Abstract
Objectives
Myasthenia Gravis (MG) is a chronic neuromuscular autoimmune disease with fluctuating severity and variable combination of weakness in ocular, bulbar, limb and respiratory muscles. About 15 to 20% of MG patients may experience severe acute symptoms (crisis) with impaired breathing requiring mechanical ventilation. MG patients in crisis receive immunomodulatory treatments such as IV immunoglobulin (IVIg) or plasma exchange (PE) to stabilize disease activity. This study examined the cost associated with these therapeutic options in acute MG patients from public payer perspective.
Methods
Schedules, National Hospital Cost Data Collection and MSAC HTA assessment report. A cost minimization analysis was performed. The model was created on a Microsoft Excel spreadsheet using micro-costing approach. Data on treatment outcomes were found in published literature. The model assumed non-inferior efficacy, safety and morbidity for both therapies.
Results
In 2018, NBA BloodSTAR database recorded 201 MG crisis patients receiving IVIg treatment. Using the IVIg base cohort, we projected 20% (n=50) of MG crisis patients were treated with plasma exchange. The estimated overall cost of IVIg and PE treatment is AUD 75,318 and AUD 71,334 for each MG crisis episode, respectively. Failure to test for MuSK antibodies prior to initiation of IVIg treatment will cost an additional AUD 9,308 per positive patient.
Conclusions
The economic evaluation of these therapies showed that PE is less costly than IVIg. The estimated savings with cTPE may be underestimated due to a lack of local treatment outcome data.