IMMUNOMEDICS RAISES $37.2 MILLION IN PRIVATE STOCK OFFERING

Morris Plains, NJ, February 17, 2000 --- Immunomedics,  Inc. (NASDAQ:IMMU) today
announced  that it has completed a private  placement of 2.325 million shares of
Common Stock to a group of investors for gross  revenues of $ 37.2 million.  The
Company  intends  to file a  registration  statement  in  connection  with these
shares. The offering was managed by Sutro & Co.

Incorporated.  Immunomedics'  Chairman and Chief Executive Officer, Dr. David M.
Goldenberg, remarked: "We are pleased to add this working capital to our balance
sheet so that we can accelerate the clinical  development of  CEA-Cide(TM),  our
therapeutic product for several major cancers. We are currently  evaluating this
agent in Phase I/II clinical  trials in colorectal,  pancreatic,  lung,  breast,
ovarian,  and medullary  thyroid  cancers." "We remain on course to consummate a
licensing   partnership  for   LymphoCide(TM),   our  therapeutic   product  for
non-Hodgkin's    lymphoma,"   he   commented   further.    Immunomedics   is   a
biopharmaceutical   company   focused  on  the   development,   manufacture  and
commercialization  of  diagnostic  imaging  and  therapeutic  products  for  the
detection and  treatment of cancer and  infectious  diseases.  Integral to these
products  are highly  specific  monoclonal  antibodies  and  antibody  fragments
designed  to deliver  radioisotopes  and  chemotherapeutic  agents to tumors and
sites of infection.  The Company's first product,  CEA-Scan(R) for the detection
of  colorectal  cancer,  is being  marketed  in the  United  States  and  Europe
(approved  in  Canada).   The  Company's  second  diagnostic   imaging  product,
LeukoScan(R),  is being  marketed in Europe for the  diagnosis of  osteomyelitis
(bone  infection).  Immunomedics  also  has  several  other  diagnostic  imaging
products and three  therapeutic  products in clinical trials.  This release,  in
addition to historical  information,  contains  forward-looking  statements made
pursuant  to  the  Private  Securities  Litigation  Reform  Act  of  1995.  Such
statements involve  significant risks and uncertainties and actual results could
differ  materially from those  expressed or implied  herein.  Factors that could
cause such  differences  include,  but are not limited to, risks associated with
new product  development  (including  clinical  trials  outcome  and  regulatory
requirements/actions),  competitive  risks to marketed products and availability
of financing and other sources of capital, as well as the risks discussed in the
Company's Quarterly Report on Form 10-Q for the quarter ended December 31, 1999.
Company Contact: Cynthia L. Sullivan,  Executive Vice President, (973) 605-8200,
extension 109. Visit our web site at http://www.Immunomedics.com.