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CONTACT:
Elkan R. Gamzu, Ph.D.                               Michelle Linn
President and CEO                                   Vice President
Cambridge NeuroScience, Inc.                        Feinstein Kean Partners Inc.
(617) 225-0600 ext. 116                             (617) 577-8110


FOR IMMEDIATE RELEASE
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        CAMBRIDGE NEUROSCIENCE DISCONTINUES TRAUMATIC BRAIN INJURY TRIAL

   --PRELIMINARY ANALYSIS DEMONSTRATES HIGH DEGREE OF SAFETY BUT INSUFFICIENT
                                  EFFICACY --


CAMBRIDGE, MASSACHUSETTS, SEPTEMBER 16, 1997 -- Cambridge NeuroScience, Inc.
(Nasdaq: CNSI) today announced the discontinuation of its Phase III trial of
CERESTAT(1) for traumatic brain injury (TBI) because a planned interim analysis
of the data showed insufficient evidence of positive clinical impact. Analysis
of the data also showed that on a wide variety of safety parameters, the drug
was safe and well tolerated. The company, in collaboration with its partner
Boehringer Ingelheim, will continue to collect further data and conduct an
in-depth analysis on the more than 500 patients enrolled to date, to further
document the substantial safety for possible future clinical development of the
drug.

"While we are clearly disappointed by this outcome, it is important to note that
this trial was both well designed and well conducted. As a consequence, the high
quality of the data allowed us to make this decision expeditiously, enabling our
clinical investigators to focus on other clinical trials," said Elkan R. Gamzu,
Ph.D., President and Chief Executive Officer of Cambridge NeuroScience, Inc.
"Our priorities for CERESTAT now are to complete the analysis of the Phase III
stroke data so that a decision can be made on resumption of the trial, and to
explore the viability of other clinical applications," Dr. Gamzu added.

The interim analysis included data from 340 patients treated within eight hours
of a traumatic brain injury. Patients were randomized to placebo or a regimen of
CERESTAT that involved a bolus of 15 mg followed by a 72 hour infusion of 3 mg
per hour. This dose was 16 times higher than the highest dose used in the
CERESTAT Phase III stroke trial. The measure used for the interim analysis was
assessment at three months on the Glasgow Outcome Score, a standard used
worldwide to measure clinical outcome following brain injury. The lack of
differentiation between the two treatment groups suggested that continuation
would be unlikely to lead to a statistically significant outcome. In terms of
safety, the two groups were essentially indistinguishable.



                                    --More--


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Cambridge NeuroScience, Inc. is a leading neuroscience company engaged in the
discovery and development of proprietary pharmaceuticals focusing on nerve cell
survival. The Company is developing a number of products to treat stroke,
traumatic brain injury and chronic neurodegenerative disorders such as multiple
sclerosis, peripheral neuropathies and other degenerative diseases.

Boehringer Ingelheim, with headquarters in Ingelheim, Germany, is an
international R&D-oriented pharmaceutical company with total worldwide sales of
more than 7 billion Deutschemarks ($4.4 billion U.S.). Boehringer Ingelheim
spent 1.1 billion Deutschemarks ($750 million U.S.) last year on R&D, focusing
on innovative products for the treatment of acute chronic conditions associated
with respiratory, cardiovascular, CNS and gastrointestinal disorders. The
headquarters for the U.S. operations, Boehringer Corporation, is located in
Ridgefield, Connecticut.

This press release contains forward-looking statements based on the current
expectations of management. There are certain important factors that could cause
results to differ from those anticipated by the statements made above,
including, but not limited to, the continued funding of the Company's
development program from Boehringer Ingelheim under the Boehringer Ingelheim
collaborative agreement, the results of in-depth analysis of the Phase III
traumatic brain injury and stroke trials, and the acceptance by regulatory
authorities of the Company's clinical trial outcomes as a basis for marketing
approval.

(1)  CERESTAT is a registered trademark of Boehringer Ingelheim International 
     GmbH.
     


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