MAC Appeals — Broken System, Broken Recovery

MAC (Maximum Allowable Cost) is the ceiling price a PBM will reimburse a pharmacy for a specific generic drug. Set weekly or monthly by PBM. Below-cost MAC pricing means the pharmacy loses money on every fill until the MAC updates.

The failure: MAC updates lag wholesale acquisition cost (WAC) changes. When generic manufacturers raise prices (which happens frequently for lower-volume generics), pharmacies pay the new WAC immediately but reimbursement stays at old MAC for weeks or months.

NCPA data: median independent pharmacy loses money on ~8% of Medicare Part D fills and ~15% of Medicaid fills due to below-WAC MAC pricing.

All major PBMs have formal MAC appeal processes. Pharmacies submit: (1) NDC of dispensed generic, (2) actual WAC paid (invoice documentation), (3) date of fill, (4) MAC reimbursement received.

PBM reviews and either (a) grants the appeal (retroactive reimbursement + updated MAC), (b) denies the appeal (no change), or (c) partially grants (updated MAC going forward but no retroactive recovery).

Typical timeline: 30-90 days per appeal. Success rate ~35% overall. Full retroactive recovery: ~20% of appeals. Partial (forward-only) recovery: ~15% of appeals.

Cost of appeal filing: 20-45 minutes of pharmacist time per NDC. For low-volume generics, appeal cost often exceeds potential recovery.

File appeal: high-volume generics where you dispense 200+ Rx/month at below-WAC. Recovery math works because volume × per-fill loss × appeal success rate exceeds the 20-45 minute filing cost.

Skip appeal: low-volume generics (< 50 Rx/month). Even at 35% success rate, recovery doesn't cover appeal cost.

Always appeal: any generic where you're losing $5+ per fill and dispensing 30+/month. The math almost always works.

Bulk appeals through PSAO: Most cost-effective route. PSAOs file MAC appeals in batches with pre-built documentation templates. Success rate is comparable to solo filing but cost per appeal is 10-20% of solo cost.