Durability of the Rituximab Response in Acetylcholine Receptor Autoantibody-Positive Myasthenia Gravis

IMPORTANCE: Myasthenia gravis (MG), an autoimmune disorder of neuromuscular transmission, is treated by an array of immunotherapeutics, many of which are nonspecific. Even with current therapies, a subset of patients has medically refractory MG. The benefits of B-cell-targeted therapy with rituximab have been observed in MG; however, the duration of these benefits after treatment is unclear. OBJECTIVE: To evaluate the durability of response to rituximab in the treatment of acetylcholine receptor autoantibody-positive (AChR+) generalized MG. DESIGN, SETTING AND PARTICIPANTS: This retrospective case series study included 16 patients with AChR+ MG referred to an MG clinic from January 1, 2007, to December 31, 2015. The patients were treated with rituximab and followed up for 18 to 84 months after treatment. MAIN OUTCOMES AND MEASURES: Assessment of long-term clinical response, durability of response and/or relapse rate, AChR autoantibody levels, adverse effects, and inflammatory markers. RESULTS: In the 16 patients (6 men and 10 women; median age, 42 [range, 18-69] years), clinical improvement was observed in parallel with complete withdrawal or reduction of other immunotherapies, with all patients achieving complete stable remission, pharmacologic remission, or minimal manifestations based on the Myasthenia Gravis Foundation of America postintervention status criteria. Nine patients (56%) had a relapse during a mean follow-up of 36 (range, 24-47) months. Seven patients (44%) remained relapse free with a mean follow-up of 47 (range, 18-81) months since the last rituximab treatment. All values were normalized to a pretreatment anti-AChR antibody level of 100% and the mean levels after each rituximab cycle were calculated. A 33% decrease was seen after cycle 1 of rituximab treatment (100% vs 67%; P = .004); 20% after cycle 2 (compared with cycle 1) (67% vs 47%; P = .008); and 17% after cycle 3 (compared with cycle 2) (47% vs 30%; P = .02). However, the serum cytokine levels measured were found to be unchanged. CONCLUSIONS AND RELEVANCE: Rituximab therapy appears to be an effective option in patients with refractory AChR+ MG, who were observed to have a durable response after treatment. Identification of markers of disease relapse and sustained remission are critical next steps in the development of pathophysiology-relevant, evidence-based practice parameters for rituximab in the treatment of MG

Highly Visible Wall‐Timer to Reduce Endovascular Treatment Time for Stroke

Background Endovascular therapy for acute ischemic stroke has revolutionized clinical care for patients with stroke and large vessel occlusion, but treatment remains time sensitive. At our stroke center, up to half of the door‐to‐groin time is accounted for after the patient arrives in the angio‐suite. Here, we apply the concept of a highly visible timer in the angio‐suite to quantify the impact on endovascular treatment time. Methods This was a single‐center prospective pseudorandomized study conducted over a 32‐week period. Pseudorandomization was achieved by turning the timer on and off in 2‐week intervals. The primary outcome was angio‐suite‐to‐groin time, and secondary outcomes were angio‐suite‐to‐intubation time, groin‐to‐recanalization time, and 90‐day modified Rankin scale. A stratified analysis was performed based on type of anesthesia (ie, endotracheal intubation versus not). Results During the 32‐week study period, 97 mechanical thrombectomies were performed. The timer was on and off for 38 and 59 cases, respectively. The timer resulted in faster angio‐suite‐to‐groin time (28 versus 33 minutes; P=0.02). The 5‐minute reduction in angio‐suite‐to‐groin was maintained after adjusting for intubation status in a multivariate regression (P=0.02). There was no difference in the 90‐day modified Rankin scale between groups. The timer impact was consistent across the 32‐week study period. Conclusions A highly visible timer in the angio‐suite achieved a meaningful, albeit modest, reduction in endovascular treatment time for patients with stroke. Given the lack of risk and low cost, it is reasonable for stroke centers to consider a highly visible timer in the angio‐suite to improve treatment times