Viva Health Gamifant Coverage & Prior Auth

Coverage Criteria for Gamifant (emapalumab-lzsg)

Initial Therapy

Covered when ALL of the following universal and indication-specific criteria are met

Universal safety and monitoring: Patient has been evaluated and screened for latent tuberculosis (TB) prior to initiating treatment and will receive ongoing TB monitoring; providers will monitor and consider prophylaxis for Herpes Zoster, Pneumocystis jirovecii, and fungal infections; patient does not have an active infection, including infections favored by IFN-γ neutralization (e.g., mycobacterial infections, Histoplasma Capsulatum); and therapy will not be administered concurrently with live or live attenuated vaccines.

Primary HLH diagnostic options: Either (1) definitive diagnosis of primary HLH based on identification of biallelic pathogenic gene variants or a family history consistent with primary HLH; OR (2) at least five of the following eight documented criteria: prolonged fever (>7 days); splenomegaly; cytopenias affecting ≥2 of 3 lineages (hemoglobin <9 g/dL, platelets <100 x 10^9/L, neutrophils <1 x 10^9/L); hypertriglyceridemia (fasting triglycerides >3 mmol/L or ≥265 mg/dL) and/or hypofibrinogenemia (≤1.5 g/L); hemophagocytosis in bone marrow, spleen, or lymph nodes without evidence of malignancy; low or absent NK-cell activity; ferritin ≥500 mcg/L; soluble CD25 ≥2400 U/mL.

Primary HLH treatment status: Patient has active primary disease that is refractory, recurrent, or progressive during conventional HLH therapy unless intolerant; patient has NOT received hematopoietic stem cell transplant (HSCT); and emapalumab will be used in combination with dexamethasone (patients may continue oral cyclosporine A or intrathecal methotrexate/glucocorticoids if already receiving them).

Continuation/Renewal Therapy

Renewal/continuation covered when ALL of the following are met

Ongoing universal criteria: Patient continues to meet the universal and indication-specific criteria (including concomitant therapy requirements) and there is absence of unacceptable toxicity (examples: serious infections including mycobacteria, Herpes Zoster, Histoplasma Capsulatum; infusion-related reactions); AND patient is receiving ongoing monitoring for adenovirus, EBV, and CMV as clinically indicated.

Primary HLH renewal response criteria: Patient continues to require therapy (e.g., until HSCT or unacceptable toxicity) AND has experienced one of: complete response (normalization of all HLH abnormalities: no fever, no splenomegaly, neutrophils >1 x 10^9/L, platelets >100 x 10^9/L, ferritin <2,000 μg/L, fibrinogen >1.50 g/L, D-dimer <500 μg/L, normal CNS symptoms, no >2-fold worsening of sCD25); OR partial response (normalization of ≥3 HLH abnormalities, including CNS abnormalities); OR improvement defined as ≥50% improvement from baseline in ≥3 HLH clinical and laboratory criteria; OR meets dose-escalation criteria based on listed clinical/laboratory parameters (persistent/recurrent fever; platelet or neutrophil thresholds or declines; ferritin criteria; worsening splenomegaly; coagulopathy thresholds).

HLH/MAS renewal criteria: Patient continues to require therapy AND either achieved complete response defined by VAS ≤1 cm plus seven laboratory endpoints (WBC and platelets above LLN; LDH, AST, ALT <1.5×ULN; fibrinogen >100 mg/dL; ferritin decreased ≥80% from baseline or <2000 ng/mL) OR has unsatisfactory improvement and requires dose escalation (per dosing/administration limits).

Concurrent administration with live or live attenuated vaccines is prohibited. This is a universal safety requirement and must be confirmed before initiating therapy and documented in the medical record.

Medicare Part B Covered Diagnosis Codes: N/A. This appendix contains no Medicare-specific covered diagnosis codes; Medicare coverage is governed by CMS manuals, NCDs/LCDs and LCAs where applicable.

Use in patients with active infections that are favored by interferon-γ neutralization (for example, mycobacterial infections or Histoplasma capsulatum) is contraindicated and would be considered not appropriate for coverage. Providers must screen for and document absence of active infection before initiating therapy and monitor for infections during treatment.

Coding — HCPCS, NDCs, and ICD-10 Codes

Covered HCPCS CodesHCPCSCovered

J9210

Injection, emapalumab-lzsg, 1 mg; 1 billable unit = 1 mg

NDCsNDC

66658-0501-xx	Gamifant 10 mg/2 mL single-dose vial
66658-0505-xx	Gamifant 50 mg/10 mL single-dose vial
66658-0510-xx	Gamifant 100 mg/20 mL single-dose vial
66658-0522-xx	Gamifant 50 mg/2 mL single-dose vial
66658-0523-xx	Gamifant 100 mg/4 mL single-dose vial
66658-0524-xx	Gamifant 250 mg/10 mL single-dose vial
66658-0525-xx	Gamifant 500 mg/20 mL single-dose vial

Covered ICD-10 Diagnosis Codes (excerpt)ICD-10Covered

D76.1	Hemophagocytic lymphohistiocytosis
D89.40	Mast cell activation, unspecified
D89.49	Other mast cell activation disorder
M06.1	Adult-onset Still's disease

Covered ICD-10 Codes (selected)ICD-10Covered

D76.1	Hemophagocytic lymphohistiocytosis
D89.40	Mast cell activation, unspecified
D89.49	Other mast cell activation disorder

Covered ICD-10 Codes (M08-series juvenile arthritis examples)ICD-10Covered

M06.1	Adult-onset Still's disease
M08.0A	Unspecified juvenile rheumatoid arthritis, other specified site
M08.011	Unspecified juvenile rheumatoid arthritis, right shoulder
M08.012	Unspecified juvenile rheumatoid arthritis, left shoulder
M08.019	Unspecified juvenile rheumatoid arthritis, unspecified shoulder
M08.021	Unspecified juvenile rheumatoid arthritis, right elbow
M08.022	Unspecified juvenile rheumatoid arthritis, left elbow
M08.029	Unspecified juvenile rheumatoid arthritis, unspecified elbow
M08.031	Unspecified juvenile rheumatoid arthritis, right wrist
M08.032	Unspecified juvenile rheumatoid arthritis, left wrist

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CMS / Medicare notesmixed

No codes listed

HCPCS units per 30 days — threshold

Maximum HCPCS units per 30 days≤ 9250 billable units per 30 days

Measurement unitHCPCS billable units (1 unit = 1 mg for J9210)

Limiting periodPer 30-day period

Related prior authorization noteMaximum enforced at prior authorization and during claim adjudication

Medicare Part B Covered Diagnosis Codes

Medicare Part B covered diagnosis codes

Provider Actions, Authorization, and Documentation Requirements

Prior Authorization

Prior Authorization, Duration, Limits, and Billing Code

Prior authorization is required. Initial approval will be provided for 6 months and may be renewed every 6 months thereafter.

Max 9250 billable units per 30 days
HCPCS: J9210 - Injection, emapalumab-lzsg, 1 mg (1 billable unit = 1 mg)

Denial Risk

Infection and Vaccine Contraindications and Monitoring

Do not initiate therapy in patients with an active infection, including clinically important localized infections that are favored by interferon-gamma neutralization (for example, infections caused by mycobacteria or Histoplasma capsulatum). Patients must be screened for latent tuberculosis prior to treatment and monitored for TB during therapy. Providers should monitor and consider prophylaxis for Herpes Zoster, Pneumocystis jirovecii, and fungal infections. Emapalumab must not be administered concurrently with live or live-attenuated vaccines.

Background

Hemophagocytic lymphohistiocytosis (HLH) is a hyperinflammatory syndrome that may be primary (genetic) or secondary, including macrophage activation syndrome (MAS) associated with Still's disease. Emapalumab (Gamifant) is an anti–interferon-γ therapy indicated for primary HLH and has been studied in HLH/MAS contexts; understanding whether disease is primary versus secondary guides diagnostic requirements and prior-therapy expectations for coverage.

Definitions and Diagnostic Criteria

Primary HLH — diagnostic and treatment requirements

Definitive diagnostic optionIdentification of biallelic pathogenic gene variants on molecular genetic testing (e.g., PRF1, UNC13D, STX11, STXBP2) or family history consistent with primary HLH

Alternative diagnostic optionFulfillment of at least five of eight specified HLH criteria (fever >7 days; splenomegaly; cytopenias in ≥2 lineages; hypertriglyceridemia and/or hypofibrinogenemia; hemophagocytosis without malignancy; low/absent NK activity; ferritin ≥500 mcg/L; sCD25 ≥2400 U/mL)

Treatment status requirementPatient has active, primary disease refractory, recurrent, or progressive during conventional HLH therapy unless intolerant

Transplant exclusionPatient has NOT received hematopoietic stem cell transplant (HSCT)

HLH/MAS (Still's disease-associated) — diagnostic criteria

Ferritin threshold

Revision History

2019-01-03policy_effective

Policy effective date established.

2025-08-05last_reviewLatest

Policy last reviewed on this date; routine review documented.

2025-08-05next_review

Next scheduled review date set for this date.

OpenPayer

Gamifant (emapalumab-lzsg) (Intravenous)