Intravenous Immunoglobulin Treatment Patterns and Outcomes in Patients with Chronic Inflammatory Demyelinating Polyradiculoneuropathy: A US Claims Database Analysis

Neurol Ther. 2023 Aug;12(4):1119-1132. doi: 10.1007/s40120-023-00478-5. Epub 2023 May 12.

Abstract

Introduction: 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.

Methods: 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.

Results: 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% of patients had discontinued all IVIG treatment; more than one-half of these discontinuations occurred within 4 months. Diagnoses of impaired functional status were evident in more than 30% of patients at baseline, but at lower rates during follow-up. Rates of new-onset safety outcomes after IVIG treatment were low.

Conclusion: This real-world analysis of IVIG treatment patterns and treatment and safety outcomes of patients with CIDP who initiated IVIG highlights the unmet need for improved long-term management. Further research is needed to evaluate the use of functional status measures as endpoints for immunoglobulin treatment effectiveness.

Keywords: CIDP; Chronic inflammatory demyelinating polyradiculoneuropathy; Claims database; IVIG; Intravenous immunoglobulin; Safety; Treatment.

Plain language summary

Chronic inflammatory demyelinating polyradiculoneuropathy, also called CIDP, is a rare disease that causes the body’s immune system to attack its nerves. Treatments for CIDP include antibodies, which are also called immunoglobulins. Immunoglobulins may be given intravenously, meaning they are administered into a vein. Intravenous immunoglobulin, also called IVIG, is recommended as one of the first treatments that patients with CIDP receive in their therapy and involves giving antibodies through a drip into a vein. This study aimed to gather information on the day-to-day use of IVIG by patients with CIDP. Information from 2008 to 2018 was collected from a large health insurance database in the USA. Information was taken from the records of patients aged 18 years or older who had received IVIG during the information collection period. In total, records from 3975 patients with an average age of 58 years were included in the study. On average, patients received IVIG every 21 days for 129 days. By 2 years, 55% of patients had stopped receiving IVIG; most of those patients had stopped within 4 months of first receiving the treatment. In the 6 months before receiving IVIG, over 30% of patients experienced limitations owing to their CIDP that affected their daily lives, although this percentage became smaller once patients started to receive IVIG. In addition, a low number of patients experienced side effects because of their IVIG treatment. This study highlights that improved long-term care for patients with CIDP is needed. Further research into ways of measuring the impact of CIDP on patients’ daily lives is required, which may help doctors to work out how effective IVIG is at treating CIDP.