The likelihood of a biosimilar version of Herceptin reaching the UK market in the next few months has increased dramatically after the High Court overturned two key patents on Roche's breast cancer blockbuster.

The ruling, which stated that the patents (relating to dosage and composition) were invalid, is a major boost for Hospira, the US firm which brought the case against Roche's Genentech unit. The patents on Herceptin (trastuzumab) for HER2 positive breast cancer expire in Europe at the end of July and Hospira will be ready to launch in the UK.

Hospira has been working with Celltrion to develop a number of biosimilars and the latter has already launched their version of Herceptin, called Herzuma, in its home market of South Korea. The firms are already marketing a biosimilar of Johnson & Johnson's and Merck & Co's anti-inflammatory Remicade (infliximab) in Europe, as Inflectra.