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                                                                    EXHIBIT 99.1

               Immulogic Announces Sales of Its Drugs of Addiction
                   Vaccines Programs to Cantab Pharmaceuticals


WALTHAM, Mass., Dec. 21/PRNewswire/ C ImmuLogic Pharmaceutical Corporation
(Nasdaq: IMUL - news) announced today that it has entered into an agreement for
the sale of its drugs of addiction vaccines programs for the treatment of
nicotine and cocaine addiction to Cantab Pharmaceuticals plc (Nasdaq: CNTBY;
LSE: CTB). Under the terms of the agreement, Cantab will pay a maximum initial
consideration of U.S. $9 million which is to be satisfied by the issue of up to
2,566,845 new Cantab Ordinary Shares of 2p each in the form of American
Depositary Shares (ADSs), in return for the transfer from ImmuLogic of the two
vaccine programs and U.S. $6 million in cash to help fund the development of
these vaccines.

In addition, Cantab will pay ImmuLogic a maximum further U.S. $11.0 million in
milestone payments contingent upon successful development of the two programs to
the end of Phase II clinical trials. These payments may be made in cash or in
additional ADSs or a combination thereof at Cantab's option. Cantab will also
pay ImmuLogic a share of the net royalties it receives proportionate to the
level of worldwide product sales achieved. Closing of the acquisition, which is
subject to the satisfaction of a number of pre-conditions, is expected to take
place in late January, 1999.

ImmuLogic has agreed it will not sell any of the American Depository Shares or
Cantab Ordinary Shares within six months following their issue. Thereafter,
ImmuLogic may sell up to 25% of such shares in each of the four quarters
following the expiration of the initial six-month period.

The two vaccine programs target addictions to cocaine and nicotine. The cocaine
vaccine is in a Phase I clinical trials in the U.S.; the nicotine vaccine is in
the final stages of preclinical development.

"We are very excited by this acquisition of these products which is in line with
our strategy to build our pipeline at all stages of product development," said
Jurek Sikorski, Chief Executive of Cantab. "These are novel products that
represent a strong fit within our current pipeline of immunotherapeutic vaccines
and capitalize on our scientific and medical expertise in immunology and vaccine
development. Commercially, they are exciting as together they address a
potentially huge market with very little currently available in the way of
effective treatments."

The scientific rationale behind this novel approach is very clear, "said John
Shields, Ph.D., Cantab's Senior Vice President, New Projects. "The preclinical
data supporting these products is impressive, and we are delighted to be able to
add these programs to our portfolio."


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"I view this as a very positive step for both ImmuLogic and Cantab. Our novel
drugs of addiction vaccines will become part of a broad vaccine portfolio under
development at Cantab. Our products complement that portfolio and expand the
purview. ImmuLogic is pleased to have been able to enlist the scientific and
clinical talent at Cantab in the further development of these vaccines which
address such significant medical and social problems," said J. Joseph Marr,
M.D., President and Chief Executive Officer of ImmuLogic.

Dr. Marr added, "This year, ImmuLogic has been quite successful in concluding
corporate arrangements with Sankyo, Heska Corporation [Nasdaq:HSKA - news], and
now Cantab Pharmaceuticals. This arrangement to transfer our drugs of addiction
programs to Cantab leaves ImmuLogic in a very strong cash position. Over the
next few months, management and the Board of Directors will explore in detail a
number of strategic options."

ImmuLogic Pharmaceutical Corporation is a biopharmaceutical company located in
Waltham, Massachusetts. The Company's press releases are available through
Company News on Call by fax at 800-758-5804, ext. 114501, and on the Internet at
www.prnewswire.com.

Cantab Pharmaceuticals plc, based in Cambridge, England, was established in 1989
to exploit advances in immunology. Cantab has become a leader in the field of
immunotherapy, developing novel products for the treatment and prevention of
infectious diseases and cancer through the use of its proprietary antigen and
gene delivery system.

This press release contains forward-looking statements that involve a number of
risks and uncertainties, including risks and uncertainties that relate to
restructuring of its operations and licensing of its product candidates. Among
the most important factors that could cause actual results to differ materially
from those indicated by such forward-looking statements are delays in product
development, failure to obtain required regulatory approvals, and the other risk
factors detailed in the Company's Annual Report on Form 10-K for the year ended
December 31, 1997.