A new survey (BioTrends Research) of oncologists in the US and around the world indicated that 42-45% on US docs would take a "wait and see" attitude toward prescribing biosimilar mAbs when they first become available. This contrasts with 25% docs in France and 33% docs in Germany for example. The same US docs also said that 75-80% of them would prescribe biosimilar ESAs or G-CSF when available.
So US docs are being more conservative in their approach with the mAbs to treat cancer -- like rituximab, trastuzumab, cetuximab and brevacizumab. They apparently want to see how these drugs perform in patients post-approval (just not their patients first!).
I'd find that surprising at first but it really isn't. Medicine is pretty conservative field -- afterall is based on "do no harm" as a first precept. What personal experience I have with a decision like this does mirror this behavior. My daughter is on Enbrel for AS. Her rheumatologist basically looked at the innovator drugs Enbrel, Humira and Simponi -- all anti-TNF alpha drugs, all approved from well known companies -- and opted for Enbrel as his first choice.
Why? Because he had the greatest clinical experience with it. Most of his patients on this drug class had seen it. It had been approved first and was around the longest. Also, he has a family member on it who has experienced success with it. Bascially, given the choice he'd follow the timeline of approval -- Enbrel, Humira and then Simponi -- given no other information. It's logical. Let experience be my guide. And that's with approved, innovator drugs. So it's not surprising that the first biosimilars may face some skepticism until they get some experience in the real world -- kind of like a new job applicant. See Fierce Biotech.
The only thing that is likely to change this dynamic in my view is a profound price difference between the two drug types and some powerful government or third party "incentives" (positive or negative) to pick a cheaper choice.
Posted by Bruce Lehr Oct 29th 2012.