Medicare AdvantagePrior AuthMedium impact
Enhertu (fam-trastuzumab deruxtecan-nxki) (Revised)
Humana·FL, KY, SC · Oncology·Medicaid
Effective date
Aug 26, 2026
We identified it
Aug 26, 2026
Summary
Humana revised its Enhertu (fam-trastuzumab deruxtecan-nxki) pharmacy coverage policy effective August 26, 2026, expanding indications and clarifying prior authorization requirements across Medicare, Medicaid-Florida, Medicaid-Kentucky, and Medicaid-South Carolina. The policy now covers seven distinct cancer indications with specific HER2 status requirements, treatment sequencing rules, and cycle limits. Billing teams must verify member eligibility against detailed clinical criteria before claim submission to avoid denials.
Action Required
By August 26, 2026: Billing team must update prior authorization workflows in billing software to enforce Enhertu (J9261) coverage criteria for all seven indications listed in this policy. Create separate PA decision trees for: (1) HER2-Positive Early Breast Cancer (neoadjuvant: max 4 cycles + THP; adjuvant: max 14 cycles with documented residual disease), (2) HER2-Positive Unresectable/Metastatic Breast Cancer (first-line with pertuzumab OR monotherapy after prior anti-HER2 therapy), (3) HER2-Low Breast Cancer (metastatic, prior chemotherapy or endocrine therapy failure), (4) HER2-Ultralow Breast Cancer (metastatic, HR-positive, endocrine therapy failure), (5) Gastric/GEJ Adenocarcinoma (prior trastuzumab required), (6) HER2-Mutant NSCLC (prior systemic therapy required), and (7) HER2-Positive Solid Tumors (IHC 3+, prior treatment, no alternatives). Providers must document HER2 status (IHC/ISH results), cancer stage, prior treatment history, and treatment sequencing. Deny claims for: members exceeding cycle limits (4 for neoadjuvant breast cancer, 14 for adjuvant breast cancer), disease progression on Enhertu, or combination therapy outside approved first-line setting for metastatic breast cancer. Update encounter forms and prior auth request templates to require documentation of all clinical criteria. Train billing staff and prior auth personnel on new indications and cycle restrictions. Applied to: Medicare, Medicaid-FL, Medicaid-KY, Medicaid-SC lines of business.