UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549


                                    FORM 8-K
                                 CURRENT REPORT

                     Pursuant to Section 13 or 15(d) of the
                         Securities Exchange Act of 1934



                Date of Report (Date of earliest event reported):
                                 April 21, 2004


                         AVANT IMMUNOTHERAPEUTICS, INC.
               (Exact name of registrant as specified in charter)


         Delaware                        0-15006                13-3191702
(State or other jurisdiction     (Commission file number)      (IRS employer
     of incorporation)                                       identification no.)


                                119 Fourth Avenue
                          Needham, Massachusetts 02494
               (Address of principal executive offices) (Zip code)


               Registrant's telephone number, including area code:
                                 (781) 433-0771


ITEM 7. FINANCIAL STATEMENTS, PRO FORMA FINANCIAL INFORMATION AND EXHIBITS. (c) Exhibits. 99.1 The Company's Press Release dated April 21, 2004. ITEM 9. REGULATION FD DISCLOSURE. The following information is furnished under Item 12 of Form 8-K "Results of Operations and Financial Condition". This information is being furnished and shall not be deemed "filed" for the purposes of Section 18 of the Securities Exchange Act of 1934 or otherwise subject to the liabilities of that Section. The information in this Current Report on Form 8-K shall not be incorporated by reference into any registration statement or other document pursuant to the Securities Act of 1933 as amended. On April 21, 2004, the Company issued a press release which is attached to this Form 8-K as Exhibit 99.1 and incorporated herein by reference.

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 hereunto duly authorized. AVANT IMMUNOTHERAPEUTICS, INC. Date: April 21, 2004 By: /s/ Avery W. Catlin ------------------------- Avery W. Catlin Senior Vice President and Chief Financial Officer

EXHIBIT INDEX Exhibit Sequential Number Description Page Number - ------- ----------- ----------- 99.1 The Company's Press Release 4 dated April 21, 2004

                                                                    Exhibit 99.1

  AVANT Immunotherapeutics Reports First Quarter Fiscal 2004 Financial Results

     NEEDHAM, Mass.--(BUSINESS WIRE)--April 21, 2004--AVANT Immunotherapeutics,
Inc. (Nasdaq: AVAN) today reported financial results for the first quarter ended
March 31, 2004. The Company reported a net loss of $1.9 million, or $0.03 per
share, for the first quarter of 2004 compared to a net loss of $3.4 million, or
$0.06 per share, for the first quarter of 2003. The decreased loss for the first
quarter of 2004 primarily reflects an increase in revenue, offset partly by an
increase in operating expense and a decrease in interest income compared to the
same period in 2003.
     The increase in revenue of $2,349,000 in 2004 results primarily from the
recognition of $1 million in revenue from DynPort Vaccine Company LLC ("DVC")
for rPA clinical materials, the recognition of an upfront license fee of $1
million from Adprotech, Ltd and an increase in government contract revenues from
DVC of $402,900. The increase in operating expense of $828,100, or 19.9%,
results primarily from an increase in research and development expense in the
first quarter of 2004 due to increased clinical trials costs and contract
manufacturing costs incurred on the TP10 program, offset in part by a decrease
in licensing fees. The increase in operating expense further resulted from an
increase of $67,400 in general and administrative personnel-related expense. The
decrease in investment income of $68,100 reflected lower interest rates in 2004.
At March 31, 2004, the Company reported cash and cash equivalents of $41.2
million.
     "Since January we achieved several notable clinical and financial
milestones that bring us a step closer to becoming a commercial company and
realizing the full value of our technologies and products," said Una S. Ryan,
Ph.D., President and Chief Executive Officer of AVANT Immunotherapeutics, Inc.

     --   With our partner GlaxoSmithKline (GSK), our Rotarix(R) vaccine is
          completing Phase III clinical studies in Latin America and Southeast
          Asia. GSK is investing 450 million euros in a new facility in Belgium
          to produce Rotarix(R) and another vaccine.

     --   We released positive preliminary results of the adult portion from the
          Phase II clinical trial in Bangladesh of AVANT's cholera vaccine,
          CholeraGarde(TM).

     --   During the quarter we completed a financing of approximately $25
          million that gives us a cash balance greater than our currently
          anticipated requirements for the next two years.

     --   We began a Phase IIb trial of TP10, our novel inhibitor of
          complement-mediated inflammation, in approximately 300 female patients
          undergoing cardiac surgery utilizing cardiopulmonary bypass.

     --   Finally, we have completed the design phase of our pilot manufacturing
          facility in Fall River and expect to start construction shortly. This
          facility will implement our VitriLife(R) technology.

     Commitment to a Cholesterol Management Vaccine

     We are evaluating a number of possibilities for the continued development
of our CETP vaccine for cholesterol management, including the use of new
adjuvants to elicit a more robust antibody response. We are strongly committed
to this program and expect to have CETi back into the clinic in approximately 12
months.

     Bioterrorism Vaccines

     AVANT has continued to make technical progress under its subcontracts with
DVC towards development of anthrax and plague vaccines for the Department of
Defense. This morning we also announced that AVANT has been awarded a new
subcontract by DVC for $3 million to support the human clinical testing of a
plague vaccine candidate. AVANT continues to seek dedicated funding to provide
financial support for the vaccines' preclinical and clinical development,
including manufacturing process development and pilot vaccine production at
AVANT's Fall River pilot manufacturing plant.
     During 2003, AVANT entered into an agreement with DVC for the replacement
of recombinant Protective Antigen ("rPA") clinical materials used by DVC in the
Phase I clinical trial of DVC's injectable anthrax vaccine candidate. Under the
agreement, AVANT recognized $1 million in revenue from DVC in the first quarter
of 2004.

     Webcast and Conference Call

     Dr. Ryan and Mr. Catlin will host a conference call at 11:00 AM EDT on
Wednesday, April 21, 2004 to discuss AVANT's First Quarter 2004 financial
results. To access the conference call, dial 800-901-5231 (within the United
States), or 617-786-2961 (if calling from outside the U.S.). The passcode for
participants is 28467259. An audio replay will be available approximately two
hours after the call for approximately one week and can be accessed by dialing
888-286-8010 (within the U.S.), or 617-801-6888 (if calling from outside the
U.S.). The passcode I.D.# is 22970356.
     A live webcast of the conference call, together with this press release,
can be accessed through the company's web site www.avantimmune.com in the
Investor Information section. In order to access the webcast, your PC must have
a sound card, speakers and Windows Media Player software. It is recommended that
you configure your PC in advance of the webcast as the software download and
installation can take several minutes. In addition, the call and webcast will be
archived and can be accessed through the same link. Additionally, a copy of this
press release is available by contacting Investor Relations at (781) 433-0771.
     AVANT Immunotherapeutics, Inc. discovers, develops and sells innovative
vaccines and therapeutics that harness the human immune system to prevent and
treat disease. The company has developed a broad, well-staged pipeline of
vaccines and therapeutics for large, high-value, under-served markets. Six of
AVANT's products are in clinical development. These include an oral human
rotavirus vaccine, a treatment to reduce complement-mediated tissue damage
associated with cardiac by-pass surgery, and a novel vaccine for cholesterol
management. AVANT has also assembled a technology platform that enables the
creation of rapid-protecting, single-dose, oral vaccines that remain stable
without refrigeration. The company is developing applications of this vaccine
technology in four areas: biodefense, travelers' vaccines, global health needs,
and human food safety. AVANT's goal is to demonstrate proof-of-concept for its
products before leveraging further development through both traditional
pharmaceutical partnerships and collaborations with governmental and other
organizations.
     Additional information on AVANT Immunotherapeutics, Inc. can be obtained
through our site on the World Wide Web: http://www.avantimmune.com.

     Safe Harbor Statement Under the Private Securities Litigation Reform Act of
1995: This release includes forward-looking statements which reflect AVANT's
current views with respect to future events and financial performance. These
forward-looking statements are based on management's beliefs and assumptions and
information currently available. The words "believe", "expect", "anticipate",
"intend", "estimate", "project" and similar expressions which do not relate
solely to historical matters identify forward-looking statements. Investors
should be cautious in relying on forward-looking statements because they are
subject to a variety of risks, uncertainties, and other factors that could cause
actual results to differ materially from those expressed in any such
forward-looking statements. These factors include, but are not limited to: (1)
the integration of multiple technologies and programs; (2) the ability to adapt
AVANT's vectoring systems to develop new, safe and effective orally administered
vaccines against anthrax and plague or other bioterrorism threats or emerging
health care threats; (3) the ability to successfully complete development and
commercialization of TP10, CETi-1, CholeraGarde(TM) (Peru-15), Ty800 and other
products; (4) the cost, timing, scope and results of ongoing safety and efficacy
trials of TP10, CETi-1, CholeraGarde(TM) (Peru-15), Ty800 and other preclinical
and clinical testing; (5) the ability to successfully complete product research
and further development, including animal, pre-clinical and clinical studies of
TP10, CETi-1, CholeraGarde(TM) (Peru-15), Ty800 and other products; (6) the
ability of the Company to manage multiple late stage clinical trials for a
variety of product candidates; (7) the volume and profitability of product sales
of Megan(R)Vac 1, Megan(R)Egg and other future products; (8) changes in existing
and potential relationships with corporate collaborators; (9) the availability,
cost, delivery and quality of clinical and commercial grade materials supplied
by contract manufacturers; (10) the timing, cost and uncertainty of obtaining
regulatory approvals to use TP10, CETi-1, CholeraGarde(TM) (Peru-15) and Ty800,
among other purposes, for adults undergoing cardiac surgery, to raise serum HDL
cholesterol levels and to protect travelers and people in endemic regions from
diarrhea causing diseases, respectively; (11) the ability to obtain substantial
additional funding; (12) the ability to develop and commercialize products
before competitors; (13) the ability to retain certain members of management;
and (14) other factors detailed from time to time in filings with the Securities
and Exchange Commission. We expressly disclaim any responsibility to update
forward-looking statements.


                    AVANT IMMUNOTHERAPEUTICS, INC.


CONSOLIDATED STATEMENT                                Quarter
OF OPERATIONS DATA                                 Ended March 31,
                                                 2004         2003
                                                    (Unaudited)
OPERATING REVENUE
Product Development
 and Licensing Agreements                    $2,124,400     $169,400
Government Contract Revenue                     879,900      477,000
Product Royalties                                26,400       35,300

Total Operating Revenue                       3,030,700      681,700

OPERATING EXPENSE
Research and Development                      3,453,200    2,692,500
General and Administrative                    1,292,100    1,224,700
Amortization of Acquired Intangible Assets      248,800      248,800

Total Operating Expense                       4,994,100    4,166,000

Operating Loss                               (1,963,400)  (3,484,300)

Investment Income, Net                           54,000      122,100

Net Loss                                    $(1,909,400) $(3,362,200)

Basic and Diluted Net Loss per
 Common Share                                    $(0.03)      $(0.06)
Weighted Average Common
 Shares Outstanding                          69,169,600   60,468,600



CONDENSED CONSOLIDATED
BALANCE SHEETS                               March 31,   December 31,
                                               2004         2003
                                            (Unaudited)
ASSETS
Cash and Cash Equivalents                   $41,161,500  $20,251,000
Other Current Assets                          2,282,300    2,058,000
Property and Equipment, net                   1,053,100      912,700
Intangible and Other Assets, net              7,834,500    8,083,400
  Total Assets                              $52,331,400  $31,305,100

LIABILITIES AND STOCKHOLDERS' EQUITY
Current Liabilities                          $2,941,200   $3,385,400
Stockholders' Equity                         49,390,200   27,919,700
  Total Liabilities and Stockholders'
   Equity                                   $52,331,400  $31,305,100


    CONTACT: AVANT Immunotherapeutics, Inc.
             Una S. Ryan, Ph.D., 781-433-0771
             or
             AVANT Immunotherapeutics, Inc.
             Avery W. Catlin, 781-433-0771
             info@avantimmune.com
             or
             For Media:
             Kureczka/Martin Associates
             Joan Kureczka, 415-821-2413
             jkureczka@aol.com