TNF Inhibitor denied as duplicate or overlapping therapy by Highmark?

Highmark uses Prime Therapeutics PBM. Adalimumab biosimilar preferred (Cyltezo/Hyrimoz/Yusimry). Step therapy through preferred biosimilar required for new starts; existing patients on Humira may grandfather.

Highmark Continuity of Care provisions — 90-day grandfather for established therapy. Cite Prime Therapeutics PA exception process. ACR 2019 Position Statement opposes non-medical switching of stable patients.

## Why Highmark May Deny a TNF Inhibitor as "Duplicate Therapy"

A duplicate-therapy denial means Highmark's claims system has identified that the patient is already receiving another drug in the same therapeutic class — in this case, another biologic or targeted immunomodulator — and the plan does not cover two agents from the same class simultaneously. For TNF inhibitors, this typically occurs when a patient is transitioning from one biologic to another but prescriptions overlap, or when a prescriber has ordered combination biologic therapy (e.g., a TNF inhibitor plus another biologic mechanism) that the plan treats as duplicative.

## Why This Denial Is Often Appealable

Duplicate-therapy denials frequently result from billing timing rather than genuine co-administration. If the prior biologic was discontinued before the new one began, pharmacy records and prescribing dates can establish the timeline. In cases where combination therapy is genuinely intended, the prescriber can document the clinical rationale — for example, a bridging period or a medically recognized combination use — and appeal on medical-necessity grounds. Highmark must evaluate the actual clinical record, not just overlapping claim dates.

## Your Federal Appeal Rights

• Internal appeal: File your appeal within the deadline in your denial notice. Highmark must decide pre-service non-urgent appeals within 30 days and post-service appeals within 60 days.
• External review (ACA §2719): After exhausting the internal process, request IRO external review within approximately four months of the final denial. The IRO's determination is binding on Highmark.
• Expedited review: If your health would be seriously jeopardized by delay, request expedited internal and external review; decisions are typically issued within 72 hours.
• ERISA §503: If coverage is through an employer plan, you are entitled to a full-and-fair review with access to all documents used in Highmark's decision.

## Documentation to Gather

1. Prescription and dispensing records for both drugs — exact fill dates, days' supply, and discontinuation dates to establish whether co-administration actually occurred. 2. Chart notes confirming the transition timeline — physician documentation showing when the prior biologic was stopped and when the new one was started. 3. Prescriber letter addressing the overlap — if the dates genuinely overlapped, a letter explaining the clinical reason (washout period, transition management, etc.) and confirming that concurrent administration was not the intent or was clinically justified. 4. Highmark's duplicate-therapy policy — obtain the most recent version of Highmark's relevant medical or drug policy so the appeal can respond to each stated criterion.

## Criteria-Mapping Strategy

Map the claim dates and fill records onto a simple timeline showing when each biologic was active. If there was genuine overlap, pair each day of overlap with the clinical documentation justifying it. If the overlap was a billing artifact, the timeline itself may be sufficient to resolve the denial. Attach supporting prescribing instructions and any pharmacy communication confirming the discontinuation of the prior agent. A concise, factual timeline is more persuasive than a narrative explanation in duplicate-therapy appeals.