Polydefkis, Michael

Importance There is a lack of long-term efficacy and safety data on hereditary transthyretin amyloidosis with polyneuropathy (hATTR-PN) and on RNA interference (RNAi) therapeutics in general. This study presents the longest-term data to date on patisiran for hATTR-PN. Objective To present the long-term efficacy and safety of patisiran in adults with hATTR-PN. Design, Setting, and Participants This global open-label extension (OLE) of the APOLLO randomized clinical trial and phase 2 OLE study enrolled patients from 43 hospitals or clinical centers across 19 countries between July 2015 and August 2017, with follow-up until November 2022. Of 212 eligible patients with hATTR who completed the phase 3 APOLLO or phase 2 OLE parent studies, 211 enrolled in and 138 completed the global OLE. Intervention Patisiran, 0.3 mg/kg, intravenously once every 3 weeks for up to 5 years. Main Outcomes and Measures Outcomes evaluated at year 5 of the global OLE included disability (polyneuropathy disability [PND] score); polyneuropathy severity (Neuropathy Impairment Score [NIS]), nutritional status (modified body mass index [mBMI]), quality of life (Norfolk Quality of Life–Diabetic Neuropathy [Norfolk QOL-DN]), and Rasch-Built Overall Disability Scale (R-ODS), with no statistical hierarchy. Safety, survival probability, and mortality were also assessed. Results At the global OLE baseline, the mean (SD) age was 61.3 (12.3) years, and 156 patients (73.9%) were male. In 138 patients completing the study, PND scores remained stable or improved in 89 patients (65.0%), NISs showed a mean (SD) change of 10.9 (14.7), and mean (SD) mBMI (calculated as weight in kilograms divided by height in meters squared times serum albumin in grams per liter) increased by 46.4 (120.7) over 5 years from baseline. Norfolk QOL-DN and R-ODS scores showed mean (SD) changes of 4.1 (16.7) and –3.7 (6.2), respectively. Adverse events (AEs) leading to study withdrawal occurred in 47 patients (22.3%). Infusion-related reactions were the most common treatment-related AE (n = 34 [16.1%]). Overall, 41 patients (19.4%) died during the study. Patisiran treatment in the parent study and low familial amyloid polyneuropathy score at parent study baseline were associated with significantly improved survival. Conclusions and Relevance In the longest study of an RNAi therapeutic for any disease, patisiran treatment resulted in modest changes for patients with hATTR-PN with an acceptable safety profile. These results highlight the importance of initiating early treatment for hATTR and the potential of RNAi therapeutics in medicine. Trial Registration ClinicalTrials.gov Identifier: NCT02510261

INTRODUCTION: We examined autoimmunity markers (AIM) and autonomic dysfunction in patients with chronic neurogastroenterological symptoms and their relationship to joint hypermobility/hypermobility spectrum disorder (JH/HSD). METHODS: AIM positivity was defined as a diagnosis of known autoimmune/autoinflammatory disorder with at least 1 positive seromarker of autoimmunity or at least 2 positive seromarkers by themselves. Three cohorts were studied: (i) retrospective (n = 300), (ii) prospective validation cohort (n = 133), and (iii) treatment cohort (n = 40), administered open-label intravenous immunoglobulin (IVIG). RESULTS: AIM positivity was found in 40% and 29% of the retrospective and prospective cohorts, the majority of whom (71% and 69%, respectively) had autoinflammatory disorder. Significantly more patients with AIM had elevations of C-reactive protein (31% vs 15%, P < 0.001) along with an increased proportion of cardiovascular autonomic dysfunction (48% vs 29%; P < 0.001), small fiber neuropathy (20% vs 9%; P = 0.002), and HLADQ8 positivity (24% vs 13%, P = 0.01). Patients with JH/HSD were more likely to have AIM (43% vs 15%, P = 0.001) along with more severe autonomic and gastrointestinal (GI) symptom scores. IVIG treatment was associated with robust improvement in pain, GI, and autonomic symptoms, but adverse events were experienced by 62% of patients. DISCUSSION: Autoimmune markers and autonomic dysfunction are common in patients with unexplained GI symptoms, especially in those with JH/HSD. Many patients seem to respond to IVIG treatment, but this needs to be confirmed by controlled trials. These results highlight the need for vigilance for autoimmune and autonomic factors and JH/HSD in patients with neurogastroenterological disorders. Clinicaltrials.gov, NCT04859829.

Abstract Hereditary transthyretin (ATTRv; v for variant) amyloidosis is a rare, multisystem, progressive, and fatal disease in which polyneuropathy is a cardinal manifestation. Due to a lack of United States (US)‐specific guidance on ATTRv amyloidosis with polyneuropathy, a panel of US‐based expert clinicians convened to address identification, monitoring, and treatment of this disease. ATTRv amyloidosis with polyneuropathy should be suspected in unexplained progressive neuropathy, especially if associated with systemic symptoms or family history. The diagnosis is confirmed through genetic testing, biopsy, or cardiac technetium‐based scintigraphy. Treatment should be initiated as soon as possible after diagnosis, with gene‐silencing therapeutics recommended as a first‐line option. Consensus is lacking on what represents “disease progression” during treatment; however, the aggressive natural history of this disease should be considered when evaluating the effectiveness of any therapy.