Last Review Date: 09/04/2025

Date of Origin: 06/05/2025

Dates Reviewed: 06/2025, 09/2025

1. Length of Authorization

• Initial: Prior authorization validity will be provided initially for 6 months.
• Renewal: Prior authorization validity may be renewed every 12 months thereafter.

2. Dosing Limits

        Max Units (per dose and over time) [HCPCS Unit]:

• 1,200 billable units initially then 600 billable units every two weeks thereafter

3. Initial Approval Criteria

Target Agent(s) will be approved when ALL of the following are met:

• ONE of the following:
  • The patient has a diagnosis of generalized Myasthenia Gravis (gMG) AND ALL of the following:
    • ONE of the following: (medical records required)
      • The patient has a positive serological test for anti-AChR antibodies; OR
      • The patient has a positive serological test for anti-MuSK antibodies; AND
    • The patient has a Myasthenia Gravis Foundation of America (MGFA) clinical classification class of II-IVb; AND
    • The patient has a MG-Activities of Daily Living total score of greater than or equal to 6; AND
    • ONE of the following:
      • The patient’s current medications have been assessed and any medications known to exacerbate myasthenia gravis (e.g., beta blockers, procainamide, quinidine, magnesium, anti-programmed death receptor-1 monoclonal antibodies, hydroxychloroquine, aminoglycosides) have been discontinued; OR
      • Discontinuation of the offending agent is NOT clinically appropriate; AND
    • ONE of the following:
      • The patient has tried and had an inadequate response to at least ONE conventional agent used for the treatment of myasthenia gravis (i.e., corticosteroids, azathioprine, cyclosporine, mycophenolate mofetil, tacrolimus, methotrexate, cyclophosphamide); OR
      • The patient has an intolerance or hypersensitivity to ONE conventional agent used for the treatment of myasthenia gravis (i.e., corticosteroids, azathioprine, cyclosporine, mycophenolate mofetil, tacrolimus, methotrexate, cyclophosphamide); OR
      • The patient has an FDA labeled contraindication to ALL conventional agents used for the treatment of myasthenia gravis (i.e., corticosteroids, azathioprine, cyclosporine, mycophenolate mofetil, tacrolimus, methotrexate, cyclophosphamide); OR
      • The patient required chronic intravenous immunoglobulin (IVIG); OR
      • The patient required chronic plasmapheresis/plasma exchange; OR

• • The patient has another FDA labeled indication for the requested agent and route of administration; AND
• If the patient has an FDA labeled indication, then ONE of the following:
  • The patient’s age is within FDA labeling for the requested indication for the requested agent; OR
  • There is support for using the requested agent for the patient’s age for the requested indication; AND
• The prescriber is a specialist in the area of the patient’s diagnosis (e.g., neurologist), or the prescriber has consulted with a specialist in the area of the patient’s diagnosis; AND
• The patient will NOT be using the requested agent in combination with Soliris (eculizumab), Bkemv (eculizumab-aeeb), Epysqli (eculizumab-aagh), Ultomiris (ravulizumab-cwvz), Vyvgart (efgartigimod),Vyvgart Hytrulo (efgartigimod alfa and hyaluronidase-qvfc), Zilbrysq (zilucoplan), or Rystiggo (rozanolixizumab-noli); AND
• The patient does NOT have any FDA labeled contraindications to the requested agent; AND
• The requested quantity (dose) is within FDA labeled dosing for the requested indication

4. Renewal Criteria

Target Agent(s) will be approved when ALL of the following are met:

• The patient has been previously approved for the requested agent through the plan’s Medical Drug Review process (Note: patients not previously approved for the requested agent will require initial evaluation review); AND
• The patient has had clinical benefit with the requested agent; AND
• The prescriber is a specialist in the area of the patient’s diagnosis (e.g., neurologist), or the prescriber has consulted with a specialist in the area of the patient’s diagnosis; AND
• The patient will NOT be using the requested agent in combination with Soliris (eculizumab), Bkemv (eculizumab-aeeb), Epysqli (eculizumab-aagh), Ultomiris (ravulizumab-cwvz), Vyvgart (efgartigimod), Vyvgart Hytrulo (efgartigimod alfa and hyaluronidase-qvfc), Zilbrysq (zilucoplan), or Rystiggo (rozanolixizumab-noli); AND
• The patient does NOT have any FDA labeled contraindications to the requested agent; AND
• The requested quantity (dose) is within FDA labeled dosing for the requested indication

5. Dosage/Administration 

   Indication	Dose
   Generalized Myasthenia Gravis (gMG)	The recommended initial dosage of Imaavy is 30 mg/kg administered once via intravenous infusion over at least 30 minutes. Two weeks after the initial dosage administer a maintenance dosage of 15 mg/kg via intravenous infusion over at least 15 minutes. Continue the maintenance dosage every two weeks thereafter.

6. Billing Code/Availability Information

HCPCS Code:

• J3590 – Unclassified biologics
• C9305 – Injection, nipocalimab-aahu, 3 mg; 1 billable unit = 3 mg (Effective 10/01/2025)
• C9399 – Unclassified drugs or biologicals (Hospital Outpatient Use Only) (Discontinue use on 10/01/2025)

NDC(s):

• Imaavy 300 mg/1.62 mL solution in a single-dose vial: 57894-0800-xx
• Imaavy 1,200 mg/6.5 mL solution in a single-dose vial: 57894-0801-xx

7. References

1. Imaavy [package insert]. Horsham, PA; Janssen Biotech, Inc., April 2025. Accessed May 2025.
2. Sussman J, Farrugia ME, Maddison P, et al. Myasthenia gravis: Association of British Neurologists’ management guidelines. Pract Neurol 2015; 15: 199-206.
3. Narayanaswami P, Sanders D, Wolfe G, Benatar M, et al. International consensus guidance for management of myasthenia gravis, 2020 update. Neurology® 2021;96:114-122. doi:10.1212/WNL.0000000000011124.
4. Antozzi C, Vu PT, Ramchandren S, et al. Safety and efficacy of nipocalimab in adults with generalised myasthenia gravis (Vivacity-MG3): a phase 3, randomised, double-blind, placebo-controlled study. The Lancet Neurology, Volume 24, Issue 2, 105 - 116
5. Jayam-Trouth A, Dabi A, Solieman N, Kurukumbi M, Kalyanam J. Myasthenia gravis: a review. Autoimmune Dis. 2012;2012:874680. doi:10.1155/2012/874680
6. Bril V, Druzdz A, Grosskreutz J, et al. Long-term Efficacy and Safety of Symptom-driven Cyclic Rozanolixizumab Treatment in Patients with Generalized Myasthenia Gravis: A Pooled Analysis of a Phase 3 Study and Two Open-label Extension Studies (P1-5.012). Neurology Apr 2023, 100 (17 Supplement 2) 3747; DOI: 10.1212/WNL.0000000000203497
7. Guidon AC, Muppidi S, Nowak RJ,  et al. Telemedicine visits in myasthenia gravis: expert guidance and the Myasthenia Gravis Core Exam (MG-CE). Muscle Nerve 2021; 64:270-276
8. Gronseth GS, Barohn R, Narayanaswami P. Practice advisory: Thymectomy for myasthenia gravis (practice parameter update): Report of the Guideline Development, Dissemination, and Implementation Subcommittee of the American Academy of Neurology. Neurology. 2020;94(16):705. Epub 2020 Mar 25.

Appendix A – Non-Quantitative Treatment Limitations (NQTL) Factor Checklist

Non-quantitative treatment limitations (NQTLs) refer to the methods, guidelines, standards of evidence, or other conditions that can restrict how long or to what extent benefits are provided under a health plan. These may include things like utilization review or prior authorization. The utilization management NQTL applies comparably, and not more stringently, to mental health/substance use disorder (MH/SUD) Medical Benefit Prescription Drugs and medical/surgical (M/S) Medical Benefit Prescription Drugs. The table below lists the factors that were considered in designing and applying prior authorization to this drug/drug group, and a summary of the conclusions that Prime’s assessment led to for each.

Appendix 1 – Covered Diagnosis Codes

Appendix 2 – Centers for Medicare and Medicaid Services (CMS)

The preceding information is intended for non-Medicare coverage determinations. Medicare coverage for outpatient (Part B) drugs is outlined in the Medicare Benefit Policy Manual (Pub. 100-2), Chapter 15, §50 Drugs and Biologicals. In addition, National Coverage Determinations (NCDs) and/or Local Coverage Determinations (LCDs) may exist and compliance with these policies is required where applicable. Local Coverage Articles (LCAs) may also exist for claims payment purposes or to clarify benefit eligibility under Part B for drugs which may be self-administered. The following link may be used to search for NCD, LCD, or LCA documents: https://www.cms.gov/medicare-coverage-database/search.aspx. Additional indications, including any preceding information, may be applied at the discretion of the health plan.

Medicare Part B Covered Diagnosis Codes (applicable to existing NCD/LCD/LCA): N/A