Holding in Company

Cambridge, UK and Cambridge, Massachusetts - 3 December 2003 - Acambis plc
("Acambis") (LSE: ACM, NASDAQ: ACAM) announces that it has today received
notification that as from 28 November 2003 Barclays PLC no longer held a
notifiable interest in the share capital of Acambis.

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Enquiries:

Acambis plc                                                                    
                                                                               
Elizabeth Brown, VP Finance and Company    Tel: +44 (0) 1223 275 300           
Secretary                                                                      
                                                                               
Lyndsay Wright, Director of Communications                                     

Notes to editors:

Acambis is a leading developer of vaccines to prevent and treat infectious
diseases. Recognised internationally as the leading producer of smallpox
vaccines, Acambis is developing a second-generation smallpox vaccine which is
currently undergoing clinical trials and, under a unique arrangement given the
threat of smallpox being used as a bioterrorist weapon, is manufacturing
emergency-use stockpiles of this investigational vaccine for the US Government
and other governments around the world. Acambis is establishing a travel
vaccines franchise through its US-based subsidiary Berna Products Corporation,
which markets Vivotif�, the world's only oral typhoid vaccine, in North
America. Acambis has a number of other potential travel vaccines in development
and is conducting clinical trials of vaccines against yellow fever, Japanese
encephalitis and dengue fever. Acambis recently became the first company to
start human clinical trials of a vaccine targeting the West Nile virus, which
has spread to 45 US States in the last four years.

Acambis is based in Cambridge, UK and Cambridge, Massachusetts, US. Its primary
listing is on the London Stock Exchange (ACM) and its shares are listed in the
form of American Depositary Receipts on Nasdaq (ACAM). More information is
available at www.acambis.com.

"Safe Harbor" statement under the Private Securities Litigation Reform Act of
1995:

The statements in this news release that are not historical facts are
forward-looking statements that involve risks and uncertainties, including the
timing and results of clinical trials, product development, manufacturing and
commercialisation risks, the risks of satisfying the regulatory approval
process in a timely manner, the need for and the availability of additional
capital. For a discussion of these and other risks and uncertainties see "Risk
factors" in the Company's Annual Report and Form 20-F for the most recently
ended fiscal year, in addition to those detailed in the Company's filings made
with the Securities and Exchange Commission from time to time. These
forward-looking statements are based on estimates and assumptions made by the
management of Acambis and are believed to be reasonable, though are inherently
uncertain and difficult to predict. Actual results or experience could differ
materially from the forward-looking statements.



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