Antisoma, the UK biotechnology company, has snubbed Nomura, which it has used for several deals in the past, and appointed SG Cowen sole financial adviser and corporate broker to help take it forward in the US market.

According to Charles Spicer, a director in Nomura's healthcare investment banking team, Antisoma never had a formal arrangement with Nomura to be adviser, and the company did not previously have a broker.