The figures, for anyone assembling their own picture. For anyone assembling their own picture: Tmax is one to three days, terminal half-life about 165 to 170 hours, steady state at four to five weeks, and subcutaneous bioavailability near 89%. Those four numbers explain most of the questions people ask about timing.

Happy to go further on any of that.

Following on from Dr.RaviCardio — and this may be the naive question:

How much of the between-person variation is pharmacokinetic and how much is just adherence measured badly?

quinn_sf said:

For anyone assembling their own picture: Tmax is one to three days, terminal half-life about 165 to 170 hours, steady state at four to five weeks, and…

Coming at quinn_sf’s question from a different direction. Albumin binding above 99% is the whole reason weekly dosing works, and it is also why the trough matters more than the peak. People who dose late are not losing a peak, they are letting the trough fall, and the appetite effect tracks the trough.

That is the short version; the long version is somebody else's post.

OP back with an update, since a thread like this is useless without one.

Following this thread I went back and re-read the extension data properly. The point about trough rather than peak explains the pattern I was seeing on day six, which I had been blaming on the vial.

anna.melb_AU said:

Albumin binding above 99% is the whole reason weekly dosing works, and it is also why the trough matters more than the peak.

anna.melb_AU has the substance of this right. The condition it depends on is worth stating. The dose-response is real but shallow at the top. Across STEP 1 and STEP 4 the gap between 1.7mg and 2.4mg is a couple of percentage points of body weight on average, and the average is carrying a wide spread — plenty of people at 1.7mg sit above the 2.4mg mean. If a dose is working and tolerable, "working" is the relevant variable, not "maximal".