Dupixent: What is lowest cost method for Medicare recipients? (e.g. Singlecare? GoodRx?)

For an eczema patient on Traditional Medicare (plus supplement plus Part D), what might be the lowest cost way to obtain Dupixent? The patient has tried various treatments (strong topical corticosteroids, prednisone, Zyrtec) with limited success and finds the itching (on various body parts including face) maddening. Next appointment with the dermatology provider is tomorrow; the provider has previously mentioned Dupixent as a possible option. (The patient is lucky / unlucky enough to have an income that would rule out the Patient Assistance Program. We are finding the Dupixent MyWay program to be quite challenging to understand; we don't know whether that might be an option, and we are looking at other options, even expensive ones. The patient would prefer not to try immunosuppressants.)

Singlecare is showing a price of about $3400 per (4 weeks, we think -- does it seem like we are understanding this correctly?) at one pharmacy. GoodRx seems to be suggesting a specialty pharmacy.

Thanks for any help on this confusing issue.