Deutsche expects sales of Exanta to reach $630m (£402m) by 2006, or 3% of group sales, but there is concern over the impact of Exanta on the liver. Merrill says AZ shares are now at a 50% premium to the global drugs sector. Warburg has also raised Celltech, up 21 3/4p at 297 3/4p, from neutral to buy and repeated its 360p target price. The shares have been dull since it made a bid for Oxford Glycosciences, steady at 193 1/2p.