Where volume actually moves your rate
On 503A lines, volume helps because you can consistently route high-throughput SKUs to the lowest comparison tile — and re-check when pharmacies update rates. Smart routing may automate that shift, but you still need to confirm the pharmacy fulfilling your GLP-1 refills today is the same one you priced your patient programs on last quarter. Ask whether preferred pharmacy selections lock a rate or re-open comparison each order.
On 503B bulk, volume pricing is more traditional: larger in-office orders on standardized strengths may tier down. That path suits clinics stocking office-use vials more than patient-specific titration ladders. If your formulary is mostly 503A semaglutide and tirzepatide shipped to patients, marketplace competition matters more than 503B bulk tiers — validate both if you use each channel.