biojuice

The WSJ reports that Genentech is restricting the availability of Avastin to compounding pharmacies in an effort to prevent the re-formulation and use of Avastin to treat wet macular degeneration. Irv Arons has written a fascinating series of posts about the Avastin/Lucentis debate.

Lucentis is derived from Avastin, but they are different molecules and not just different formulations of the same drug. Lucentis (Ranibizumab) is a 48kD protein consisting of a humanized Fab fragment; Avastin (Bevacizumab) is an 148kD IgG1 antibody. It’s not at all obvious that they’re going to work exactly the same when injected into an eye, and the clinical trials comparing them are still ongoing.
That a significant number (50%?) of patients and doctors are willing to potentially compromise suggests that the Lucentis price is way too high (at least for some patients) given its advantages, perceived or otherwise. Presumably there is some point at which the benefits of a molecule and formulation optimized for the eye is worth some extra expense if it works better. On the other hand, using Avastin is apparently effective, widely used, and seems to be safe, based on a grass-roots safety monitoring study, the International Intravitreal Bevacizumab (Avastin) Safety Survey.

It seems clear that there is some price-gouging going on, but there are also legitimate reasons to prefer Lucentis, and the safety concerns are logical, even if they may be overstated. I wonder whether there is any possibility for a company to be held liable for problems resulting from off-label use of a drug — if so, that does partially justify taking steps to discourage off-label uses.