This gets cited here weekly, usually second-hand, so it is worth setting out what it does and does not establish.
Denials are usually procedural rather than clinical, and the order that works reflects that. Get the denial reason in writing, because it names the criterion you failed. Then supply the documentation that criterion asks for — usually documented BMI with a comorbidity, or a failed prior therapy. Then appeal, and ask for a peer-to-peer review, because a prescriber talking to a reviewing clinician resolves a large fraction of denials that written appeals do not. Manufacturer copay assistance is separate and applies mainly to commercial insurance, and patient assistance programmes are means-tested rather than a discount.
Where I think it is weakest: the subgroup findings are the part I trust least — with enough subgroups something is always significant, and these were not all pre-registered.
The narrow version of the question is what actually works on a prior-authorisation denial, as opposed to the list of things that sound like they should work. I have searched first, so if this is covered somewhere point me at it and I will read it.
Note on sourcing:
Figures above are from the primary publication rather than the press summary. If a number here disagrees with one you have, post yours and we will work out which of us is reading a secondary source.