Eli Lilly’s Lantus biosimilar is waiting to edge into the US market, Hospira is developing a lookalike for Roche’s Lucentis, and an FDA panel endorsed a biosimilar of Amgen’s Neupogen, but a study by the Tufts Center for the Study of Drug Development indicates it is going to take some time before biosimilars unseat branded biologics.

Joshua Cohen, the study’s author, explained in the nonprofit research group’s announcement that trust is a key selling hurdle for biosimilars, regardless of a regulatory approval or lower prices. The group receives about 40% of its funding from industry.

“Lack of familiarity with biosimilars by physicians may hinder their use, as has been the case in Europe, where 17 biosimilars have been approved since 2006,” he said in the study’s announcement.

Cohen’s research team also found that manufacturers may waste their time trying to convince doctors to switch patients from a branded to a non-branded biologic. While 66% of the 42 surveyed US doctors said they would consider prescribing lookalikes for new patients, 33% said they would not switch patients from a branded to an unbranded biosimilar.