In the phase 3 ASPEN-1 trial, 301 adults with moderate-to-severe cervical dystonia were randomized to receive a single treatment with daxibotulinumtoxinA for injection (DAXI) 125U, DAXI 250U, or placebo. Both DAXI doses significantly improved Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) total scores versus placebo at weeks 4 and 6, with treatment effects evident as early as week 2. Significant improvements were also observed across TWSTRS measures of severity, disability, and pain. Median duration of effect was 24.0 weeks with DAXI 125U and 20.3 weeks with DAXI 250U, and both clinician- and patient-rated responder rates were significantly higher with DAXI than placebo.

These findings suggest that DAXI may provide sustained symptom control and potentially extend the time between treatments for some patients. Most treatment-emergent adverse events were mild or moderate, and no treatment-related serious adverse events were reported. Treatment-related dysphagia occurred in 1.6% of patients receiving 125U and 3.8% receiving 250U, while muscular weakness occurred in 4.8% and 2.3%, respectively. Because ASPEN-1 evaluated only a single treatment cycle using fixed doses rather than individualized titration, additional longer-term data are needed to better define dosing strategies, durability of response, and outcomes over repeated treatment cycles.

Reference: Comella CL, Jankovic J, Hauser RA, et al. Efficacy and safety of daxibotulinumtoxinA for injection in cervical dystonia: ASPEN-1 phase 3 randomized controlled trial. Neurology. 2024 Feb 27;102(4):e208091. doi: 10.1212/WNL.0000000000208091.

Authors of a retrospective study evaluated the diagnostic and prognostic value of sural nerve biopsy in patients with suspected chronic inflammatory demyelinating polyneuropathy (CIDP) and other immune-mediated neuropathies. Among 163 patients who underwent biopsy, 73% had a diagnostically useful result: 51% showed histologic findings consistent with CIDP and 21% revealed other diagnoses, including vasculitis and microangiopathy. Patients selected for biopsy were less likely to have responded to immunotherapy than those who were not biopsied (36% vs 69%). Use of immunotherapy, including immunoglobulins and second-line agents, increased after biopsy. Importantly, routine clinical and laboratory measures, including disease duration, cerebrospinal fluid protein, nerve conduction findings, and disability scores, did not predict whether biopsy would provide useful diagnostic information.

For patients with suspected CIDP who are not responding as expected to treatment, the findings suggest that nerve biopsy may provide additional information when the diagnosis remains uncertain. Even among patients with no measurable sural sensory nerve action potential, 73% of biopsies yielded diagnostically useful findings, suggesting that severely affected nerves may still have histologic value. Histologic markers of disease progression were also associated with greater disability 1 year after biopsy, although this relationship was not maintained at 2 years. Because the study was retrospective and treatment response was assessed indirectly, the authors emphasize the need for additional prospective research. However, they conclude that sural nerve biopsy should be considered in selected patients with treatment-refractory suspected CIDP.

Reference: Klimas R, Kordes A, Huckemann S, et al. The multiple roles of nerve biopsy in the diagnosis and prognosis of suspected immune neuropathies. J Neurol. 2024 Aug;271(8):5109-5121. doi: 10.1007/s00415-024-12456-4.

Authors of a systematic review of 34 studies encompassing 3,720 pregnancies in women with myasthenia gravis (MG) found that symptom worsening was most likely during the first trimester and the first 6 months postpartum. Among 842 pregnancies with reported MG course, 30% experienced worsening during pregnancy, while 52% remained stable. In subset meta-analyses using consistent disease classifications, estimated worsening rates were 21% to 23%. Myasthenic crisis was uncommon, occurring in about 4% of pregnancies and 3% postpartum. Treatment patterns varied, with anti-acetylcholinesterase therapy used most often and corticosteroids, azathioprine, intravenous immunoglobulin, and plasmapheresis reported less frequently.

The findings highlight the importance of closer monitoring during the first trimester and postpartum period. Vaginal delivery was more common than cesarean delivery (68% vs 32%), and most cesarean sections were performed for obstetric rather than MG-related indications. Preterm birth occurred in 9% of pregnancies. Among 1,530 infants, 9% developed transient neonatal MG, supporting careful observation of newborns for myasthenic symptoms after delivery. Interpretation should remain cautious because the included studies were heterogeneous and generally had moderate-to-low methodological quality, underscoring the need for prospective studies to better guide pregnancy management in MG.

Reference: Miegel L, Hickstein J, Reibelt A, Heesen C, Schubert C. Myasthenia gravis and pregnancy: a systematic review and meta-analysis. J Neurol. 2026 Mar 5;273(3):184. doi: 10.1007/s00415-026-13724-1.