Abstract Objective Interictal epileptiform spikes (IESs) are widely used biomarkers of epileptogenic tissue in presurgical epilepsy evaluation. However, their reliability for seizure onset zone (SOZ) localization in high‐density intracranial electroencephalography (iEEG) remains inconsistent. It is underexplored whether this variability reflects methodological differences across detection algorithms or a limitation of IESs as a biomarker. This study evaluates whether IES detection alone provides sufficient spatial specificity for accurate SOZ localization in iEEG. Methods We systematically benchmarked eight established IES detection algorithms using iEEG recordings from 35 patients with drug‐resistant focal epilepsy. To provide a clinically meaningful reference, algorithm performance was evaluated against the clinically defined SOZ. To refine detection outputs and move beyond only IES detection, we applied masking strategies to isolate informative IES subsets based on rate, amplitude, frequency, and co‐occurrence with high‐frequency oscillations (HFOs). Conceptually, masking acts as a spatial refinement strategy that progressively restricts diffuse IES activity to more focal, pathologically relevant event populations. Results Despite substantial variability in detection characteristics, SOZ localization performance (ratio of events originating from SOZ divided by total number of events) converged within a narrow range (.23–.51), suggesting that IESs exhibit an intrinsic ceiling in SOZ localization performance when used alone. Amplitude‐based masking yielded modest improvements, whereas frequency‐based masking reduced performance. In contrast, IES‐HFO co‐occurrence markedly improved localization, particularly when combined with rate‐based masking, achieving a median SOZ localization ratio of .89, exceeding IESs (.37) and HFOs (.63) evaluated independently. Significance These findings demonstrate that IES‐based SOZ localization may require moving beyond detection‐only approaches. The integration of informed, biomarker‐driven masking strategies provides a more robust framework for identifying the activity most relevant to the epileptogenic network and paves the way for future incorporation into the clinical decision‐making pipeline.
Five-Year Results With Patisiran for Hereditary Transthyretin Amyloidosis With Polyneuropathy
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