Comparison of efficacy and tolerability of azathioprine, mycophenolate mofetil, and cyclophosphamide among patients with neuromyelitis optica spectrum disorder: A prospective cohort study

Comparison of efficacy and tolerability of azathioprine, mycophenolate mofetil, and lower dosages of rituximab among patients with neuromyelitis optica spectrum disorder

OBJECTIVE

To observe and compare the efficacy and tolerability of azathioprine (AZA), mycophenolate mofetil (MMF) and lower dosages of rituximab (RTX) among patients with neuromyelitis optica spectrum disorder.

METHODS

In this prospective cohort, AQP4-IgG-seropositive patients with neuromyelitis optica spectrum disorder (NMOSD) were enrolled and randomly divided into three groups, using AZA, MMF or lower dosages of RTX (defined as 100mg RTX intravenous injection, once per week for 4 consecutive weeks) respectively. Annualized relapse rate (ARR), EDSS scores, CD19+ B-cell counts in peripheral blood, serum AQP-4-IgG titre and drug adverse reactions were compared between three groups.

RESULTS

In the AZA group (n=22), MMF group (n=30) and RTX group (n=20), 54.5%, 60.0% and 65.0% of patients reached a relapse-free state and EDSS score improved in 90.9%, 83.3% and 90.0% of patients respectively. In addition, there was significant reduction in ARR in all the three groups. Reduced dosage of RTX exerted a significant effect in reducing CD19+ B-cell counts (P<0.01). Compared with the AZA group, the MMF group and the RTX group decreased the AQP-4-IgG titre evidently and caused fewer adverse events. Neither the Kaplan-Meier survival curves nor the Cox proportional hazard model indicated a significant difference in relapse among the three groups (P>0.05).

CONCLUSIONS

AZA, MMF and reduced dosages of rituximab are all effective in reducing ARR and improving the clinical symptom of patients with NMOSD. Lower dosages of RTX are more effective than the others in decreasing the CD19 B-cell counts. MMF and reduced RTX decrease AQP-4-IgG titre more and cause fewer adverse events than AZA. However, more multicentre studies are still needed to find more effective therapeutic regimen.

Paroxysmal Symptoms As the First Manifestation of Multiple Sclerosis Mimicking a Transient Ischemic Attack: A Report of Two Cases

Paroxysmal symptoms are unusual manifestations of multiple sclerosis (MS). When presented as the first clinical manifestation, paroxysmal symptoms may easily be mistaken for transient ischemic attack (TIA). Previously, several cases of MS that reported with paroxysmal symptoms were misdiagnosed as TIA. Here, we report two additional cases, focusing on the clinical characteristics of paroxysmal symptoms in MS. Both cases had paroxysmal symptoms as their first manifestation; one presented with transient dizziness, left face numbness, and right limb weakness, and the other presented with episodic lightheadedness, blurred vision, nausea, palpitations, and tremulousness upon standing. Both of the patients' symptoms were mistaken for TIA at first, based on microembolic signals recorded by transcranial Doppler, but were later correctly diagnosed with MS based on neuroimaging and lumbar puncture. The paroxysmal symptoms responded to carbamazepine and were relieved completely after administration of intravenous methylprednisolone and interferon. Herein, we aim to summarize the differences between paroxysmal symptoms seen in MS and TIA, to facilitate a timely differential diagnosis and recommend an early appropriate treatment.

Mutation of the cellular adhesion molecule NECL2 is associated with neuromyelitis optica spectrum disorder

AIMS

To investigate the association of the Nectin/Necl family genes with the risk of developing NMOSD.

METHODS

Whole-exome sequencing was performed on two familial NMOSD cases and two unaffected family members. Additionally, 106 patients with sporadic NMOSD and 212 healthy controls (HCs) underwent screening for mutant Necl2. Finally, the molecular weight and cellular localization of mutant NECL2 was examined in transfected HeLa cells.

RESULTS

We identified a novel deletion mutation in Necl2 (c.1052_1060delCCACCACCA; p. Thr351_Thr353del), which was associated with disease manifestation in the NMOSD familial cases. The frequency at which the mutation occurred in patients with sporadic NMOSD was significantly higher than for HCs (5.7% and 0, respectively; p<0.01). The mutation was located in the extracellular domain close to the transmembrane region, at a point in the protein sequence characterized by threonine enrichment. The mutant NECL2 had a lower molecular weight and exhibited defective trafficking to the cell surface.

CONCLUSIONS

Our results suggest that the Necl2 mutation identified herein may be associated with the risk of developing NMOSD. Furthermore, mutated NECL2 may play a role in the pathogenesis of the disease, potentially through its roles in axonal regeneration and/or via neuron-glia interactions that are relevant to myelination.

From Leflunomide to Teriflunomide: Drug Development and Immunosuppressive Oral Drugs in the Treatment of Multiple Sclerosis

BACKGROUND

Immunosuppressive drugs have been used in the treatment of multiple sclerosis (MS) for a long time. Today, orally available second generation immunosuppressive agents have been approved or are filed for licensing as MS therapeutics. Due to semi-selective targeting of cellular processes, these second-generation immunosuppressive compounds might rather be immunomodulatory. For example, Teriflunomide inhibits the de novo pyrimidine synthesis and thus only targets rapidly proliferating cells, including lymphocytes. It is used as first line disease modifying therapy (DMT) in relapsing-remitting MS (RRMS).

METHODS

Review of online content related to oral immunosuppressants in MS with an emphasis on Teriflunomide.

RESULTS

Teriflunomide and Cladribine are second-generation immunosuppressants that are efficient in the treatment of MS patients. For Teriflunomide, a daily dose of 14 mg reduces the annualized relapse rate (ARR) by more than 30% and disability progression by 30% compared to placebo. Cladribine reduces the ARR by about 50% compared to placebo but has not yet been licensed due to unresolved safety concerns. We also discuss the significance of older immunosuppressive compounds including Azathioprine, Mycophenolate mofetile, and Cyclophosphamide in current MS therapy.

CONCLUSION

Teriflunomide has shown a favorable safety and efficacy profile in RRMS and is a therapeutic option for a distinct group of adult patients with RRMS.