     primarily through private and public offerings of equity and debt
     securities, revenues from research and development alliances and product
     sales. In addition, the Company has a working capital line of credit, which
     originally expired in August 2000 but has been extended to June 29, 2001, a
     term loan of $1.5 million and promissory notes aggregating $1.0 million
     that are due on June 23, 2002. However, in the event that the Company
     receives net proceeds in excess of $50 thousand from non-operating activity
     prior to June 23, 2002, the holders of the term loan and the promissory
     notes may elect to require a prepayment of the balance due on the loan
     and/or the notes. The Company currently is not in compliance with the
     covenants of its working capital line of credit. This line of credit had a
     balance of $.2 million as of April 30, 2001 and a balance of $29 thousand
     at June 14, 2001. As a result of the Company's non-compliance with the
     covenants, the working capital lender has discontinued making loans and
     may, at its option, liquidate the collateral including inventory and
     accounts receivable.

     The Company continues to pursue the raising of additional funds and other
     strategic initiatives including the sale of all or certain assets to
     improve its working capital position and its capital structure. During
     fiscal 2001, the Company borrowed $1.0 million pursuant to promissory notes
     that were due on June 30, 2001 and have been extended to June 23, 2002. The
     holder of the notes is a corporation controlled by one of the Company's
     principal stockholders. Further the Company has taken a number of steps,
     including personnel reductions, to conserve cash until it is it is able to
     sell assets. The Company needs to obtain proceeds from the sale of assets
     by to provide the necessary cash resources to repay the outstanding
     balances under its line of credit, its term loan and promissory notes, its
     accounts payable and fund operations. Further, the Company needs to
     continue to obtain short-term financing while it negotiates its strategic
     transactions. At this time the Company is unable to predict whether it will
     be successful in its efforts. If the Company is not successful in obtaining
     additional funding or selling assets, the Company will not be able to
     continue as a going concern. Over the long-term, the Company's liquidity is
     dependent on market acceptance of its products and technology.

(3)  Inventory
     ---------

     At April 30, 2001, inventory consisted of raw materials of $.4 million,
     work-in-progress of $.2 million and finished products of $.5 million.

                                                            (Continued)


                                       7
<PAGE>

                         ECOGEN INC. AND SUBSIDIARIES

   Notes to Unaudited Consolidated Condensed Financial Statements, Continued


(4)  Debt Agreements
     ---------------

     In August 1998, the Company obtained a secured, revolving working capital
     line of credit for up to $5.0 million with a financial institution. The
     working capital line of credit expired in August 2000 (but has been
     extended to June 29,2001), bears interest at prime plus 3.25% and is fully
     collateralized by the Company's assets, other than certain of its
     intellectual property rights. At April 30, 2001, the balance outstanding
     under the line was $.2 million. At June 14, 2001, the balance was $29
     thousand. The loan agreement contains certain financial covenants and has
     certain restrictions on the Company's ability to pay dividends on its
     common stock. The Company is not in compliance with such covenants. As a
     result of the Company's non-compliance, the lender has discontinued making
     loans and may, at its option, liquidate the collateral.

     On December 24, 1999, the Company obtained a secured loan for $1.5 million
     with a financial institution that is controlled by a principal stockholder
     of the Company. The loan required a $.5 million principal payment in June
     2000 (which was extended to June 2001) with the balance due in June 2001.
     Recently, the loan has been extended to June 23, 2002. However, in the
     event that the Company receives net proceeds in excess of $50 thousand from
     non-operating activity prior to June 23, 2002, the holder of the term loan
     may elect to require a prepayment of the balance due under the loan. The
     loan bears interest at prime plus 2% and is payable monthly. The Company's
     assets collateralize the loan. A corporation controlled by one of the
     Company's principal stockholders guarantees the loan. In connection with
     the guarantee, the corporation was issued a five-year warrant to purchase
     200,000 shares of the Company's common stock at $1.25 per share. The value
     of such warrants of $183,556 was recorded as deferred debt expense and
     amortized as interest expense over the life of the loan.

     During fiscal 2001, a corporation controlled by one of the Company's
     principal stockholders loaned the Company $1.0 million pursuant to
     promissory notes that were due June 30,2001, bear interest at 12%, and are
     secured by an interest in any success fees received under the Company's
     agreement with Monsanto Company. The due date on such notes has been
     extended to June 23, 2002. However, in the event that the Company receives
     net proceeds in excess of $50 thousand from non-operating activity prior to
     June 23, 2002, the holder of the promissory notes may elect to require a
     prepayment of the balance due on the notes.

(5)  Stockholders' Equity
     --------------------

     During fiscal 2001, the Company issued 734,988 shares of its common stock
     in exchange for 950 shares of the Company's Series 2000-A 7% convertible
     preferred stock issued in February 2000. The Company also issued 51,289
     shares of its common stock in payment of cumulative dividends at the time
     of conversion.

(6)  Plant and Equipment
     -------------------

     During the first quarter of fiscal 2001, the Company transferred ownership
     in certain fixed assets to a contract manufacturer of the Company in
     exchange for $.3 million in credits to be used for future costs of
     production at that facility. If at the end of two years the Company has not
     utilized the full amount of the credits for production, the balance due
     will be paid to the Company in cash. The credits have been recorded as
     prepaid expenses and other assets.


                                        (Continued)

                                       8
<PAGE>

                         ECOGEN INC. AND SUBSIDIARIES

   Notes to Unaudited Consolidated Condensed Financial Statements, Continued


(7)  Acquisition
     -----------

     On February 15, 2000, the Company completed its acquisition of certain
     assets of the sprayable Bt bioinsecticide business of Mycogen Corporation,
     an affiliate of Dow AgroSciences LLC. The Company issued 1,351,351 shares
     of the Company's common stock valued at approximately $3.0 million upon the
     closing of the transaction. Prior to the closing, the Company acquired
     approximately $.4 million of Mycogen's inventory of sprayable Bt products,
     under a distribution agreement effective January 31, 2000. Under the terms
     of the agreement, Mycogen has agreed to hold the shares for a three-year
     period, except in the event of certain change in control transactions.
     Mycogen was granted certain demand and piggyback registration rights with
     respect to the shares. In addition, Mycogen has the right of first refusal
     to purchase securities of the Company so as to maintain its ownership
     percentage in the Company. Mycogen also has been granted certain market
     price protection rights at the time that Mycogen sells the shares, which
     may result in the issuance of additional shares, which may not exceed 20%
     of the Company's outstanding shares without stockholder approval. The
     Company and Dow AgroSciences LLC also entered into a five-year supply
     agreement and the companies have entered into distribution agreements
     granting exclusive rights to Dow AgroSciences to sell the acquired products
     in Mexico, New Zealand, Australia and France.

     The transaction was accounted for as a purchase and, accordingly, the total
     purchase price for the assets of approximately $3.4 million, including out
     of pocket expenses, was allocated based upon their fair value at the date
     of acquisition. The assets acquired include inventory and certain
     identifiable intangible assets including a license to certain genes and
     strains and product registration and data citation rights. Included in the
     purchase price is inventory acquired by the Company prior to the final
     closing under a distribution agreement. The agreement also provides that
     the Company has no obligation for past or future royalties under a 1998
     settlement agreement with Mycogen on a patent infringement dispute. Under
     purchase accounting, part of the purchase price has been allocated to other
     assets for the fully paid up royalty and any amounts previously accrued
     under the settlement agreement have been eliminated in purchase accounting.

     The following unaudited pro forma information has been prepared as if the
     February 2000 acquisition of the products had occurred on November 1, 1999.
     The unaudited pro forma information does not purport to represent the
     Company's consolidated results of operations that would have been achieved
     had the transaction to which pro forma effect is given been consummated as
     the date or period indicated.

                                              Six Months Ended April 30,
                                                   2001          2000
                                                   ----          ----
                                        ($ in thousands except per share data)

          Total revenues                           $ 1,720     $ 4,251
          Net loss allocable to
             common stockholders                    (2,546)     (4,215)
          Basic and diluted net
             loss per share                           (.18)       (.34)

                                       9
<PAGE>

                         ECOGEN INC. AND SUBSIDIARIES

                    Management's Discussion and Analysis of
                 Results of Operations and Financial Condition

           Three Months and Six Months Ended April 30, 2001 and 2000

SIX MONTHS ENDED APRIL 30, 2001 AND 2000
----------------------------------------

Revenues
--------

Net product sales were $1.6 million and $3.5 million for the first six months of
fiscal 2001 and 2000, respectively, representing a decrease of 54%. Sales of the
Company's Bt product line, representing 92% of Company's product sales in the
first six months of fiscal 2001, decreased 49%. Biofungicide product sales,
which represented 9% of product sales in fiscal 2001, decreased $.2 million from
the year-ago period. Other product sales, representing 9% of Company's product
sales, decreased $.2 million in the first half of fiscal 2001 when compared to
the comparable quarter in fiscal 2000. The decrease in product sales were
primarily the result of the Company's limited ability to fund production and the
purchase of finished goods from Dow AgroSciences LLC. due to the Company's
limited liquid resources.

Contract research revenues increased $.2 million due to grants funded in fiscal
2001.

Costs and Expenses
------------------

Cost of products sold decreased 49% in the first six months of fiscal 2001
compared to the same period in fiscal 2000. Gross margins on product sales were
7% for fiscal 2001 and 17% in fiscal 2000. The lower gross margins in fiscal
2001 were principally due to unabsorbed overhead due to limited production.

Total operating expenses were $2.4 million in the first six months of fiscal
2001, compared to $3.7 million in fiscal 2000, a decrease of 36% due to cost
reduction measures implemented by the Company in fiscal 2001 to conserve cash,
including personnel reductions. Research and development costs decreased $.4
million or 47% and selling, general and administrative expenses decrease $.9
million or 32% in the first half of fiscal 2001.

Operating loss was ($2.3) million in the first six months of fiscal 2001
compared to 3.5 million in 2000 due principally to lower operating expenses in
fiscal 2001.

Other expense, net, decreased $.2 million in the first six months of fiscal 2001
compared to the same period in fiscal 2000 due primarily to gains on the sale of
assets.

Net Loss
--------

Net loss allocable to common stockholders for the six months ended April 30,
2001 were ($2.5) million, compared to a net loss allocable to common
stockholders of ($4.0) million for the same period in fiscal 2000 substantially
as a result of lower expenses. Basic and diluted net loss per share for the six
months ended April 30, 2001 was ($.18), compared to net loss per share of ($.36)
in fiscal 2000 on weighted average shares outstanding of 13.8 million and 11.0
million in the first six months of fiscal 2001 and 2000, respectively.

                                       10
<PAGE>

THREE MONTHS ENDED APRIL 30, 2001 AND 2000
------------------------------------------

Revenues
--------

During the three months ended April 30,2001, net product sales decreased $1.6
million or 66% principally due to volume. Sales of the Company's Bt product
line, representing 96% of the Company's product sales, decreased 62% in fiscal
2001. The decrease in Bt product sales was primarily the result of the Company's
limited ability to fund production and the purchase of finished goods from Dow
AgroSciences LLC. due to the Company's limited liquid resources. Biofungicide
and other product sales have been substantially discontinued during the second
quarter of fiscal 2001.

Contract research revenues increased $.2 million due to grants funded in the
second quarter of fiscal 2001.


Costs and Expenses
------------------

Cost of products sold decreased 60% in the first three months of fiscal 2001
compared to the same period in fiscal 2000 due primarily to a decrease in
product sales. Gross margins on product sales declined from 17% in fiscal 2000
to 7% in fiscal 2001. The lower gross margins on product sales in the second
quarter of fiscal 2001 were due principally to unapplied overhead as a result of
limited production.

Total operating expenses, consisting of research and development and selling,
general and administrative expenses, were $1.3 million in the second quarter of
fiscal 2001, compared to $2.1 million in the comparable period in fiscal 2000.
This 39% decrease was due to cost reduction measures implemented by the Company
to conserve cash, including personnel reductions. Further cost reduction have
been implemented in operating expenses subsequent to the end of the second
quarter of fiscal 2001. Research and development costs decreased $.3 million or
60% and selling, general and administrative expenses decreased $.5 million or
33% in the second quarter of fiscal 2001 compared to fiscal 2000.

The operating loss improved from ($1.7) million in the second quarter of fiscal
2000 to ($1.1) million in the comparable period in fiscal 2001. The improvement
was primarily due to the decrease in operating expenses.

Net Loss
--------

Net loss allocable to common stockholders for the three months ended April 30,
2001 was ($1.3) million, compared to a net loss allocable to common stockholders
of ($2.3) million for the same period in fiscal 2000. Basic and diluted net loss
per share for the three months ended April 30, 2001 was ($.09), compared to net
loss per share of ($.19) in the comparable period of fiscal 2000 on weighted
average shares outstanding of 14.2 million and 12.0 million in the three months
ended April 30, 2001 and 2000, respectively. Net loss allocable to common
stockholders included preferred stock dividends of $.1 million and $.3 million
in the second quarter of fiscal 2001 and 2000, respectively, including an
assumed incremental yield of $.1 million in fiscal 2000.

                                       11
<PAGE>

Seasonality of Business
-----------------------

The bulk of the Company's current products are presently marketed for
agricultural applications in the northern hemisphere, where the growing season
generally runs from spring through fall. Because of the seasonal nature of its
business, the Company's product revenues are likely to be concentrated in the
fiscal quarters prior to and during a particular growing season, which may
result in substantial variations in quarter-to-quarter financial results.
Unusual weather conditions, such as droughts or floods and the level of insect
pressure in grower areas also affect product sales from year-to-year.  In
addition, commercial introduction of the Company's new products is contingent
on, among other factors, completion of field testing and receipt of required
regulatory approvals.  Unusual weather conditions during field tests or failure
to receive regulatory approvals prior to the growing season may require
additional field tests in subsequent growing seasons, with resulting delays in
product development and commercialization.

Liquidity and Capital Resources
-------------------------------

During the first half of fiscal 2001, cash and cash equivalents declined $.2
million. Net cash used for operations was $.8 million of which $.4 million was
provided by net borrowings, $.2 million from proceed on the sale of assets and
$.2 million from the decrease in cash balances since October 31,2000. During the
first half of fiscal 2001, the Company borrowed $1.0 million pursuant to
promissory notes and made principal payments on debt of approximately $.6
million.

At April 30, 2001, the Company had limited liquid resources. At April 30,2001,
current liabilities were $7.7 million and current assets were $2.2 million
resulting in a working capital deficit of $5.5 million. Current liabilities
increased $.7 million from October 31,2000 due primarily to new borrowings and
the Company's inability to make timely payments. At April 30, 2001, the Company
had $3.1 million in accounts payable. Certain of these creditors have initiated
legal and other action for collection of amounts overdue aggregating $.2
million. Included in current liabilities at January 31, 2001 are net borrowings
under debt facilities of $2.7 million.

During fiscal 2000, the Company obtained a $1.5 million variable rate secured
term loan with the Berkshire Bank, a financial institution controlled by a
principal stockholder of United Equities (Commodities) Corporation, one of the
Company's principal stockholders. The maturity date of the Term Loan has been
extended to June 23, 2002 for all principal, interest and penalty payments.
However, in the event that the Company receives net proceeds in excess of $50
thousand from non-operating activity prior to June 23, 2002, the holder of the
term loan may elect to require a prepayment of the balance due on the loan.
Further, during fiscal 2001, a corporation controlled by the principal
stockholder loaned the Company $1.0 million pursuant to promissory notes ("the
Notes") which were due on June 30, 2001 and bears interest at 12%. The due date
for the notes has been extended until June 23, 2002. However, in the event that
the Company receives net proceeds in excess of $50 thousand from non-operating
activity prior to June 23, 2002, the holders of the promissory notes may elect
to require a prepayment of the balance due on the notes.

On September 11, 2000, the Company's common stock was delisted from the Nasdaq
National Market ("NNM") as a result of the Company's failure to meet the NNM's
net tangible assets listing requirement.  As a result, dividends on the
Company's Series 2000-A and Series 1998-C Convertible Preferred Stock are
payable in cash, effective with the quarterly dividend payment date of September
30, 2000 and the semiannual dividend payment date of December 31, 2000,
respectively.  The Company no longer has the option to pay such dividends in
stock. Under Delaware Law, the Company is precluded from paying cash dividends
due to its deficit in stockholders' equity and therefore is in default of its
preferred stock

                                       12
<PAGE>

To date, the Company has not generated positive cash flow from operations. Since
its inception, the Company financed its working capital needs primarily through
private and public offerings of equity and debt securities, revenues from
research and development alliances and product sales. The Company has secured
borrowings under a working capital line of credit, which expires on June 29,
2001, and a term loan and notes that are due on June 23, 2002. However, in the
event that the Company receives net proceeds in excess of $50 thousand from non-
operating activity prior to June 23, 2002, the holders of the term loan and the
promissory notes may elect to require a prepayment of the balance due on the
loan and/or the notes. The Company currently is not in compliance with the
covenants of its working capital line of credit. This line of credit had a
balance of $.2 million as of April 30, 2001 that has been reduced to $29
thousand at June 14, 2001. As a result of the Company's non-compliance with the
covenants, the working capital lender discontinued making loans and may, at its
option, liquidate the collateral including inventory and accounts receivable.

The Company continues to pursue the raising of additional funds and other
strategic initiatives including the sale of all or certain assets to improve its
working capital position. The Company has recently taken a number of steps to
conserve cash, including additional personnel reductions until it is able to
sell assets.  The Company needs to sell assets to provide the necessary cash
resources to repay the outstanding balances under its line of credit, the Term
Loan, the Notes, its accounts payable and fund operations. Further the Company
needs to continue to obtain short-term funding while it negotiates its strategic
transactions. At this time the Company is unable to predict whether it will be
successful in its efforts.  If the Company is not successful in obtaining
additional funding or selling assets, the Company will not be able to continue
as a going concern. Over the long-term, the Company's liquidity is dependent on
market acceptance of its products and technology. The report of our independent
auditors on the Company's consolidated financial statements for the year ended
October 31, 2000 included an explanatory paragraph which stated that the
recurring losses from operations, working capital deficiency, net capital
deficiency and limited liquid resources raise substantial doubt about the
Company's ability to continue as a going concern. The consolidated financial
statements do not include any adjustments that might result from the outcome of
this uncertainty.

Recently Issued Accounting Standards
------------------------------------

In December 1999, the staff of the Securities and Exchange Commission issued
Staff Accounting Bulletin No. 101, Revenue Recognition in Financial Statements
(SAB 101).  SAB 101 summarizes certain of the staff's views in applying
generally accepted accounting principles to revenue recognition in financial
statements.  SAB 101 required the Company to follow its guidance no later than
its fiscal year beginning November 1, 2000 through a cumulative effect of a
change in accounting principle.  Adoption of this standard did not have a
material impact on the Company's financial statements.

In June 1998, the Financial Accounting Standard Board issued Statement No. 133
"Accounting for Derivative Instruments and Hedging Activities" (FAS 133"). FAS
133 which was required to be adopted for the fiscal year beginning November 1,
2000. However, the Company has reviewed FAS 133 and because it does not use
derivatives, the adoption of FAS 133 did not effect the results of operations or
the financial position of the Company.

In April 2000, the Financial Accounting Standard Board Interpretation No. 44,
"Accounting for Certain Transactions Involving Stock Compensation-An
Interpretation of APB Opinion No. 25" ("FIN 44") was issued. Fin 44 clarifies
the application of APB No. 25 for certain issues. Among other issues, FIN 44
clarifies the definition of employee for purposes of applying APB no. 25, the
criteria for determining whether a plan qualifies as non-compensatory plan, the
accounting consequences of various modifications to the term of a previously
fixed stock option or award, and the accounting for an exchange of stock
compensation awards in a business combination. Fin 44 became effective July 1,
2000, but certain conclusions in this interpretation cover specific events that
occur after either December 15, 1998 or January 12, 2000. The adoption of FIN 44
did not have a significant effect on the Company's financial position or results
of operations.

                                       13
<PAGE>

Forward-Looking Statements
--------------------------

All statements contained in this management's discussion and analysis of
financial condition and results of operations other than statements of
historical information, are forward-looking statements. Forward-looking
statements include statements containing plans, objectives, goals, strategies,
future events or performance and underlying assumptions and other statements
which are other than historical facts. Although the Company believes that its
expectations are based on reasonable assumptions, the Company operates in a high
technology, emerging market environment that involves significant risks and
uncertainties which may cause actual results to vary from such forward-looking
statements and to vary significantly from reporting period to reporting period.
These risks include among others, those listed in "Factors That May Affect
Future Results", in the Company's Annual Report on Form 10K for the year ended
October 31, 2000, and other risks detailed from time to time in the Company's
filings with the Securities and Exchange Commission. The Company does not
undertake to update the results discussed herein as a result of changes in risks
or operating results.


PART II - OTHER INFORMATION

Item 6    Exhibits and reports in Form 8-K

(a) Exhibits

Exhibit No.    Description
-----------    -----------

3.1            Restated Certificate of Incorporation of Ecogen Inc. (Form 10-Q
               for fiscal quarter ended January 31, 1996)*

3.2            By-laws of Ecogen Inc., as amended (Form S-1 Registration
               Statement, File No. 33-14119)*

3.3            Certificate of Designations, Preferences and Rights of Series
               1998-A Convertible Preferred Stock (Form 10-Q for fiscal quarter
               ended April 30, 1998)*

3.4            Certificate of Designations, Preferences and Rights of Series
               1998-C Convertible Preferred Stock (Form 8-K, dated September 2,
               1998)*

3.5            Certificate of Designations, Preferences and Rights of Series
               1999-A Convertible Preferred Stock (Form 10-Q, for fiscal quarter
               ended April 30, 1999)*

3.6            Certificate of Designations, Preferences and Rights of Series
               2000-A Convertible Preferred Stock (Form 10-K, for fiscal year
               ended October 31, 1999)*

10.153         Asset Purchase and License Agreement between Ecogen Inc. and
               Mycogen Corporation dated as of February 15, 2000 (Current Report
               on Form 8-K dated March 1, 2000)*

10.154         Stockholders Agreement between Ecogen Inc. and Mycogen
               Corporation dated February 15, 2000 (Current Report on Form 8-K
               dated March 1, 2000)*

* These items are hereby incorporated by reference from the exhibits of the
  filing or report indicated and are made part of this Report.

                                       14
<PAGE>

10.155         Purchase and Sale Agreement between Ecogen Inc. and Dow
               AgroSciences LLC dated as of February 15, 2000 (Current Report on
               Form 8-K dated March 1, 2000)*

10.156         Convertible Preferred Stock Purchase Agreement between Ecogen
               Inc. and Amro International, S.A., Aspen International, Ltd. and
               Markham Holdings Limited dated as of February 14, 2000 (Form 10-Q
               for the fiscal quarter ended January 31, 2000) *

10.157         Registration Rights Agreement between Ecogen Inc. and Amro
               International, S.A., Aspen International, Ltd. and Markham
               Holdings Limited dated as of February 14, 2000 (Form 10-Q for the
               fiscal quarter ended January 31, 2000)*

10.158         International, S.A. dated February 14, 2000 (Form 10-Q for the
               fiscal quarter ended January 31, 2000)*

10.159         Warrant Agreement between Ecogen Inc. and Aspen International,
               Ltd. dated February 14, 2000 (Form 10-Q for the fiscal quarter
               ended January 31, 2000)*

10.160         Warrant Agreement between Ecogen Inc. and Markham Holdings
               Limited dated as of February 14, 2000 (Form 10-Q for the fiscal
               quarter ended January 31, 2000)*

10.161         Form of Demand Promissory Note to Momar Corporation (Form 10-K
               for the fiscal year ended October 31, 2000) *


(b)  Current Reports on Form 8-K

          None


* These items are hereby incorporated by reference from the exhibits of the
  filing or report indicated and are made part of this Report.

                                       15
<PAGE>

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.


Date:  June 19, 2001


                                  ECOGEN INC.



                                  By: /s/ James P. Reilly, Jr
                                      ------------------------------------------
                                      James P. Reilly, Jr.
                                      Chairman, Chief Executive
                                      Officer and Acting Chief Financial Officer

                                      16