[s1artibartfast]

This is a really good summary. It is mentioned by worth reiterating that evergreening does not prevent generic competition of the origional formulation or configuration. I think it is a bit of a misnomer to refer to these as patent lifetime extensions.

Having spend decades work with pharma companies, I agree that one of the main issues is missaligned incentives between patients and PBMs/health plans.

Bad patents are hard to quantify but a big part of picture. Should the patent office rejected Flovent + HFA as obvious? Another example would be Novarits patents on VEGF in silicone syringes. Litigating a global patent fight with Pharma companies with billions at stake is a huge barrier. The best way to prevent this IMO is more disgression in initial patent issue.

[ekr____]

Original author here: Yeah a lot of the evergreening techniques (chiral switch, etc.) don't prevent anyone from getting the original, though of course doctors may try to switch you. The inhaler thing is double bad because of the CFC ban.

I didn't dig into the details of the fluticasone HFA switch, but my impression is that while it's obvious to replace the propellant, apparently you do need to do some engineering (e.g., on the nozzle) to make it work right. I don't know enough about what they actually had to do to know if the patent should have been granted or not.