IVIG Plus IVMP Does Not Increase Remission Rates in CIDP Patients

According to a recent study, adding intravenous methylprednisolone (IVMP) to intravenous immune globulin (IVIG) induction therapy does not significantly increase remission rates among patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP).

In the randomized, double-blind, placebo-controlled study, investigators enrolled adults with probable or definite CIDP at neuromuscular centers in the Netherlands and the United Kingdom. Eligible participants included treatment-naïve patients, those who relapsed after at least one year of remission or individuals who deteriorated following an initial IVIG loading dose.

Participants were randomly assigned to receive either IVIG plus IVMP (1,000 mg every three weeks) or IVIG plus placebo during an 18-week treatment period. All patients received an IVIG loading dose of 2 g/kg followed by maintenance infusions of 1 g/kg. The primary endpoint was remission at 52 weeks, defined as sustained improvement on disability measures without the need for additional CIDP treatment.

A total of 77 participants were randomized before the trial was ended by the data safety monitoring board. Among these patients, 14 of 37 (38 percent) in the IVIG/IVMP group and 11 of 40 (28 percent) in the IVIG/placebo group achieved remission at 52 weeks. Secondary outcomes showed a similar proportion of participants improving during the treatment phase. Disability improvement at 18 weeks occurred in 73 percent of patients receiving IVIG plus IVMP compared with 68 percent receiving IVIG alone.

The median time to improvement was six weeks with combination therapy versus 12 weeks with IVIG alone. Investigators also reported that among patients who responded to treatment, those receiving the combined regimen often experienced greater overall improvement in disability and impairment scores.

Recruitment was stopped after investigators observed four thromboembolic events in the IVIG plus IVMP group, including three pulmonary embolisms and one deep venous thrombosis. No thromboembolic events occurred in the IVIG-placebo group. These events occurred despite mitigation strategies such as limiting IVIG infusion rates. Patients recovered after treatment with anticoagulants and did not experience long-term complications.

The findings suggest that adding corticosteroids to IVIG induction therapy does not meaningfully improve remission rates in CIDP using the dosing regimen studied.