Underfire Amgen, which has suffered a torrid time of late over questions about the safety of its top-selling anaemia drugs Aranesp and Epogen, has leapt into the market to snap up Ilypsa, a privately-held San Francisco –based biotechnology company.

Under terms of the agreement, Amgen will pay $420 million in cash to acquire Ilypsa, which does not have any products on the market yet, although it does have a promising compound, ILY101, a phosphate binder for the treatment of hyperphosphatemia in chronic kidney disease patients on haemodialysis. The drug has just successfully completed Phase II studies.

George Morrow, executive vice president of global commercial operations at the US biotechnology giant, said that “Ilypsa and ILY101 are a strategic fit for Amgen's nephrology portfolio and further demonstrate our commitment to explore, develop and commercialise promising therapies that help in the fight against kidney disease". The deal has gone down well with analysts who feel that this acquisition could be first of many by cash-rich Amgen, especially given the recent events surrounding the firm's erythropoiesis-stimulating agents Aranesp (darbepoetin alfa) and Epogen (epoetin alfa).

Days after a US Food and Drug Association advisory committee recommended a further strengthening of the warning labels on the drugs last month, the Centers for Medicare & Medicaid Services proposed limiting payments for the two in response to safety concerns. Given that Aranesp and Epogen accounted for nearly half the company's revenue last year and 60% of its profit, the effect of that measure is clear and Amgen suffered a further blow when the European Medicines Agency's Committee for Medicinal Products for Human Use recommended that the colorectal cancer drug Vectibix (panitumumab) should not be approved.

Amgen has several high-profile drugs under development, including an osteoporosis treatment that has had impressive results in early clinical trials, but it is not likely to hit the market for at least two years.