X0202 4 2005-07-27 1 0000885259 TRANSKARYOTIC THERAPIES INC TKTX 0001308655 Kirby Neil C/O TRANSKARYOTIC THERAPIES, INC. 700 MAIN STREET CAMBRIDGE MA 02139 0 1 0 0 Sr. VP- Strategic Prod. Dev. Stock Option (right to buy) 23.79 2005-07-27 4 D 0 15000 13.21 D 2015-03-24 Common Stock 15000 0 D Stock Option (right to buy) 21.74 2005-07-27 4 D 0 40000 15.26 D 2014-11-11 Common Stock 40000 0 D Stock Option (right to buy) 10.62 2005-07-27 4 D 0 15000 26.38 D 2014-03-24 Common Stock 15000 0 D Stock Option (right to buy) 9.76 2005-07-27 4 D 0 4500 27.24 D 2013-06-11 Common Stock 4500 0 D Stock Option (right to buy) 5.84 2005-07-27 4 D 0 18000 31.16 D 2013-03-28 Common Stock 18000 0 D This option, which was granted on March 24, 2005 and provided for vesting in three equal installments beginning on March 24, 2006, was cancelled pursuant to a merger agreement among the Issuer, Shire Pharmaceuticals Group plc and Sparta Acquisition Corporation, dated April 21, 2005, in exchange for a cash payment of $198,150, representing the excess of $37.00 over the per share exercise price of the option multiplied by the number of shares subject to the option, whether vested or unvested. This option, which was granted on November 11, 2004 and provided for vesting in three approximately equal annual installments beginning on November 11, 2005, was cancelled in the merger in exchange for a cash payment of $610,400, representing the excess of $37.00 over the per share exercise price of the option multiplied by the number of shares subject to the option, whether vested or unvested. This option, which was granted on March 24, 2004 and provided for vesting in three equal annual installments beginning on March 24, 2005, was cancelled in the merger in exchange for a cash payment of $395,700, representing the excess of $37.00 over the per share exercise price of the option multiplied by the number of shares subject to the option, whether vested or unvested. This option, which was granted on June 11, 2003 and provided for vesting in four equal semi-annual installments beginning on December 11, 2003, was cancelled in the merger in exchange for a cash payment of $122,580, representing the excess of $37.00 over the per share exercise price of the option multiplied by the number of shares subject to the option, whether vested or unvested. This option, which was granted on March 28, 2003 and provided for vesting in four equal semi-annual installments beginning on September 28, 2003, was cancelled in the merger in exchange for a cash payment of $560,880, representing the excess of $37.00 over the per share exercise price of the option multiplied by the number of shares subject to the option, whether vested or unvested. /s/ Neil Kirby 2005-07-27