Amgen and Allergan have announced positive top-line results from a pivotal clinical study of their rituximab biosimilar version of Roche’s blockbuster biologic Rituxan to treat patients with non-Hodgkin's lymphoma.

Sandoz expects to bring an expedited appeal against a US district court’s finding that two patents protecting Amgen’s Enbrel etanercept brand until 2028 and 2029 are valid. 

INFOGRAPHIC: A relatively small number of relatively costly drugs account for a sizable proportion of pharma industry revenues. But what are its biggest golden eggs, how reliant are companies on those products, and how has the situation evolved over time?