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                                                                    EXHIBIT 99.3

        UNAUDITED PRO FORMA CONDENSED CONSOLIDATED FINANCIAL INFORMATION


     The following unaudited pro forma condensed consolidated financial
statements reflect the merger of Antigenics Inc. and Aquila Biopharmaceuticals,
Inc. in a transaction accounted for as a purchase business combination.

     The unaudited pro forma condensed consolidated balance sheet as of
September 30, 2000 has been prepared as if the merger had occurred on September
30, 2000. The unaudited pro forma condensed consolidated balance sheet combines
the historical balance sheets of Antigenics and Aquila at September 30, 2000,
and gives effect to the unaudited pro forma adjustments necessary to account for
the merger as a purchase.

     The unaudited pro forma condensed consolidated statements of operations
have been prepared as if the merger had occurred on January 1, 1999. These
unaudited pro forma condensed consolidated statements of operations combine the
historical statements of operations of Antigenics for the year ended December
31, 1999 and the nine months ended September 30, 2000 with the historical
statements of operations of Aquila for the year ended December 31, 1999 and the
nine months ended September 30, 2000, respectively, and give effect to the
unaudited pro forma adjustments necessary to account for the merger as a
purchase.

     The unaudited pro forma adjustments reflect the purchase price allocations
made by Antigenics based on an appraisal of the intangible assets of Aquila and
other available information that Antigenics believes to be reasonable. The
unaudited pro forma condensed consolidated financial statements are provided for
illustrative purposes only and do not purport to represent what Antigenics'
results of operations or financial position would actually have been, had the
merger in fact occurred on such dates, nor do they purport to project the
results of operations or financial position of Antigenics for any future period
or date.

     The unaudited pro forma condensed consolidated financial statements should
be read in conjunction with the audited and unaudited financial statements and
accompanying notes of Antigenics, which have been previously filed, and of
Aquila, which are included elsewhere in this filing.

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            UNAUDITED PRO FORMA CONDENSED CONSOLIDATED BALANCE SHEET
                                 (IN THOUSANDS)



                                                                              Nine Months Ended September 30, 2000
                                                            ----------------------------------------------------------------------

                                                            Historical          Historical         Adjustments
                                                            Antigenics            Aquila            for Merger           Pro Forma
                                                            ----------          ----------         -----------           ---------

                                                                                                             
   ASSETS
   Current assets:
          Cash, cash equivalents and marketable
            securities................................      $ 101,553           $   6,458                                $ 108,011
          Receivables, net............................             --                 930                                      930
          Inventories.................................             --                 666                                      666
          Deferred acquisition costs..................            690                  --                (690)A                 --
          Other current assets........................            500                 175                                      675
                                                            ---------           ---------                                ---------

          Total current assets........................        102,743               8,229                                  110,282

   Plant and equipment, net...........................          8,624               5,656                                   14,280
   Intangible assets..................................             --                  19                 (19)A              6,710
                                                                                                        6,710 A                 --
   Goodwill...........................................             --                  --               2,718 A              2,718
   Other assets.......................................            731               1,088                (150)C              1,669
                                                            ---------           ---------                                ---------

          Total assets................................      $ 112,098           $  14,992                                $ 135,659
                                                            =========           =========                                =========

   LIABILITIES AND STOCKHOLDERS' EQUITY
   Accounts payable...................................      $   1,710           $     366                                $   2,076
   Accrued liabilities................................          1,338               1,496               1,930 A              4,764
   Current portion, long-term debt....................            906               1,360                                    2,266
                                                            ---------           ---------                                ---------

          Total current liabilities...................          3,954               3,222                                    9,106

   Long-term debt.....................................          1,463               1,728                                    3,191
   Other Liabilities..................................             --                 150               (150)C                  --


   Stockholders' Equity:

          Common stock................................            248                  86                  25 B                273
                                                                                                          (86)B
          Treasury Stock..............................             --                 (34)                 34 B                 --
          Additional paid-in capital..................        159,326             145,743              42,456 B            201,782
                                                                                                     (145,743)B
          Deferred compensation.......................         (1,316)                 --                                   (1,316)
          Accumulated deficit.........................        (51,577)           (135,903)            (25,800)A            (77,377)
                                                                                                      135,903 B
                                                            ---------           ---------                                ---------

          Total stockholders' equity..................        106,681               9,892                                  123,362
                                                            ---------           ---------                                ---------

          Total liabilities and stockholders' equity..        112,098              14,992                                  135,659
                                                            =========           =========                                =========

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       UNAUDITED PRO FORMA CONDENSED CONSOLIDATED STATEMENT OF OPERATIONS
                      (in thousands, except per share data)



                                                                         Year Ended December 31, 1999
                                                       ------------------------------------------------------------

                                                       Historical         Historical      Adjustments
                                                       Antigenics           Aquila         for Merger     Pro Forma
                                                       ----------         ----------      -----------     ---------
                                                                                              
Revenue.............................................   $        -         $    2,068                      $   2,068
Costs and expenses:
              Cost of sales.........................            -                858                            858
              Research and development..............       11,845              6,643      $       993 D      19,481
              General and administrative............        7,012              3,026                         10,038
                                                       ----------         ----------                      ---------
                           Operating loss...........      (18,857)            (8,459)                       (28,309)
Other income (expense);
              Interest income.......................        1,014                544                          1,558
              Other, net............................         (281)              (280)                          (561)
                                                       ----------         ----------                      ---------

Loss before nonrecurring charges directly
     attributable to the acquisition................   $  (18,124)        $   (8,195)                 E   $ (27,312)
                                                       ==========         ==========                      =========

Weighted average number of common shares
     outstanding, basic and diluted.................       18,144                               2,498 F      20,642
                                                       ==========                                         =========

Loss before nonrecurring charges directly
     attributable to the acquisition per common
     share, basic and diluted.......................   $    (1.00)                                        $   (1.32)
                                                       ==========                                         =========





       UNAUDITED PRO FORMA CONDENSED CONSOLIDATED STATEMENT OF OPERATIONS
                      (in thousands, except per share data)



                                                                     Nine Months Ended September 30, 2000
                                                       ------------------------------------------------------------

                                                       Historical         Historical      Adjustments
                                                       Antigenics           Aquila         for Merger     Pro Forma
                                                       ----------         ----------      -----------     ---------
                                                                                              
Revenue............................................    $        -         $    3,523                      $   3,523
Costs and expenses:
              Cost of sales........................             -              1,040                          1,040
              Research and development.............        12,694              4,526      $       768 D      17,988
              General and administrative...........         5,491              2,045             (145)G       7,391
                                                       ----------         ----------                      ---------
                           Operating loss..........       (18,185)            (4,088)                       (22,896)
Other income (expense);
              Interest income......................         4,521                285                          4,806
              Other, net...........................          (296)               368                             72
                                                       ----------         ----------                      ---------

Loss before nonrecurring charges directly
     attributable to the acquisition...............    $  (13,960)        $   (3,435)                 E   $ (18,018)
                                                       ==========         ==========                      =========

Weighted average number of common shares
     outstanding, basic and diluted................        24,193                               2,498 F      26,691
                                                       ==========                                         =========

Loss before nonrecurring charges directly
     attributable to the acquisition per common
     share, basic and diluted......................    $    (0.58)                                        $   (0.68)
                                                       ==========                                         =========

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   NOTES TO UNAUDITED PRO FORMA CONDENSED CONSOLIDATED FINANCIAL INFORMATION

Note A.

     Reflects the allocation of the purchase price to the net assets of Aquila.
     Under purchase accounting, the assets and liabilities of Aquila are
     required to be adjusted to their fair values. The purchase price of
     $44,496,000 is the sum of (i) $39,936,000 representing approximately
     2,498,000 shares of Antigenics stock valued at approximately $15.98 per
     share, which represents the average closing price per share of Antigenics
     stock for the five days before and after the announcement of the merger on
     August 18, 2000, issued at an exchange ratio of 0.2898 shares of Antigenics
     common stock for each of the 8,619,000 outstanding shares of Aquila stock
     as of November 16, 2000 (the consummation date of the merger), (ii)
     $2,545,000 representing the fair value of Aquila options and warrants to
     acquire Aquila stock which was vested upon the consummation of the merger
     and exchanged for options to purchase 264,000 shares of Antigenics common
     stock and warrants to purchase 18,000 shares of Antigenics common stock and
     (iii) an estimated $2,015,000 of Antigenics' costs of the merger and the
     cost to sever the employment of Aquila's president. The fair value of the
     Aquila options and warrants has been calculated using an option pricing
     model with the following weighted average assumptions: life of the option -
     6 years; dividend yield - nil; risk-free interest rate - 5.50%; price
     volatility - 74.0%.

     The following are the pro forma adjustments made to reflect the allocation
     of the purchase price to the estimated fair value of the net assets
     acquired based upon valuations of Aquila's intangible assets and other
     available information. The valuation of acquired in-process research and
     development below represents the estimated fair value of products under
     development at Aquila calculated using an income approach. This involves
     estimating the fair value of the in-process research and development using
     the present value of the estimated after-tax cash flows expected to be
     generated by the acquired in-process research and development projects. A
     risk-adjusted discount rate of 60% has been utilized for each specific
     product. Cash inflows from projects begin primarily in 2003 and 2004, the
     expected dates of product approvals. Gross margins on products are
     estimated at levels consistent with industry expectations.


                                                                              
       Purchase price.........................................................   $ 44,496,000
       Net assets of Aquila (1)...............................................     (9,873,000)
                                                                                 ------------
                 Subtotal.....................................................     34,623,000
                                                                                 ------------

       Fair value adjustments:
             Core and developed technology....................................      6,200,000
             Assembled work force.............................................        510,000
             Acquired in-process research and development (2).................     25,800,000
             Liabilities assumed (3)..........................................       (605,000)
                                                                                 ------------
                  Subtotal....................................................     31,905,000
                                                                                 ------------
       Excess of cost over fair value of net assets acquired (goodwill).......   $  2,718,000
                                                                                 ============


     (1)  Represents the historical Aquila net assets adjusted to eliminate
          historical patents and purchased technology, net of $19,000.

     (2)  Antigenics will record an immediate write-off of acquired in-process
          research and development costs at the consummation of the merger. The
          write-off is not



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          reflected in the unaudited pro forma condensed consolidated statements
          of operations because it is nonrecurring in nature. This nonrecurring
          charge is reflected in the unaudited pro forma condensed consolidated
          balance sheet as of September 30, 2000 as an increase to accumulated
          deficit.

     (3)  Reflects the additional transaction-related expenses incurred by
          Aquila between September 30, 2000 and the date of the merger. Such
          expenses have not been reflected in the unaudited pro forma condensed
          consolidated statements of operations because they are nonrecurring in
          nature.

Note B.

     Reflects the elimination of the historical Aquila equity balances and the
     issuance of Antigenics' common stock, options and warrants as consideration
     for the merger.

Note C.

     Reflects the elimination of deferred revenue and related other assets.

Note D.

     Reflects the amount by which the pro forma amortization of core and
     developed technology resulting from the merger on a straight-line basis
     over 10 years and the amortization of the assembled workforce on a
     straight-line basis over 3 years ($790,000 per year or $593,000 for nine
     months) exceeds the amortization of Aquila's historical intangible
     amortization ($69,000 and $29,000 for the year ended December 31, 1999 and
     the nine months ended September 30, 2000, respectively) and the
     amortization of goodwill resulting from the merger on a straight-line basis
     over 10 years ($272,000 per year and $204,000 for the nine months).

Note E.

     No pro forma income tax provision (benefit) is recognized because of a loss
     before income taxes in each period and the need to recognize a valuation
     allowance on deferred tax assets. Given the history of incurring losses,
     Antigenics believes that it is more likely than not that any deferred tax
     assets will not be realized.

Note F.

     The weighted average number of outstanding common shares outstanding
     assumes that the shares issued in the merger (2,498,000 shares of
     Antigenics common stock) are outstanding throughout each period. Options
     and warrants to purchase Aquila common stock will become options and
     warrants to purchase Antigenics stock. The pro forma loss before
     nonrecurring charges directly attributable to the acquisition and the
     weighted average number of common shares outstanding used for computing
     diluted loss before nonrecurring charges directly attributable to the
     acquisition per common share are the same as that used for computing basic
     loss before nonrecurring charges directly attributable to the acquisition
     per common share for each period because inclusion of the options and
     warrants in the calculation would be antidilutive (i.e., would reduce the
     loss per common share).


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Note G.

     Reflects the nonrecurring transaction-related expenses incurred by Aquila
     prior to September 30, 2000.