The Intellectual Property Enterprise Court in London has found two patents related to the breast-cancer treatment drug Herceptin invalid, paving the way for generic versions of the drug to be marketed in the UK later this year. 

The patents concern the antibody trastuzumab, a cancer-fighting therapy developed by Genentech (a member of the Roche group) and sold under the Herceptin trade mark. Herceptin was a breakthrough in breast cancer treatment due to the way it targets the HER2 receptor, which is overproduced by cancer cells in about 20% of breast cancer patients. Hormones or other proteins can attach to the receptor, stimulating growth of the cancer cells and worsening the patient’s prognosis. 

In addition to the two patents at issue in these proceedings (EP 1 210 115 and EP 1 308 455), Herceptin is protected by an underlying patent (EP 0 590 058), whose term expires on 28 July 2014, having had the benefit of a Supplementary Protection Certificate (SPC), Hospira, which sells generic medicines particularly in the cancer field, wishes to sell a generic form of Herceptin in the UK after expiry of the SPC in July 2014. It did not challenge the ‘058 patent, but argued that the ‘115 and ‘455 patents were invalid for obviousness and/or insufficiency (the ‘115 patent), and lack of novelty and/or inventive step (the ‘455 patent). Both patents have already been held invalid by the European Patent Office and are currently before the Technical Board of Appeal. 

The Court in these proceedings also held both patents to be invalid. It held that the ‘115 patent, for a treatment regimen prescribing a specified loading dose and subsequent doses to be given every three weeks, would have been obvious to a clinician, given the prior FDA-approved weekly dosing regimen and the fact that a clinician would have consulted a pharmacokinetics expert. Alternatively, the patent did not adequately describe the invention and accordingly was invalid for insufficiency. 

The ‘455 patent, for a purified composition of the drug based on the level of acidic variants present, was found to be invalid due to lack of novelty over a prior Genentech application, which acted as an enabling disclosure of a similarly purified form of trastuzumab, and due to lack of inventive step following the prior art contained in slides presented by Genentech at a conference in April 1996. 

Hospira was also granted a declaration of non-infringement for five formulations of trastuzumab, with slightly higher levels of acidic variants than the limit contained in the second patent. 

With the last remaining enforceable patent on Herceptin expiring in July 2014, and pending any appeal, Hospira’s generic medicines could be available in the UK before the end of the year. 

The judgment can be read in full at: Hospira UK Ltd v Genentech Inc [2014] EWHC 1094 (Pat).