SkyePharma has agreed to end its development alliance with North American partner Endo Pharmaceuticals for Propofol IDD-DTM , an injectable anaesthetic and sedative.

The UK firm licensed the product to Endo in December 2002 but, said it is now evaluating its options worldwide for this product, which remains under strategic review.

SkyePharma would have been responsible for the cost of Phase III development for Propofol IDD-DTM, estimated to be up to $30 million, but could have received up to $45 million in additional milestone payments from Endo if the product had been approved by the US Food & Drug Administration, depending on eventual labelling for the drug. The company also stood to receive a share of Endo's sales of Propofol IDD-DTM that could have varied between 30% and 60%, out of which SkyePharma would have paid for manufacturing costs.

Propofol IDD-DTM is designed to avoid using a preservative in the anaesthetic’s formulation to prevent microbial contamination. The product successfully completed Phase II trials in 2004.

SkyePharma said termination of the Propofol collaboration does not affect its partnership with Endo for DepoDur, a sustained release version of morphine.