The availability of both intravenous and subcutaneous routes of immunoglobulin has made personalization of treatment more important than ever.
Although subcutaneous immunoglobulin (SCIG) is an option for maintenance therapy in patients with chronic inflammatory demyelinating polyneuropathy (CIDP), a study analysis published in the Journal of the Neurological Sciences shows that more participants showed improved disability at 24 weeks when receiving intravenous immunoglobulin (IVIG).
CIDP is an acquired neurological disorder characterized by weakness and impaired sensory function evolving over 2 months or more, loss or a significant decrease in deep tendon reflexes, and electrophysiological evidence of peripheral nerve demyelination. According to the study authors, early diagnosis and treatment of CIDP is essential to avoid irreversible damage and disability.
IVIG is an option for both first-line and maintenance CIDP therapy, and the 2018 FDA approval of SCIG in this population provides more treatment options for maintenance therapy. Other first-line options with proven efficacy include corticosteroids and plasmapheresis. The authors said these different options for IG administration necessitate more information to assist clinicians and patients when choosing their approach.
Based on 5 randomized, placebo-controlled trials between 1993 and 2008, investigators have established the efficacy and safety of IVIG. According to the authors, the most informative trial was Intravenous Immunoglobulin for the Treatment of Chronic inflammatory Demyelinating Polyradiculoneuropathy (ICE study), which compared IVIG administered as a 2 g/kg loading dose followed by a 1 g/kg maintenance dose every 3 weeks to a placebo. The study included 117 patients and had a primary outcome measure of improvement from baseline in disability by 6 weeks and maintained through 24 weeks.
According to the analysis, the percentage of patients with improved disability at 24 weeks was significantly greater in the IVIG group compared with the placebo group (54% and 21%, respectively). Furthermore, 60% of IVIG responders achieved maximal response by week 6, in addition to significant improvements in muscle strength and grip strength.
Finally, the authors found 55% of patients receiving IVIG reported a drug-related adverse event (AE), compared with 17% of patients receiving the placebo. The most commonly reported IVIG-associated adverse events were headache, pyrexia, and hypertension. Serious AEs were reported in 5% of IVIG patients and 8% of placebo patients.
Despite these encouraging findings for IVIG treatment, the review authors said that the availability of both IV and SC routes has made personalization of treatment more important than ever.
“While selection of IVIG or SCIG is ultimately a choice best left to the discretion of each patients and their treating physician, several factors warrant consideration so that patients can make informed decisions that best balance their needs, preferences, and lifestyles,” the authors wrote.
These factors include pharmacokinetics, AE profiles, the site of care available to the patient, dosing and frequency of administration, infusion rate and duration, and patient preference variables. Clinicians should consider and discuss all of these factors with patients in order to ensure that every patient is treated individually and receives the care that works best for them.
“The decision to use SCIG and IVIG is one that is best individualized to each patient’s disease characteristics, treatment goals, and lifestyle,” the authors concluded. “There is no ‘best’ method to determine which route of administration is optimal for every patient. Health care providers are uniquely positioned to help patients work through these complex issues. Ultimately, the decision is a personal one that ideally maximizes efficacy, tolerability, and quality of life.”
Allen J, Gelinas D, Freimer M, Runken M, and Wolfe G. Immunoglobulin administration for the treatment of CIDP: IVIG or SCIG? Journal of the Neurological Sciences; November 9, 2019. https://www.jns-journal.com/article/S0022-510X(19)30429-0/fulltext. Accessed November 4, 2020.