UCB: First quarter Zyrtec sales in the US.

Brussels, April 22, 2003 - Referring to today's announcement from Pfizer on its first quarter results, UCB confirms the US sales of Zyrtec grew 33% in dollars to $293 million in the first quarter, compared to the same period in 2002.

These revenue and NRx gains were achieved despite the recent significant decline in the Rx antihistamine market. With the availability of Claritin over-the-counter since December 2002, the Rx market has declined by 24% in year-to-date new prescriptions; further decline cannot be excluded.

Zyrtec's growth in this declining market can be attributed in part to strong performances by Zyrtec Syrup and Zyrtec-D 12 Hour. Zyrtec is now the only Rx or OTC antihistamine approved for use in infants as young as 6 months old.

Notwithstanding the level of the first quarter sales figure, in view of remaining uncertainties such as the evolution of the antihistamine market and the hayfever season, as well as the dollar/euro exchange rate, UCB remains cautious about the impact of the Zyrtec's first quarter sales figure on the full year's results.