The flags are out at Amgen after a court voted against Roche and effectively blocked the latter from launching Mircera, a potential competitor to the US biotechnology giant’s best-selling anaemia drugs Epogen and Aranesp.

A jury in a US district court in Boston has ruled that Roche's Mircera (continuous erythropoietin receptor activator) for anaemia infringes on 11 Amgen erythropoietin (EPO) patent claims. The company said that it is pleased with the jury's verdict and will now seek an injunction to prevent Roche from selling its product in the USA and an injunction hearing is scheduled for November 15.

Amgen stated that in addition to infringing its EPO patents, it “firmly believes Roche's peg-EPO product provides no clinical or patient benefit over Amgen's innovative therapies”, namely Epogen (epoetin alfa) and Aranesp (darbepoetin alfa). This is not a view shared by the Swiss healthcare giant, however.

Roche said it is currently evaluating its legal options, including the possibility of an appeal and insisted that all of Amgen’s patents for epoetin asserted against Roche are invalid and not infringed, adding that “the facts and the law support that position”. William Burns, head of its pharmaceuticals unit, said the verdict is disappointing “because in the end, it is US patients with chronic kidney disease who lose. Amgen has had an extended monopoly for the last 20 years in the USA blocking new therapeutic options to treat anaemia from being introduced”.

Roche has already received an approvable letter from the US Food and Drug Administration for Mircera, for the treatment of anaemia associated with chronic kidney disease, and a final decision is expected on November 14, while the drug has been recently launched in Austria, Sweden, Germany and the UK. The Basel-based group said that studies have shown that Mircera corrected and maintained haemogloblin levels as well as existing erythropoiesis-stimulating agents (ESAs) but with fewer injections. Nevertheless, if the aforementioned injunction is granted, Roche may not be able to get Mircera onto to the US market until 2013.

The news is a massive boost for Amgen which has suffered a miserable run of late, most notably through plans for Medicare to restrict reimbursement of ESAs used in patients with chemotherapy-associated anaemia. Analysts noted that the firm is still under pressure to find replacements for the anaemia drugs and there were fears that Mircera could capture up to 15% of US sales for chronic kidney disease, by undercutting the price of Amgen's drugs. That fear has abated for the time-being.