RARE DISEASE
NMDA receptor encephalitis
NMDA receptor encephalitis
NMDA receptor encephalitis
Synonyms: Limbic encephalitis with N-methyl-D-aspartate receptor antibodies, Limbic encephalitis with NMDA receptor antibodies, N-methyl-D-aspartate receptor encephalitis, NMDARE, anti-NMDA receptor encephalitis
Synonyms: Limbic encephalitis with N-methyl-D-aspartate receptor antibodies, Limbic encephalitis with NMDA receptor antibodies, N-methyl-D-aspartate receptor encephalitis, NMDARE, anti-NMDA receptor encephalitis
Synonyms: Limbic encephalitis with N-methyl-D-aspartate receptor antibodies, Limbic encephalitis with NMDA receptor antibodies, N-methyl-D-aspartate receptor encephalitis, NMDARE, anti-NMDA receptor encephalitis
Drug discovery
2
drugs
With orphan designations
Overview
Anti-NMDA receptor encephalitis is an autoimmune disorder mediated by IgG antibodies against the GluN1 subunit of NMDA receptors, causing synaptic dysfunction and neuropsychiatric symptoms (e.g., psychosis, seizures, dyskinesias, autonomic instability, and coma). Diagnosis requires CSF antibody testing, though MRI/EEG may support evaluation. Early immunotherapy (corticosteroids, IVIG, plasma exchange) and tumor resection (if present) improve outcomes, though recovery often spans months to years [1][4][8][17].
Population
Primarily affects young adults (median age 23–24 years) and children, with 4:1 female predominance [6][10].
Racial disparities: Higher incidence in Black (2.94/million/year), Hispanic (2.17), and Asian/Pacific Islander (2.02) vs. White individuals (0.40) [2][6].
Ovarian teratomas are identified in ~31% of cases, particularly in Black females (58%) [2][6][13].
Therapies
First-line: High-dose corticosteroids, IVIG, and plasmapheresis [3][5][17].
Second-line: Rituximab or cyclophosphamide for refractory cases [3][7][9].
Tumor-directed: Resection of ovarian teratomas improves prognosis [6][13].
- Maintenance immunosuppression (e.g., mycophenolate) is reserved for relapsing/severe cases [3][7].
Categories: rare neurological diseases
Research Papers
1,093 drug discovery papers related to NMDA receptor encephalitis, with 4 first-in-class and 7 next-in-class early-stage therapies forecasted to outperform the average preclinical success rate. Recent publications:
1,093 drug discovery papers related to NMDA receptor encephalitis, with 4 first-in-class and 7 next-in-class early-stage therapies forecasted to outperform the average preclinical success rate. Recent publications:
2026-07-10 | Anti-NMDA-receptor encephalitis and MOGAD associated optic neuritis: a case series
Introduction Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is a well-recognized autoimmune condition that often presents with neuropsychiatric symptoms and seizures. Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) often manifests as optic neuritis and, less frequently, as acute demyelinating encephalomyelitis or transverse myelitis. The co-occurrence of anti-NMDAR encephalitis and MOGAD is becoming increasingly recognized, but clinical series remain limited. Description of cases We present three patients with anti-NMDAR encephalitis and MOGAD optic neuritis (ON): two men, aged 19 and 26, and one woman, aged 36. Clinical presentations, signs, investigations, and management of each case are discussed. The 26-year-old man presented with altered mental status and concurrent vision loss. The 36-year-old woman presented with altered mental status during the encephalitis episode and developed vision loss 4 months after encephalitis. The 19-year-old man with a prior history of altered mental status, diagnosed with NMDA encephalitis 9 years earlier, presented with headache and vision loss. Abnormal T2/FLAIR lesions in the brain and/or spinal cord during the encephalitis episode and unilateral or bilateral optic nerve enhancement during the optic neuritis episode were detected on brain and orbital magnetic resonance imaging (MRI) in all patients. All patients tested positive for cerebrospinal fluid (CSF) anti-NMDAR antibodies during the encephalitis episode and had positive serum MOG titers during the optic neuritis episode. Each patient presented with bilateral, asymmetrically reduced visual acuity and diminished color vision. One patient exhibited bilateral temporal optic nerve pallor, while two patients had bilateral optic nerve edema. The diagnostic work-up revealed positive serum MOG titers (1:100, 1:10,000, and 1:10,000 in the 36/F, 26/M, and 19/M, respectively). The 36-year-old woman was treated with intravenous (IV) steroids, plasma exchange (PLEX), and rituximab during the encephalitis episode. During the optic neuritis episode, she was treated with IV steroids, IV immunoglobulin (IVIG), and rituximab, followed by long-term rituximab maintenance therapy. The 19-year-old man was treated for encephalitis with IV steroids, IVIG, and rituximab. During his optic neuritis episode, he received IV steroids, IVIG, and tocilizumab, followed by long-term tocilizumab maintenance therapy. The 26-year-old man was treated with IV steroids, PLEX, and rituximab during the acute episode, followed by long-term IVIG maintenance therapy. After achieving 2 years of stability that prompted the discontinuation of IVIG, the patient experienced a MOG-IgG-positive relapse 5 months later. This relapse was marked by a seizure-like episode and the appearance of new lesions on MRI. The acute symptoms resolved after treatment with intravenous steroids and IVIG. Subsequently, the patient was initiated on an indefinite maintenance IVIG regimen. Visual acuity in all patients improved to their baseline levels following treatment. Conclusion This series highlights the emerging overlap between anti-NMDAR encephalitis and MOGAD optic neuritis. Optic neuritis may occur months to years after encephalitis, underscoring the need for careful monitoring of patients with anti-NMDAR encephalitis who develop new visual symptoms. Dual autoimmunity may represent a distinct phenotype with implications for long-term immunotherapy.
2026-06-26 | Case Report: Ofatumumab for the treatment of refractory anti-NMDAR-positive autoimmune encephalitis.
This study reports three cases of refractory anti-NMDAR encephalitis patients who exhibited persistent severe neuropsychiatric symptoms after first-line immunotherapy (glucocorticoids, intravenous Immunoglobulin) and long-term (maintenance) immunotherapy (mycophenolate mofetil). These patients received subcutaneous injections of ofatumumab (OFA, 20 mg per dose), with dynamic monitoring of CD20+ B cell levels, antibody titers, imaging findings, and neurological function scores. All three patients showed significant improvement in psychiatric symptoms, cognitive function, and brain imaging after treatment, with CD20+ B cell levels rapidly declining to extremely low levels. Only one patient experienced mild bone pain and a low-grade fever, with no severe adverse events reported. Therefore, OFA provides a rapid, safe, and effective approach to alleviate symptoms in refractory anti-NMDAR encephalitis, offering a promising and well-tolerated therapeutic option for patients unresponsive to conventional treatments.
2026-06-23 | Functional and cognitive recovery after intensive care unit-initiated intensive rehabilitation in anti-N-methyl-D-aspartate receptor encephalitis: A long-term case report.
Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis is a severe autoimmune encephalitis that can result in prolonged coma, ventilator dependence, and long-term disability. Although immunotherapy is well established, the optimal timing and intensity of rehabilitation remain poorly defined. This report describes a rare case of adult anti-NMDAR encephalitis with profound neurological impairment who achieved remarkable functional and cognitive recovery following intensive, goal-oriented rehabilitation initiated while still in the intensive care unit (ICU). A 35-year-old woman with prior thyroid carcinoma and ovarian teratoma presented with fever, confusion, and behavioral changes progressing to decreased consciousness. She remained comatose for months despite extensive immunotherapy and supportive care. Anti-NMDAR encephalitis was confirmed by the detection of anti-NMDAR antibodies in both serum and cerebrospinal fluid. Neuroimaging excluded other causes of encephalopathy. The patient underwent sequential immunotherapy including high-dose corticosteroids, intravenous immunoglobulin, and plasma exchange, followed by rituximab, tocilizumab, and cyclophosphamide. After nearly 20 months of medical instability, she began intensive multidisciplinary rehabilitation-five sessions per week, 2 hours daily-while still in the ICU. Therapy targeted progressive mobilization, upper-limb activation, and communication training, delivered under continuous cardiorespiratory monitoring. Over 3 months, substantial improvement was observed: Modified Barthel Index increased from 0 to 72, Berg Balance Scale to 42, Mini-Mental State Examination to 9, and Manual Function Test to over 80 bilaterally. She achieved independent ambulation and daily self-care, with significant gains in language function. The patient reported high satisfaction with her regained independence and ability to resume normal activities, and no adverse events occurred during rehabilitation. This case demonstrates that active, structured rehabilitation can be safely implemented even in medically complex, prolonged cases of autoimmune encephalitis. Intensive, goal-directed therapy under ICU monitoring may promote late neuroplasticity and yield meaningful recovery long after disease onset. Rehabilitation should be considered an an integral therapeutic component alongside immunotherapy in the long-term management of severe anti-NMDAR encephalitis.
2026-07-10 | Anti-NMDA-receptor encephalitis and MOGAD associated optic neuritis: a case series
Introduction Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is a well-recognized autoimmune condition that often presents with neuropsychiatric symptoms and seizures. Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) often manifests as optic neuritis and, less frequently, as acute demyelinating encephalomyelitis or transverse myelitis. The co-occurrence of anti-NMDAR encephalitis and MOGAD is becoming increasingly recognized, but clinical series remain limited. Description of cases We present three patients with anti-NMDAR encephalitis and MOGAD optic neuritis (ON): two men, aged 19 and 26, and one woman, aged 36. Clinical presentations, signs, investigations, and management of each case are discussed. The 26-year-old man presented with altered mental status and concurrent vision loss. The 36-year-old woman presented with altered mental status during the encephalitis episode and developed vision loss 4 months after encephalitis. The 19-year-old man with a prior history of altered mental status, diagnosed with NMDA encephalitis 9 years earlier, presented with headache and vision loss. Abnormal T2/FLAIR lesions in the brain and/or spinal cord during the encephalitis episode and unilateral or bilateral optic nerve enhancement during the optic neuritis episode were detected on brain and orbital magnetic resonance imaging (MRI) in all patients. All patients tested positive for cerebrospinal fluid (CSF) anti-NMDAR antibodies during the encephalitis episode and had positive serum MOG titers during the optic neuritis episode. Each patient presented with bilateral, asymmetrically reduced visual acuity and diminished color vision. One patient exhibited bilateral temporal optic nerve pallor, while two patients had bilateral optic nerve edema. The diagnostic work-up revealed positive serum MOG titers (1:100, 1:10,000, and 1:10,000 in the 36/F, 26/M, and 19/M, respectively). The 36-year-old woman was treated with intravenous (IV) steroids, plasma exchange (PLEX), and rituximab during the encephalitis episode. During the optic neuritis episode, she was treated with IV steroids, IV immunoglobulin (IVIG), and rituximab, followed by long-term rituximab maintenance therapy. The 19-year-old man was treated for encephalitis with IV steroids, IVIG, and rituximab. During his optic neuritis episode, he received IV steroids, IVIG, and tocilizumab, followed by long-term tocilizumab maintenance therapy. The 26-year-old man was treated with IV steroids, PLEX, and rituximab during the acute episode, followed by long-term IVIG maintenance therapy. After achieving 2 years of stability that prompted the discontinuation of IVIG, the patient experienced a MOG-IgG-positive relapse 5 months later. This relapse was marked by a seizure-like episode and the appearance of new lesions on MRI. The acute symptoms resolved after treatment with intravenous steroids and IVIG. Subsequently, the patient was initiated on an indefinite maintenance IVIG regimen. Visual acuity in all patients improved to their baseline levels following treatment. Conclusion This series highlights the emerging overlap between anti-NMDAR encephalitis and MOGAD optic neuritis. Optic neuritis may occur months to years after encephalitis, underscoring the need for careful monitoring of patients with anti-NMDAR encephalitis who develop new visual symptoms. Dual autoimmunity may represent a distinct phenotype with implications for long-term immunotherapy.
2026-06-26 | Case Report: Ofatumumab for the treatment of refractory anti-NMDAR-positive autoimmune encephalitis.
This study reports three cases of refractory anti-NMDAR encephalitis patients who exhibited persistent severe neuropsychiatric symptoms after first-line immunotherapy (glucocorticoids, intravenous Immunoglobulin) and long-term (maintenance) immunotherapy (mycophenolate mofetil). These patients received subcutaneous injections of ofatumumab (OFA, 20 mg per dose), with dynamic monitoring of CD20+ B cell levels, antibody titers, imaging findings, and neurological function scores. All three patients showed significant improvement in psychiatric symptoms, cognitive function, and brain imaging after treatment, with CD20+ B cell levels rapidly declining to extremely low levels. Only one patient experienced mild bone pain and a low-grade fever, with no severe adverse events reported. Therefore, OFA provides a rapid, safe, and effective approach to alleviate symptoms in refractory anti-NMDAR encephalitis, offering a promising and well-tolerated therapeutic option for patients unresponsive to conventional treatments.
2026-06-23 | Functional and cognitive recovery after intensive care unit-initiated intensive rehabilitation in anti-N-methyl-D-aspartate receptor encephalitis: A long-term case report.
Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis is a severe autoimmune encephalitis that can result in prolonged coma, ventilator dependence, and long-term disability. Although immunotherapy is well established, the optimal timing and intensity of rehabilitation remain poorly defined. This report describes a rare case of adult anti-NMDAR encephalitis with profound neurological impairment who achieved remarkable functional and cognitive recovery following intensive, goal-oriented rehabilitation initiated while still in the intensive care unit (ICU). A 35-year-old woman with prior thyroid carcinoma and ovarian teratoma presented with fever, confusion, and behavioral changes progressing to decreased consciousness. She remained comatose for months despite extensive immunotherapy and supportive care. Anti-NMDAR encephalitis was confirmed by the detection of anti-NMDAR antibodies in both serum and cerebrospinal fluid. Neuroimaging excluded other causes of encephalopathy. The patient underwent sequential immunotherapy including high-dose corticosteroids, intravenous immunoglobulin, and plasma exchange, followed by rituximab, tocilizumab, and cyclophosphamide. After nearly 20 months of medical instability, she began intensive multidisciplinary rehabilitation-five sessions per week, 2 hours daily-while still in the ICU. Therapy targeted progressive mobilization, upper-limb activation, and communication training, delivered under continuous cardiorespiratory monitoring. Over 3 months, substantial improvement was observed: Modified Barthel Index increased from 0 to 72, Berg Balance Scale to 42, Mini-Mental State Examination to 9, and Manual Function Test to over 80 bilaterally. She achieved independent ambulation and daily self-care, with significant gains in language function. The patient reported high satisfaction with her regained independence and ability to resume normal activities, and no adverse events occurred during rehabilitation. This case demonstrates that active, structured rehabilitation can be safely implemented even in medically complex, prolonged cases of autoimmune encephalitis. Intensive, goal-directed therapy under ICU monitoring may promote late neuroplasticity and yield meaningful recovery long after disease onset. Rehabilitation should be considered an an integral therapeutic component alongside immunotherapy in the long-term management of severe anti-NMDAR encephalitis.
Access all drug discovery articles and probability of success in trials forecasts:
Access all drug discovery articles and probability of success in trials forecasts:
Drug Discovery Landscape
2 orphan drug designations for NMDA receptor encephalitis.
2 orphan drug designations for NMDA receptor encephalitis.
Drug | Therapy type | Regulator | Orphan designation | Approval | Sponsor |
|---|---|---|---|---|---|
Humanized one-armed monoclonal antibody | antibodies | FDA | 2022-12-29 | — | Arialys Therapeutics, Inc. |
satralizumab-mwge | antibodies | FDA | 2022-07-18 | — | Genentech, Inc. |
Let's accelerate rare disease drug discovery
Let's accelerate drug discovery
Get access to Explority AI's forecasts to outperform average preclinical success rates. Whether you're expanding your R&D pipeline, evaluating a partnership, or simply have a question — we'd love to hear from you.