PURPOSE:Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a rare autoimmune condition of the peripheral nervous system. The validity of the CIDP diagnosis code in claims data is unclear. METHODS:We conducted a validation study testing the performance of claims-based algorithms in identifying CIDP cases, using electronic health record data from the Mass General Brigham Integrated Health Care System linked with Medicare claims data from 01/01/2008 to 12/31/2020. The algorithms require a record of intravenous immunoglobulin (IVIG) use and International Classification of Diseases 9th/10th Revision (ICD9/10) CIDP codes before (including) the date of IVIG use. The positive predictive values (PPVs) of each claims-based algorithm were calculated against the reference standard for CIDP and chronic immune-mediated acquired neuropathy established through chart review by two board-certified neurologists using a standardized abstraction tool. RESULTS:The study cohort consisted of 140 patients (59 in the ICD9 and 81 in the ICD10 era). The PPV of the algorithm requiring at least one CIDP diagnosis code before IVIG use was 66.2% (95% confidence interval [CI], 58.0-74.3). The PPV improved to 71.2% (62.7-79.6) when requiring at least two CIDP codes before IVIG use. The PPV for patients with at least one CIDP code who met the European Academy of Neurology/Peripheral Nerve Society 2021 diagnostic criteria was 30.0% (22.1-37.9). CONCLUSION:We found that a patient cohort identified using claims-based CIDP diagnoses included a substantial number of patients with other chronic inflammatory acquired neuropathies not formally recognized as CIDP by clinical consensus criteria. Requiring two CIDP codes can improve PPVs.

To evaluate long-term safety and efficacy of facilitated subcutaneous immunoglobulin (fSCIG; human immunoglobulin G [IgG] 10% with recombinant human hyaluronidase) in patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP).

Purpose Facilitated subcutaneous immunoglobulin (fSCIG; immune globulin infusion 10% [human] with recombinant human hyaluronidase [rHuPH20]) permits high-volume subcutaneous immunoglobulin (SCIG) infusion, shorter infusion times and reduced dosing frequency relative to conventional SCIG. It is initiated by gradually increasing infusion volumes over time (dose ramp-up) to achieve target dose level (TDL). Whether ramp-up strategies have tolerability or safety advantages over direct initiation at full TDL has not been evaluated clinically.Methods This phase 1 open-label study assessed tolerability and safety of fSCIG 10% with accelerated or no ramp-up compared with conventional ramp-up in healthy adults (NCT04578535). Participants were assigned to one of the three ramp-up arms to achieve TDLs of 0.4 or 1.0 g/kg/infusion. The primary endpoint was the proportion of infusions completed without interruption or infusion rate reduction owing to treatment-emergent adverse events (TEAEs). Safety was assessed as a secondary endpoint.Results Of 51 participants enrolled, 50 (98.0%) tolerated all fSCIG 10% infusions initiated (n = 174). Infusion rate was reduced in one participant owing to headache in the 0.4 g/kg/infusion conventional ramp-up arm. Study discontinuations were higher in the no ramp-up arm (70%) versus the conventional (0%) and accelerated (22%) arms at the 1.0 g/kg/infusion TDL. Safety outcomes did not substantially differ between treatment arms.Conclusion The favorable tolerability and safety profiles of fSCIG 10% in healthy participants support initiating treatment with fSCIG 10% with accelerated ramp-up at TDLs up to 1.0 g/kg. Data support no ramp-up at TDLs close to 0.4 g/kg but additional data are needed for higher doses.

To determine the effect of facilitated subcutaneous immunoglobulin (fSCIG; human immunoglobulin G 10% with recombinant human hyaluronidase) on patient-reported outcomes (PROs) in a Phase 3, randomized, placebo-controlled, double-blind, multicenter study (ADVANCE-CIDP 1; NCT02549170).

BACKGROUND AND AIMS:Hyaluronidase-facilitated subcutaneous immunoglobulin (fSCIG) consists of subcutaneous human immunoglobulin G (IgG) 10% with recombinant human hyaluronidase (rHuPH20) and can be administered at the same dose and interval as intravenous IgG (IVIG). fSCIG recently received US approval as maintenance therapy for adults with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and European approval for adults and children with CIDP after stabilization with IVIG. METHODS:ADVANCE-CIDP 3 (NCT02955355) was an open-label long-term extension of the Phase 3 double-blind randomized placebo-controlled ADVANCE-CIDP 1 study (NCT02549170) that examined fSCIG safety and efficacy as maintenance CIDP therapy. Primary outcomes were safety, tolerability, and immunogenicity. Efficacy was an exploratory outcome. RESULTS:The study provided 220 patient-years of follow-up data from 85 patients. Median (range) exposure was 33 (0-77) months. Patients received fSCIG every 4 weeks (88.2%) or every 3 weeks (11.8%). Median (range) 4-weekly IgG dose equivalent was 64.0 (28.0-200.0) g. Mean (standard deviation) infusion duration was 135.5 (62.8) minutes. Most adverse events (AEs) were mild or moderate and self-limiting. Of the 1406 AEs, only 48 were severe and 30 were serious. fSCIG-related AEs (n = 798) included infusion site reactions such as pain, redness, and pruritus. Three infusions (0.1%) were reduced in rate, interrupted, or stopped due to intolerability. Relapse occurred in 10 of 77 patients (13.0%); annual relapse rate was 4.5%. An anti-rHuPH20 antibody titer ≥1:160 was detected in 14 of 84 patients (16.7%); patients who tested positive (≥1:160) had similar relapse rates versus those who tested negative (16.7% vs. 12.3%, respectively). INTERPRETATION:ADVANCE-CIDP 3 demonstrated favorable fSCIG long-term safety and tolerability consistent with its established safety profile, and a low relapse rate, supporting use as maintenance CIDP treatment.

Facilitated subcutaneous immunoglobulin (fSCIG; immune globulin infusion 10

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a rare progressive or relapsing inflammatory disease. Intravenous immunoglobulin (IVIG) is recommended as a first-line therapy. The aim of this study was to describe real-world treatment patterns and outcomes of patients with CIDP in the Define initiating IVIG treatment. This cohort study used health insurance claims data from the Merative MarketScan Research Databases (2008–2018). Adult patients (≥ 18 years old) with CIDP without prior immunoglobulin treatment were identified using International Statistical Classification of Diseases and Related Health Problems (ICD) codes, and patients subsequently initiating IVIG were included in the analysis. Real-world IVIG treatment patterns and treatment and safety outcomes (assessed via ICD codes) were described. In total, 3975 patients (median age 58 years) with CIDP who initiated IVIG were identified. After the initial IVIG loading period, patients received IVIG at a median dosing interval of 21 days (quartile [Q]1, Q3: 7, 28), and continued treatment for a median of 129 days (Q1, Q3: 85, 271). After the 2-year follow-up period, 55

Intravenous immunoglobulin (IVIG) is recommended as first-line therapy for chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), an immune-mediated neuropathy. The clinical profile of patients with CIDP newly initiating IVIG is poorly characterized. This claims-based cohort study describes characteristics of US patients with CIDP initiating IVIG treatment. Adult immunoglobulin (IG)-naïve patients with CIDP diagnosed between 2008 and 2018 and a subgroup of patients subsequently initiating IVIG were identified in the Merative MarketScan Research Databases. Demographics, clinical characteristics, and diagnostic procedures were described for patients initiating IVIG. Of 32,090 patients with CIDP identified, 3975 (mean age 57 years) subsequently initiated IVIG. In the 6 months prior to IVIG initiation, diagnoses of comorbidities including neuropathy (75

ADVANCE‐CIDP 1 evaluated facilitated subcutaneous immunoglobulin (fSCIG; human immunoglobulin G 10% with recombinant human hyaluronidase) efficacy and safety in preventing chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) relapse.