Medeva PLC
25 January 2000

LETTER TO: COMPANY ANNOUNCEMENTS OFFICE

MEDEVA PLC ('THE COMPANY')
--------------------------
NOTIFICATION OF INTEREST OF DIRECTORS
-------------------------------------

The Company received notification today that Medeva directors have today sold
Celltech Shares at a price of GBP 7.50 per Celltech Share as shown below,
conditional upon the merger between Celltech Chiroscience plc (which has been
renamed Celltech Group plc ('Celltech')) and Medeva PLC ('Medeva') becoming
effective and the listing of Celltech 50p Ordinary Shares ('Celltech Shares'):

Director                     Dr W Bogie    G Watts           MG Hardy

No. of Celltech                  441,014   178,466             223,104
Shares sold      (and in addition 28,900
                           sold by wife)

No. of Celltech                   34,445     4,099               2,949
Shares which will be
held following the
sale and exercise
of the share options
described below*

No. of options over              170,646   108,015              53,754
Celltech Shares
which will be held
following the sale and
the exercise of the
share options
described below*


Director                    Dr MD Young                    J Ferguson

No. of Celltech                  140,046                        80,954
Shares sold      (and in addition 52,054
                           sold by wife)

No. of Celltech                    6,800                           344
Shares which will be
held following the
sale and exercise
of the share options
described below*

No. of options over               91,732                        41,797
Celltech Shares
which will be held
following the sale and
the exercise of the
share options
described below*


The Celltech Shares being sold arise from the exercise of options or will
arise from the exercise of options following completion of the merger under
Medeva's share option scheme as follows:

Director                     Dr W Bogie    G Watts            MG Hardy

No. of Medeva                    678,600         -             314,591
Options exercised on
the date of this
announcement

No. of Medeva                    703,500   524,900             341,600
Options anticipated to
be exercised on the
day following the day
on which the merger
becomes effective

Exercise price range            nil-145pnil-212.5p            nil-201p
per Medeva Option


Director                     Dr MD Young                    J Ferguson

No. of Medeva                    153,100                             -
Options exercised on
the date of this
announcement

No. of Medeva                    411,900                       238,100
Options anticipated to
be exercised on the
day following the day
on which the merger
becomes effective

Exercise price range            nil-178p                  96.5p-147.5p
per Medeva Option

* Calculated using the exchange ratio of 0.34 Celltech Shares or Options for
each Medeva Share or Option respectively.


FROM: MEDEVA PLC