SCHEDULE 5                                   
                                                                               
                        BLOCKLISTING SIX MONTHLY RETURN                        



1. Name of company
Acambis plc

2. Name of scheme
Acambis 1995 Unapproved Share Option Scheme

3. Period of return: From 01 January 2003 to 30 June 2003

4. Number and class of shares(s)(amount of stock/debt security)not issued under
scheme at end of last period:
507,587

5. Number of shares issued/allotted under scheme during period:
765,501

Note: Additional block listing of 437,883 shares made during period

6. Balance under scheme not yet issued/allotted at end of period:
179,969

7. Number and class of share(s)(amount of stock/debt securities)originally
listed and the date of admission:
33,916,280 ordinary shares of 10p each

Date of admission: 30 November 1995


Please confirm total number of shares in issue at the end of the period in
order for us to update our records:
104,821,283



1. Name of company
Acambis plc

2. Name of scheme
Acambis 1996 Approved Share Option Scheme

3. Period of return: From 01 January 2003 to 30 June 2003

4. Number and class of shares(s)amount of stock/debt security) not issued under
scheme at end of last period:
533,981

5. Number of shares issued/allotted under scheme during period:
54,473

6. Balance under scheme not yet issued/allotted at end of period:
479,508

7. Number and class of share(s)(amount of stock/debt securities) originally
listed and the date of admission:
33,916,280 ordinary shares of 10p each

Date of admission: 30 November 1995


Please confirm total number of shares in issue at the end of the period in
order for us to update our records:
104,821,283



1. Name of company
Acambis plc

2. Name of scheme
Acambis 1995 Savings-Related Share Option Scheme

3. Period of return: From 01 January 2003 to 30 June 2003

4. Number and class of shares(s)amount of stock/debt security) not issued under
scheme at end of last period:
192,907

5. Number of shares issued/allotted under scheme during period:
148,336

6. Balance under scheme not yet issued/allotted at end of period:
44,571

7. Number and class of share(s)amount of stock/debt securities) originally
listed and the date of admission:
33,916,280 ordinary shares of 10p each

Date of admission: 30 November 1995


Please confirm total number of shares in issue at the end of the period in
order for us to update our records:
104,821,283

1. Name of company
Acambis plc

2. Name of scheme
Acambis 1999 Share Option Plan

3. Period of return: From 01 January 2003 to 30 June 2003

4. Number and class of shares(s) (amount of stock/debt security) not issued
under scheme at end of last period:
1,734,717

5. Number of shares issued/allotted under scheme during period:
200,372

6. Balance under scheme not yet issued/allotted at end of period:
1,534,345

7. Number and class of share(s)amount of stock/debt securities) originally
listed and the date of admission:
33,916,280 ordinary shares of 10p each

Date of admission: 30 November 1995

Please confirm total number of shares in issue at the end of the period in
order for us to update our records:
104,821,283

1. Name of company
Acambis plc

2. Name of scheme
OraVax 1990 Stock Incentive Plan

3. Period of return: From 01 January 2003 to 30 June 2003

4. Number and class of shares(s)amount of stock/debt security) not issued under
scheme at end of last period:
148,033

5. Number of shares issued/allotted under scheme during period:
4,327

6. Balance under scheme not yet issued/allotted at end of period:
143,706

7. Number and class of share(s) (amount of stock/debt securities) originally
listed and the date of admission:
33,916,280 ordinary shares of 10p each

Date of admission: 30 November 1995


Please confirm total number of shares in issue at the end of the period in
order for us to update our records:
104,821,283

1. Name of company
Acambis plc

2. Name of scheme
OraVax 1995 Stock Incentive Plan

3. Period of return: From 01 January 2003 to 30 June 2003

4. Number and class of shares(s)amount of stock/debt security) not issued under
scheme at end of last period:
150,000

5. Number of shares issued/allotted under scheme during period:
Nil

6. Balance under scheme not yet issued/allotted at end of period:
150,000

7. Number and class of share(s)amount of stock/debt securities) originally
listed and the date of admission:
33,916,280 ordinary shares of 10p each

Date of admission: 30 November 1995


Please confirm total number of shares in issue at the end of the period in
order for us to update our records:
104,821,283


Contact for queries: Elizabeth Brown
Address: Acambis plc, Peterhouse Technology Park, 100 Fulbourn Road, Cambridge
CB1 9PT
Name of person making return: Elizabeth Brown
Telephone: 01223 275300
Position of person making return: Company Secretary



END