Survey: Many docs will be slow to switch to biosimilar mAbs

A large majority of oncologists around the world seem eager to switch their patients to biosimilar versions of ESA and G-CSF therapies once they become readily available, according to a new survey out from BioTrends Research Group. But there was a distinct hesitancy noted in the U.S. when the conversation turned to the first generation of biosimilars for the monoclonal antibodies like rituximab (Roche's ($RHHBY) $5.6 billion drug MabThera).

BioTrends' survey found that close to one in four French oncologists would take a "wait-and-see" attitude about the mAbs, which rose to a third in Germany and 42% to 45% in the U.S.

"74-80 percent of surveyed US oncologists expect to prescribe biosimilar G-CSFs and ESAs within one year of launch," said Biosimilars Advisory Services' Director, Andrew Merron, Ph.D. "However, only 54-61 percent of surveyed US oncologists expect to prescribe a biosimilar monoclonal antibody within the same time frame."

The ESAs have long been considered the low-hanging fruit among new biosimilar developers, with a long track record and an easily defined mode of action. But the older mAbs like rituximab, trastuzumab, cetuximab and bevacizumab represent some big upside for the emerging industry. Any hesitancy on the part of oncologists to switch over to biosimilars would translate into billions of dollars of retained revenue for the pharma giants which control them. The caution underscores the slow arrival of biosimilar competition, in marked contrast to the rapid blitz felt by the small molecule crowd.

Small price reductions may also have limited appeal when there's a preferred delivery method. A subcutaneous version of MabThera priced at the same level as IV MabThera would be preferred over an IV biosimilar priced at a 10% discount for the maintenance setting for follicular lymphoma. 

Despite the predicted initial caution, BioTrends says it expects that the market for biosimilar mAbs will near $5 billion by 2021.

- here's the press release