UK biotechnology company, Antisoma, saw its shares marginally boosted on the London Stock Exchange this morning after winning European orphan drug designation for its kidney and pancreatic cancer drug, code-named AS1411.

AS1411 is an aptamer drug that binds to the protein nucleolin, which is found on the surface of cancer cells, and is internalised, and already has similar status in the USA for these tumour types. In the States orphan drugs are entitled to seven years’ market exclusivity if approved in the given indication(s), while in Europe it is 10 years.

Clinical data to date show two out of three kidney cancer patients treated with AS1411 had long-term stable disease and one a near-complete response. The trial is being extended to include additional patients, with data expected to be unveiled later on this year, and Antisoma has said it will push for fast-track development of the compound in this use. Meanwhile, the firm is also exploring the use of AS1411 in pancreatic cancer, alongside other solid and blood cancers, to determine which should be given priority for Phase II trials.

The UK biotech will certainly be hoping that AS1411 scores a win in later-stage trials, particularly in kidney cancer, on the back of a £7.1 million net loss for the year ending June 2005 from £600,000 in 2004, reflecting a substantial fall in revenues and greater investment in its clinical pipeline.