Citations

Background: Artificial intelligence (AI) is a promising tool to aid in diagnostic accuracy and patient communication. Prior literature has shown that ChatGPT answers medical questions and can accurately diagnose surgical conditions. The purpose of this study was to determine the accuracy of ChatGPT 4.0 in evaluating radiologic imaging of common orthopedic upper extremity bony pathologies, including identifying the imaging modality and diagnostic accuracy. Methods: Diagnostic imaging was sourced from an open-source radiology database for 6 common upper extremity bony pathologies: distal radius fracture (DRF), metacarpal fracture (MFX), carpometacarpal osteoarthritis (CMC), humerus fracture (HFX), scaphoid fracture (SFX), and scaphoid nonunion (SN). X-ray, computed tomography (CT), and magnetic resonance imaging (MRI) modalities were included. Fifty images were randomly selected from each pathology where possible. Images were uploaded to ChatGPT 4.0 and queried for imaging modality, laterality, and diagnosis. Each image query was completed in a new ChatGPT search tab. Multinomial linear regression was used to identify variations in ChatGPT’s diagnostic accuracy across imaging modalities and medical conditions. Results: Overall, ChatGPT provided a diagnosis for 52% of images, with accuracy ranging from 0% to 55%. Diagnostic accuracy was significantly lower for SFX and MFX relative to HFX. ChatGPT was significantly less likely to provide a diagnosis for MRI relative to CT. Diagnostic accuracy ranged from 0% to 40% with regard to imaging modality (x-ray, CT, MRI) though this difference was not statistically significant. Conclusions: ChatGPT’s accuracy varied significantly between conditions and imaging modalities, though its iterative learning capabilities suggest potential for future diagnostic utility within hand surgery.

Background/Objectives: Spino-plastic surgery describes a specialized, multidisciplinary approach to addressing various spinal pathologies. The field is the innovative product of a multidisciplinary collaboration between plastic and reconstructive, orthopedic, and neurosurgery. Over the last few decades, this collaboration has borne promising surgical techniques and treatment plans geared toward restoring form, function, and aesthetics in patients with a variety of spinal conditions, including failed fusions, pseudoarthrosis, and the need for oncologic reconstruction. This paper explores the application of spino-plastic surgery in the context of post-sarcoma resection reconstructions, focusing on the efficacy in addressing the unique challenges posed by extensive tissue loss and structural deformities. Methods: Our study reviews a series of cases wherein spino-plastic techniques were utilized in patients with sarcomas of the spine and adjacent structures. We also discuss the technical considerations, including preoperative planning, intraoperative challenges, and overall patient care, that are crucial for the success of spino-plastic procedures. Results: The outcomes demonstrate significant improvements in patient mobility, pain reduction, and overall quality of life. Most notably, spino-plastic surgical techniques help facilitate the restoration of functional anatomy by leveraging vascularized bone grafts and muscle flaps, thereby enhancing long-term stability and reducing the risk of complications such as nonunion or infection. Conclusions: Spino-plastic collaboration represents a pivotal advancement in oncologic treatment, spinal care, and reconstructive surgery, offering new hope for patients undergoing post-sarcoma reconstruction. Further research and refinement of the techniques will only expand their application and improve outcomes for a broader range of patients in the future.

ABSTRACT Background Tricuspid valve‐in‐valve (TVIV) implantation has traditionally included post‐procedure overnight in‐hospital observation with next‐day discharge. Recently, our practice has shifted toward same‐day discharge for most patients after vascular access site hemostasis and adequate recovery from anesthesia. However, data on the safety of this approach remains scarce. Aims Our study aims to describe our practice change and to identify factors that may lead to overnight observation post‐TVIV. Methods We retrospectively reviewed medical records of patients who underwent uncomplicated TVIV implantation as an outpatient procedure at Mayo Clinic between 2011 and 2023. Results Of the 83 patients who underwent TVIV from 2011 to 2023, 65 (78%) were included in the study. The first 39 patients in our institutional series were observed overnight as standard practice. 18 (69%) of the most recent 26 patients in our series were discharged the same day; three patients who remained in the hospital overnight were because of provider preference and/or patient preference without any specific medical concern. Of all 47 patients who were observed overnight, one patient was treated for fluid overload, one patient had non‐sustained ventricular tachycardia on telemetry that resulted in adjustment of antiarrhythmic therapy, two patients had continued bleeding from the access sites and was observed for another day. Among the two of them, one also developed atrial tachyarrhythmias requiring initiation of additional antiarrhythmic therapy. Out of 18 patients discharged the same day, one patient had an ED presentation within 24 h due to access site bleeding which was resolved promptly. There was no mortality or procedural‐related readmission. Conclusion Same‐day discharge may be considered for adult patients who have undergone uncomplicated TVIV with adequate hemostasis and recovery after anesthesia.

Background: The BeatAML Master Trial (BAMT) began in 2016 with a goal of determining the feasibility of a precision-medicine approach in treating acute myeloid leukemia (AML) in older adults ≥ 60 years of age where outcomes are poor. At the time, standard of care (SOC) for older patients with AML was intensive 7+3 chemotherapy (cytarabine + daunorubicin) if fit and hypomethylating agents (HMA: azacitidine or decitabine) if unfit. Besides confirming the feasibility, the early results (2019) from the Master Trial suggested that patients who received therapy on one of the sub-studies had a lower early death rate and superior overall survival compared to patients receiving off-protocol SOC, which was primarily single-agent HMA at the time. Since then, the 2019 approval of venetoclax (ven) + azacitidine for older unfit AML patients has been transformative and emerged as the SOC. Using data from the BAMT from 2016-2024, we suggest that knowing the comprehensive genomic profile of AML at the time of diagnosis is still beneficial in determining therapy that would lead to the optimal outcome and that development of targeted therapies and combination regimens with ven/HMA is still needed. Methods: This is a retrospective analysis of 1096 patients who consented and enrolled on the BAMT (NCT03013998) from Nov 2016 through Jun 2024. Patients ≥ 60 years with newly diagnosed AML were included. Patients underwent therapy on a BeatAML sub-study based on their genetics (N=433) or treatment off-protocol (N=663). We divided the patients according to what therapy they received: (1) Non-Intensive (Off-Protocol, N=121), (2) Ven/HMA (Off-Protocol, N=234), (3) Non-Intensive (Sub-Study, N=407), (4) Intensive (Sub-Study, N=26), and (5) Intensive (Off-Protocol, N=155). 94 patients received no treatment and 59 were unknown. Non-intensive therapies included primarily targeted agents or non-ven combinations. We analyzed baseline characteristics and demographics, overall survival (OS), and the impact of allogenic stem cell transplant (SCT). OS, using Kaplan-Meier method, was measured from the start of therapy to all-cause death, censoring patients at last follow-up. Results: Characteristics and demographics were similar between Groups 1, 2 and 3. Group 4 and 5 were treated with intensive chemotherapy and their characteristics are reflective of younger/fit patients appropriate for the intensive regimen. Groups 4 and 5 also had the longest median OS (mOS) of 40.2 months (95% CI: 13.9-not reached (NR)) and 42.3 months (95% CI: 25.1-NR) respectively. Group 3, which included patients treated with a non-intensive, targeted therapy on a sub-study, had an mOS of 14.0 months (95% CI: 12.3-16.7), which was similar to Group 2, treated with Ven/HMA, that had an mOS of 13.2 months (95% CI: 10.9-16.3). Lastly, patients in Group 1, who were treated primarily with HMA monotherapy, did poorly in comparison, with an mOS of 6.0 months (95% CI: 3.3-10.1). Additionally, we looked at the cumulative incidence rate (CIR) of SCT. The CIR in 12 months of Group 1 was 9.8% (95% CI: 6.9-13.4), Group 2: 5.4% (95% CI: 2.2-10.7), Group 3 and 4 combined: 35.0% (95% CI: 628.1-42.1), and Group 5: 13.1% (95% CI: 6.9-13.4). In a multi-variable analysis, after adjusting for typical favorable risk factors like NPM1 mutations and core binding factor, SCT was highly significant (p<0.0001) in improving OS with a hazard ratio of 0.23 (95% CI: 0.16-0.32), and Group 3 performed similarly to Group 2 (p=0.20). Conclusions: First, our results suggest that it is clinically relevant to correctly identify whether an intensive chemotherapy, targeted-therapy, or ven/HMA regimen is best suited for older AML patients, for which a precision-medicine trial is ideal for. Secondly, in this group of patients, our results show that patients treated with a non-intensive targeted therapy (Group 3) has a similar mOS to those treated with ven/HMA (Group 2). Especially after controlling for patient characteristics, patients in Group 2 performed similar to those in Group 3 (p=0.20). Patients in Group 3 were treated on Beat AML sub-studies which included targeted therapy alone or with non-venetoclax combinations, which is a strong rationale for continued development of targeted agents to optimize toxicity and quality of life with similar survival. Lastly, this data also supports the need to improve the ven/HMA SOC by developing combination regimens with targeted agents to further improve outcomes.

Background: Mutations of isocitrate dehydrogenase (IDH) are recurrent in acute myeloid leukemia (AML) and the prevalence increases with age. The prognostic impact of IDH1 and IDH2 mutations remains controversial. IDH inhibitors are small molecules that bind within the IDH enzymatic active site, blocking aberrant 2-hydroxyglutarate production and inducing myeloid differentiation. While they can lead to differentiation syndrome, they generally have a more favorable side-effect profile, making them an attractive option for older patients. We aimed to describe the prevalence and prognostic impact of IDH mutations in newly diagnosed (ND) AML patients ≥ 60 years in a large cohort of patients treated on a Leukemia and Lymphoma Society-sponsored trial. Methods: We performed a retrospective observational analysis including patients ≥ 60 years with ND AML who were enrolled on the Beat AML clinical trial (NCT03013998) before May 10, 2023. Patients were treated with a variety of treatment regimens. Cytogenetic analysis and next-generation sequencing (FoundationOne®Heme) were obtained. Mutations were considered present at any detectable VAF. Cox proportional hazard models were used to describe the relative risk of each variable on death over time from the date of trial inclusion. Results: A total of 1023 patients with ND AML were identified. Patients had a median age of 72 (range 60-92) years and the majority were non-Hispanic White (83.2%), and male (57.6%). Ninety-nine (9.7%) patients were IDH1MUT, 193 (18.9%) patients were IDH2MUT including 10 (1.0%) patients with a co-occurring IDH1 and IDH2 gene mutations. Both IDH1MUT and IDH2MUT were associated with 2022 ELN favorable-risk (26.3% and 22.3% for IDH1 and IDH2 respectively, vs 15.5% overall (P<0.001)). IDH1MUT significantly co-occurred with DNMT3AMUT (42.4%), NPM1MUT (44.4%) and less frequently with TP53MUT (10.1%) (P<0.001 for all). IDH2MUT was associated with DNMT3AMUT (35.8%), NPM1MUT (31.1%), SRSF2MUT (38.3%), and less frequently with TET2MUT (6.7%) and TP53MUT (9.3%) (P<0.001 for all). Normal karyotype was higher in IDH1MUT (P<0.001) and IDH2MUT (P<0.001), whereas complex karyotype (P<0.001 for both) and core-binding factor AML (P=0.047, P=0.015) were lower in IDH1MUT and IDH2MUT. To evaluate the impact of IDH mutations in patients ≥ 60 years, we focused on patients evaluable for outcome treated with lower-intensity therapy (LIT) (N=674), and intensive chemotherapy (IC) (N=178), separately. Among the LIT treated patients, 96 patients received treatment with an IDH inhibitor, and 237 patients received a hypomethylating agent (HMA) plus venetoclax. For patients treated with LIT, the hazard ratios (HRs) of death over time were 0.58 [95% CI 0.47-0.72; P<0.002], 0.81 [95% CI 0.59-1.13; P=0.214] and 0.56 [95% CI 0.44-0.72; P<0.001] for IDHMUT, IDH1MUT, IDH2MUT respectively. Among patients receiving IC, the HRs were 1.05 [95% CI 0.68-1.69; P=0.777], 0.70 [95% CI 0.31-1.61; P=0.406] and 1.27 [95% CI 0.77-2.1; P=0.352] for IDHMUT, IDH1MUT, and IDH2MUT respectively. The HR of death for IDH1MUT patients treated with LIT with the addition of an IDH1 inhibitor (N=24) was significantly lower (HR 0.47 [95% CI 0.24-0.92; P=0.027] vs IDH1MUT patients treated without an IDH1 inhibitor, while an IDH2 inhibitor did not change survivial outcomes in patients with IDH2MUT (N=71). Discussion: To our knowledge this is the largest retrospective study characterizing the prevalence of IDH mutations in patients ≥ 60 years with AML. We demonstrated that IDH mutations were detected in ~27% of older patients with AML. Although there could have been selection bias as the Beat AML study had separate IDHMUT study arms, these findings are concordant with other studies showing an increase in frequency of IDH mutations with age. IDH2MUT was associated with a lower HR of death among patients treated with LIT, which was not seen in patients receiving IC. The high prevalence of IDH mutations suggests that IDH inhibitors used as single agents or in combination with lower-intensity therapies are an important class of drugs for this older patient population as they are generally well tolerated, that need further investigation.

Autologous stem cell transplantation (ASCT) in AL amyloidosis effectively produces a high overall hematological response rate, complete response rate, and durable remissions. However, it is a high-dose chemotherapy-based therapy with high morbidity which can be offered only to a subset of AL amyloidosis patients who are considered fit for this therapy. Transplant-related mortality (TRM) in AL amyloidosis has decreased over the past three decades due to improvement in patient selection. New therapeutic options question the utilization of ASCT. A model to predict TRM can improve the decision-making process, patient selection and further reduce TRM. AL amyloidosis patients (n=1718) from 9 centers globally, transplanted in the years 2003-2020 were included. Pre-ASCT variables of interest were assessed for association with Day-100 all-cause mortality, including age at ASCT (≥ 60 years), sex, light chain isotype, ECOG performance status (ECOG PS; 0, 1 and 2/3), the difference between involved and uninvolved light chains (dFLC; ≥180 mg/L), N-terminal prohormone of B natriuretic peptide (NT-proBNP; ≥1800 pg/mL) or B-type natriuretic peptide (BNP; ≥400 pg/mL), left ventricle ejection fraction (LVEF, <50%), interventricular septum (>16 mm), corrected diffusing capacity for carbon monoxide (cDLCO; ≤65% of predicted), forced expiratory volume in one second (FEV1; ≤65% of predicted), serum albumin (<2.5 g/dL), estimated glomerular filtration rate (eGFR; <30 mL/min/m2), alkaline phosphatase (>X2 upper limit of normal), and systolic blood pressure (<100 mmHg). Troponins could not be included in our modeling given the multitude of assays used across institutions and periods that could not be reconciled. A random forest (RF) classifier with 10-fold cross-validation was used to assist in variable selection. The final model variables were selected based on statistical performance and clinical relevance. The model was fitted using logistic regression. The median age at ASCT was 58, and 40% of patients were women. The most frequently involved organs were the kidneys (69%) and the heart (52%). Mayo 2004 stages I and II were collectively present in 83% of patients. Day-100 TRM occurred in 75 patients (4.4%) with the 3 main causes being shock (n=27), cardiac arrhythmia (n=26), and organ failure (n=22). Age at ASCT, sex, and light chain isotype were not predictors of Day-100 TRM. Across the other pre-ASCT variables, adverse features were present from 6.9% (LVEF <50%) to 25.8% (dFLC ≥180 mg/L) of patients. Ten factors were associated with Day-100 TRM on univariate analysis. The odds ratio of these variables ranged from 1.6 to 10.2. RF classifier using all these variables identified a model with an area under the curve (AUC) of 0.72±0.12. Using the importance hierarchy function to refine the model selection, a 4-variable model [NT-proBNP/BNP ≥1800/400 pg/mL, serum albumin <2.5 g/dL, ECOG PS 1 or 2/3, and systolic blood pressure <100 mmHg] was built with an AUC of 0.70±0.12. Based on logistic regression coefficients, ECOG PS 2/3 was assigned two points, while other adverse predictors were assigned 1-point each (model score range 0-5). We then applied the model scoring to our study population. Score distribution was as follows: 0 (n=431, 25.1% of patients), 1 (n=688,40.1%), 2 (n=413, 24.0%), and 3 and above (n=186, 10.8%). Day-100 TRM rates were 0.46%, 3.2%, 5.8%, and 14.5% for 0, 1, 2, and ≥3 points, respectively. The respective rates for the years 2003-2011 were 1.1%, 3.3%, 6.4%, and 19.2%, while for the years 2012-2020 0%, 3.1%, 5.2%, and 8.4%. We developed a simple clinical tool to predict the Day-100 TRM risk in AL patients undergoing ASCT. This tool will allow more informed decision making weighing the individual benefits and risks of ASCT compared to other therapies.

Introduction Chimeric antigen receptor T-cell therapy (CART) has revolutionized the treatment algorithm of relapsed/refractory (R/R) B-cell non-Hodgkin lymphoma (NHL). However, approximately only 40% of cases achieve long-term durable remissions. Prognostication remains important as it would allow more precise prediction of outcomes and develop a personalized treatment approach. Currently, it is unclear whether prognostic factors that have been predictive of outcomes in the pre-CART era, remain important in the current era. We conducted a single center observational study to assess the prognostic significance of extra nodal involvement (ENI) on long-term outcomes following CART in B-cell NHL. Methods The primary aim was to evaluate the prognostic significance of ENI on long-term outcomes in patients with B-cell NHL treated with CART. The second aim was to specifically evaluate the impact of gastrointestinal (GI) involvement. Continuous variables were summarized as median (range) and categorical variables were reported as frequency (percentage). Kaplan-Meier method was used to estimate freedom from events at different time points and draw corresponding survival curves. Log-rank test was used to compare freedom from events between histology groups. Results 74 patients were included in this analysis, with a median age of 62 (18-85) years. Fifty-three (72%) had evidence of ENI. Twenty-four (47%) had GI involvement as the sole site of ENI or with other sites of ENI. Forty-three (58%) patients were male and diffuse large B-cell lymphoma (DLBCL) was the most common histology (n=50 [54%]) followed by transformed follicular lymphoma (n=20 [27%]). Most patients had advanced stage disease at time of CART (n=71 [96%]) and 3 (4%) had CNS involvement at any time prior to CART. Median number of prior lines of systemic treatment were 2 (1-7) and 64 (87%) had progressive disease at time of CART. Axicabtagene ciloleucel was the most used CART product (n=68 [92%]); Grade 3-4 cytokine release syndrome was reported in 6 (8%) patients and grade 3-4 immune effector cell associated neurotoxicity syndrome was reported in 13 (18%) patients. ICU level of care was needed in 22 (30%) patients and 2 patients (3%) developed hemophagocytic lymphohistiocytosis-like syndrome. Sixty patients (87%) achieved an objective response and 34(49%) achieved a complete response. The 1-year OS was 66% (53-81) in patients who had ENI vs. 72% (54-97) in those without ENI (p=0.82); 1-year relapse rates were at 39% (20-54) vs. 36% (10-54) (p=0.95) for patients with ENI vs. those without ENI. No difference was noted between the two groups regarding progression-free survival and non-relapse mortality (NRM). No difference in outcomes was observed when patients who had GI involvement as the only site of ENI or in combination with other sites of ENI were compared to those who did not have GI involvement as one of the sites of ENI. Elevated LDH at the time of CART (HR 2.27 [95% CI 1.05-4.94], p=0.03), development of any grade ICANS (HR 2.77 [95% CI 1.27-6.04], p=0.01) and requirement for ICU level of care (HR 3.25 [95% CI 1.54-6.86], p=0.002) adversely affected OS; the impact of elevated LDH on OS remained significant in multivariate models (HR 2.34 [95% CI 1.05-5.27], p=0.04). Development of any grade CRS was associated with a decreased risk of relapse (HR 0.25 [95% CI 0.11-0.56], p=<0.001) and the requirement of ICU stay adversely affected NRM (HR 2.27 [95% CI 1.05-4.94], p=0.032). Conclusion These results suggest that ENI does not appear to be predictive of long-term outcomes in the setting of CART therapy. Patients who had ENI appeared to derive equal benefit from CART therapy. GI involvement as a site of ENI has been known to be associated with worse survival when compared to other sites of ENI but we did not observe any difference in this subgroup also. Evolving predictive models and/or biomarkers that take in account the dynamics of the interaction between the malignant and CART cells might help better inform prognostication in the current era.

Introduction: Light-chain amyloidosis (ALA) is a rare plasma cell disorder characterized by multiorgan involvement. Patients often present with non-specific symptoms, which can lead to a delay in diagnosis. This is associated with progressive organ involvement and shorter survival. Reducing the time from symptom onset to diagnosis is a critical step in improving outcomes. This study was designed to evaluate the clinical prodrome and challenges associated with the diagnosis of ALA from the patient perspective. Methods: This retrospective study surveyed patients with ALA through the online HealthTree® Cure Hub platform, which helps patients navigate their disease in a holistic way. The survey consisted of 32 questions, including 23 multiple-choice, 7 date-entry, and two free-response questions. Data on diagnosis and demographics were extracted from the electronic health record and self-reported data linked to HealthTree® Cure Hub. Results were reported as numbers and percentages, and comparisons were made by age (≥70 vs. <70 years) and sex. The following statistical methods were used: Fisher's exact test for categorical data, two-sample t-test and F-test for normally distributed continuous data, Wilcoxon rank-sum test for skewed data and Spearman correlation coefficient. Results: We surveyed 248 patients. Of those, a total of 87 patients with a self-reported diagnosis of ALA completed the questionnaire between March 12, 2023, and May 8, 2024. The median age was 66 years; 55% were female, and 91% were white. The most common initial symptoms prompting patients to seek medical evaluation were fatigue/weakness (47%), swelling (38%), shortness of breath (28%), chest pain (23%), and foamy urine (22%). Pain in hands/feet, carpal tunnel syndrome, loss of appetite, hoarseness, macroglossia, diarrhea, periorbital puffiness, nail changes, and erectile dysfunction each accounted for <10% of cases. Signs and symptoms were first detected by patients themselves in 58% of cases, by a physician in 33% and by a family member or friend for the rest. The median number of symptoms per individual was 2; 31% reported only one symptom, 37% 2-3, 18% 4-6, and 14% >6; with chest pain being the most common (39%), followed by swelling (22%), shortness of breath (13%), and foamy urine (13%); one patient reported erectile dysfunction and another reported arrhythmias as their only symptom. There was a correlation between hoarseness and nail changes (ρ=0.71), and carpal tunnel syndrome and orthostatic hypotension (ρ=0.63). Only 16% were aware of ALA as a condition prior to symptom onset. Thirty six percent presented to a general practitioner for initial evaluation; about 50% sought a specialist, including a myeloma/amyloid specialist (21%), and 14% were first evaluated in the emergency department. While most patients (45%) were diagnosed by a hematologist/oncologist, patients reported seeing a median of 3 physicians (range: 1-10) before the diagnosis was established. Among responders, 61% reported having myeloma at the time of testing. After diagnosis, about 50% were referred to a center specialized in ALA, and 72% met with a stem cell transplant specialist. Most patients reported receiving multidisciplinary care, with a median of 3 additional specialists participating in ALA care (range: 0-16). More than half of patients (59%) felt the diagnosis was delayed; among those, 42%, 24%, 24%, and 11% reported a delay of 1-6, 7-12, 13-24, and >24 months, respectively. The proportion of patients reporting >12-month delay was higher among older patients (54% vs. 27%, P=0.02). A quarter of responders felt their treatment was delayed. Half of patients felt the diagnostic delay contributed to a decrease in treatment efficacy and 48% did not feel that all medical professionals were knowledgeable about ALA. Only 38% felt the diagnostic process was simple and easy within their healthcare system. Conclusion: Most patients with AL amyloidosis initially present with non-specific symptoms, with fatigue/weakness being the most common. Over a third were evaluated first by a general practitioner, and about a third reported a diagnostic delay of >12 months. The diagnostic process is associated with high healthcare utilization, even among patients with concurrent multiple myeloma. Increasing disease awareness among patients and medical providers may shorten the time to diagnosis and contribute to improved outcomes.

Background Paroxysmal nocturnal hemoglobinuria (PNH) is a rare hematological disorder characterized by uncontrolled terminal complement activation. Treatment with terminal complement inhibitors ravulizumab or eculizumab has led to improved clinical outcomes for patients with PNH. Evidence on real-world treatment patterns and healthcare resource utilization (HRU) in this patient population, which includes emerging data on pegcetacoplan, is limited. Objective To describe real-world drug adherence and persistence in patients with PNH receiving ravulizumab, eculizumab or pegcetacoplan, and compare HRU for patients pre- and post-ravulizumab initiation in the USA. Methods ADVANTAGE is a retrospective, longitudinal analysis using the Komodo Health Research Database, a large multi-payer US health insurance claims dataset, among patients with PNH and ≥ 1 claim for ravulizumab, eculizumab or pegcetacoplan. Patients aged ≥ 18 years at index date (defined as the date of first claim for a given complement inhibitor on/after 1 January, 2019), with ≥ 12 months enrollment prior to this date, ≥ 1 claim with an ICD-10-CM code indicating PNH prior to/at index date and no ICD-10-CM code suggesting an alternative indication, were included. Patients were followed until the end of continuous enrollment, death, or end of data availability. Adherence was assessed by proportion of days covered (PDC) and treatment duration was estimated using Kaplan-Meier analysis. The HRU analysis included patients with ≥ 12 months follow-up and compared rates of HRU per-patient per-year (PPPY) in the 12 months pre- and post-ravulizumab treatment initiation. Pre-post differences in HRU were estimated using generalized estimating equations with robust standard errors. Results The sample included 344, 342 and 97 patients with index treatments for ravulizumab, eculizumab or pegcetacoplan, respectively. Age and sex distribution of patients were similar among patients treated with ravulizumab (mean age: 44 years; 57% female), eculizumab (mean age: 44 years; 60% female), or pegcetacoplan (mean age: 45 years; 62% female). More patients in the ravulizumab cohort were complement inhibitor-naive (31%) compared with eculizumab (20%) or pegcetacoplan (24%). Mean (standard deviation [SD]) duration of follow-up was 25.3 (15.9), 33.5 (18.9) and 13 (8.0) months, and mean (SD) proportion of days covered (PDC) was 0.98 (0.05), 0.90 (0.14) and 0.77 (0.30) for the ravulizumab, eculizumab and pegcetacoplan cohorts, respectively. The percentage of patients with PDC ≥ 0.8 (a widely used threshold for treatment adherence) was 98.5% for ravulizumab, and 84.5% and 78.4% for eculizumab and pegcetacoplan, respectively. The median (interquartile range [IQR]) duration on ravulizumab treatment was 48.4 (11.5, not reached [NR]) months, compared with 7.6 (3.4, 23.3) for eculizumab and 14.6 (0.2, NR) for pegcetacoplan. Among patients with ≥ 12 months on ravulizumab treatment (n = 183), a 24.8% reduction in all-cause HRU was observed during the first 12 months of treatment compared with the prior 12 months. Statistically significant reductions were observed in mean (SD) all-cause hospitalizations (0.2 [0.6] PPPY during follow-up; % difference -44.6%, p = 0.014), outpatient visits (24.3 [17.8] PPPY; % difference -19.1%, p < 0.001) and emergency room visits (0.5 [1.3] PPPY; % difference -39.8%, p = 0.008). Similar results were observed for PNH-related HRU, including a 32.1% reduction in the overall number of visits (p < 0.001). Notably, a statistically significant reduction in PNH-related hospitalizations (0.2 [0.5] PPPY; % difference -37.8%, p = 0.044) and outpatient visits (14.3 [10.7] PPPY; % difference -22.4%, p < 0.001) was observed. Ravulizumab initiation was also associated with fewer PNH-related emergency room visits (0.2 [0.7] PPPY; % difference -32.7%, p = 0.170) and blood transfusions (0.8 [2.9] PPPY; % difference -30.7%, p = 0.277); however, these changes were not statistically significant. Conclusions In this retrospective analysis, patients demonstrated higher adherence and persistence to ravulizumab treatment compared to other complement inhibitors. HRU decreased following ravulizumab initiation, indicating an alleviated burden of disease in these patients after treatment initiation. These real-world data provide further evidence of the benefit of ravulizumab in patients with PNH.