Drug Coverage Lookup

See how a prescription drug is placed across Medicare Part D plan formularies — tier, prior authorization, step therapy, and quantity limits, counted per unique plan.

Tybost (Cobicistat)

Cytochrome P450 3A Inhibitor

Not found in this Part D formulary dataset

The drug identity is verified, but it was not found on any Medicare Part D formulary in this dataset (data current through 2026-08-31). The dataset excludes employer and PACE plans.

The drug identity is verified, but it does not appear on any Medicare Part D formulary in this dataset (current through 2026-08-31). The dataset excludes employer and PACE plans. Confirm with your plan and ask about a formulary exception; meanwhile compare cash prices.

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If it is not covered by your plan, a discount price may be your best option.

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Source: CMS Monthly Prescription Drug Plan Formulary and Pharmacy Network Information — data current through 2026-08-31 (CMS release 2026-08-26, refreshed monthly). Dataset-wide plan-year formulary placement, not a guarantee of your individual benefit — confirm with your plan or pharmacist.

Data: CMS Monthly Part D formulary files · FDA/RxNorm drug identity · CMS NADAC pricing — CMS Part D formulary data current through 2026-08-31 · source

Machine access — this tool is available as structured data for AI assistants and agents:
GET https://insurewith.ai/tools/drug-coverage/data.json?drug=cobicistat