Medicines Co. ( MDCO) slashed 2005 guidance, saying sales of its blood-clotting agent Angiomax fell short of goals. The Parsippany, N.J., company also agreed with its largest wholesalers to enter into new fee-for-service arrangements that Medicines Co. said should improve its margins, create more predictable buying patterns, and result in reductions in wholesaler inventories. Even so, its shares fell 20% in late trading Wednesday. The company said it expects to lose about $10 million for the year on revenue of $150 million. Previously, Medicines Co. had forecast earnings of roughly $27 million on sales of $195 million or so. The company said it would lose $10 million for the third quarter alone on sales of $30 million. Analysts surveyed by Thomson First Call were looking for an 8-cent-a-share profit on revenue of $45 million. "In a sluggish cath lab market, Angiomax hospital sales have grown by 42% this year compared to last year, but we are about $19 million below our ambitious hospital sales plan for 2005," said CEO Clive Meanwell. "In addition, we believe that wholesaler changes will strengthen our future performance and that the benefits outweigh the short-term pain." Late Wednesday, Medicines Co. shares fell $4.32 to $17.61.