EVALUATING THE ECONOMIC VALUE OF MONOCLONAL ANTIBODIES FOR AQP4+ NMOSD IN THE US USING ATTACK-FREE SURVIVAL OVER A 5-YEAR HORIZON
Author(s)
Rosemarie Walch, MD1, Justin R. Abbatemarco, MD2, Moushmi Singh, MSc3, Therese Aubry de Maraumont, PharmD, MSc4, Kim Rand, PhD5, Martin Dalziel, PhD6, Dustin Cavida, PharmD4, ISTVAN M. MAJER, PhD7, Robert C. Sergott, MD8;
1Memorial Healthcare, Owosso, MI, USA, 2Mellen Center for Multiple Sclerosis Treatment and Research, Cleveland, OH, USA, 3Amgen, Uxbridge, United Kingdom, 4Amgen Inc., Thousand Oaks, CA, USA, 5Maths In Health, Klimmen, Netherlands, 6Oxford PharmaGenensis, Oxford, United Kingdom, 7Amgen Europe GmbH, Global HEOR, Rotkreuz, Switzerland, 8William H. Annesley, Jr., EyeBrain Center, Thomas Jefferson University, and Wills Eye Neuro-Ophthalmology, Philadelphia, PA, USA
1Memorial Healthcare, Owosso, MI, USA, 2Mellen Center for Multiple Sclerosis Treatment and Research, Cleveland, OH, USA, 3Amgen, Uxbridge, United Kingdom, 4Amgen Inc., Thousand Oaks, CA, USA, 5Maths In Health, Klimmen, Netherlands, 6Oxford PharmaGenensis, Oxford, United Kingdom, 7Amgen Europe GmbH, Global HEOR, Rotkreuz, Switzerland, 8William H. Annesley, Jr., EyeBrain Center, Thomas Jefferson University, and Wills Eye Neuro-Ophthalmology, Philadelphia, PA, USA
OBJECTIVES: Several monoclonal antibodies with different mechanisms, dosing schedules, and cost profiles are approved for the treatment of aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder (AQP4+ NMOSD). To inform clinical and payer decision making, we estimated the cost per additional attack-free life year for inebilizumab, satralizumab, and eculizumab compared with no maintenance relapse-prevention therapy (placebo).
METHODS: A systematic literature review identified three placebo-controlled randomized trials: N-MOmentum (inebilizumab), SAkuraStar (satralizumab), and PREVENT (eculizumab). Attack-free survival for inebilizumab versus placebo was extrapolated over a 5-year time horizon using time to first investigator-determined attack (TTFA) data from N-MOmentum. Investigator-determined attacks were used for analyses due to heterogeneity in adjudication criteria across trials and to better reflect routine clinical assessment. To adjust for differences in trial populations, attack-free survival for satralizumab and eculizumab was predicted by anchoring to inebilizumab, applying matching-adjusted indirect comparison hazard ratios (HRs) for inebilizumab vs satralizumab and inebilizumab vs eculizumab, leveraging individual patient data from N-MOmentum and published aggregate data from SAkuraStar and PREVENT. Five-year treatment costs were calculated using November 2025 wholesale acquisition cost drug prices. Sensitivity and scenario analyses evaluated robustness of results.
RESULTS: Five-year treatment costs for inebilizumab, satralizumab, and eculizumab were $1,542,734, $1,167,638, and $3,418,052, respectively. Estimated HRs for TTFA were 0.33 (95% CI 0.13−0.86) for inebilizumab vs satralizumab, and 1.00 (95% CI 0.35−2.87) for inebilizumab vs eculizumab. Corresponding incremental attack-free life years per patient over 5 years were similar for inebilizumab (3.2) and eculizumab (3.2), and lower for satralizumab (1.8). Cost per additional attack-free life year was lowest for inebilizumab ($487,927), followed by satralizumab ($646,756) and eculizumab ($1,079,916). Sensitivity and scenario analyses demonstrated results consistent with the primary analysis.
CONCLUSIONS: This comparative economic assessment provides payer-relevant evidence on the long-term value of monoclonal antibody therapies for AQP4+ NMOSD in the US and may help guide clinical and reimbursement decisions.
METHODS: A systematic literature review identified three placebo-controlled randomized trials: N-MOmentum (inebilizumab), SAkuraStar (satralizumab), and PREVENT (eculizumab). Attack-free survival for inebilizumab versus placebo was extrapolated over a 5-year time horizon using time to first investigator-determined attack (TTFA) data from N-MOmentum. Investigator-determined attacks were used for analyses due to heterogeneity in adjudication criteria across trials and to better reflect routine clinical assessment. To adjust for differences in trial populations, attack-free survival for satralizumab and eculizumab was predicted by anchoring to inebilizumab, applying matching-adjusted indirect comparison hazard ratios (HRs) for inebilizumab vs satralizumab and inebilizumab vs eculizumab, leveraging individual patient data from N-MOmentum and published aggregate data from SAkuraStar and PREVENT. Five-year treatment costs were calculated using November 2025 wholesale acquisition cost drug prices. Sensitivity and scenario analyses evaluated robustness of results.
RESULTS: Five-year treatment costs for inebilizumab, satralizumab, and eculizumab were $1,542,734, $1,167,638, and $3,418,052, respectively. Estimated HRs for TTFA were 0.33 (95% CI 0.13−0.86) for inebilizumab vs satralizumab, and 1.00 (95% CI 0.35−2.87) for inebilizumab vs eculizumab. Corresponding incremental attack-free life years per patient over 5 years were similar for inebilizumab (3.2) and eculizumab (3.2), and lower for satralizumab (1.8). Cost per additional attack-free life year was lowest for inebilizumab ($487,927), followed by satralizumab ($646,756) and eculizumab ($1,079,916). Sensitivity and scenario analyses demonstrated results consistent with the primary analysis.
CONCLUSIONS: This comparative economic assessment provides payer-relevant evidence on the long-term value of monoclonal antibody therapies for AQP4+ NMOSD in the US and may help guide clinical and reimbursement decisions.
Conference/Value in Health Info
2026-05, ISPOR 2026, Philadelphia, PA, USA
Value in Health, Volume 29, Issue S6
Code
EE489
Topic
Economic Evaluation
Disease
SDC: Rare & Orphan Diseases, SDC: Systemic Disorders/Conditions (Anesthesia, Auto-Immune Disorders (n.e.c.), Hematological Disorders (non-oncologic), Pain)