A US federal appeals court has ruled that Swiss drugmaker Novartis can begin selling Zarxio, its lower-cost generic version of an Amgen drug, on the US market starting in September. This thwarts a bid by the US biotech company to further delay the launch.

In what was called a landmark decision, the US Food and Drug Administration (FDA) in March gave Novartis the green light to sell the generic version of Amgen’s Neupogen – used to boost blood cells in cancer patients. It was the first biosimilar to be approved by the regulatory agency.

A dispute subsequently ensued over the length of the notice the producer of a biosimilar must give to the original drugmaker after receiving FDA approval before starting the marketing process.

In its Jul. 21 ruling the court said companies marketing new biosimilars must give 180 days advance notice. Novartis had argued that the notice could be given prior to FDA approval.

The Swiss company began selling its version of the drug in Europe – where it is called Zarzio – in 2009. Novartis also markets two other biosimilar drugs in about 60 countries.