Efficacy and Safety of Intravenous Immunoglobulin (IVIG) IgPro10 in Chronic Inflammatory Demyelinating Polyneuropathy (CIDP): the PRIMA and PATH studies (P1.153)

Objective: Analyze the efficacy and safety of IVIG IgPro10 (CSL Behring) in 2 trials of CIDP. Background: IgPro10 (recently approved for CIDP in the US) was investigated in a small study (PRIMA), and subsequently in the larger PATH study. Design/Methods: PRIMA was a prospective, open-label, single-arm study in 28 CIDP patients (n=13 IVIG-pretreated; n=15 untreated) investigating efficacy and safety of IgPro10 for induction (2g/kg) and maintenance therapy (1g/kg every 3 weeks for 21 weeks). This regimen was also used for 207 IVIG-pretreated patients during the 10–13 week pre-randomization phase of the PATH study (before randomization to subcutaneous immunoglobulin maintenance therapy or placebo). Both studies investigated a 1-point decrease in adjusted Inflammatory Neuropathy Cause and Treatment (INCAT) disability score as a response parameter, and evaluated changes in mean grip strength and Medical Research Council (MRC) score. Treatment-emergent adverse events (AEs) were assessed. Results: Response rate was 76.9% (95% confidence interval [CI]: 49.7–91.8) in PRIMA (IVIG-pretreated patients) at week 21 and 72.9% (95% CI: 66.5–78.5) in PATH at week 13; median time to first INCAT response was 3.0 and 3.7 weeks, respectively. Median (Q1;Q3) improvements in outcome measures (baseline to last observation) for PRIMA pre-treated patients and PATH, respectively, were: INCAT, −2.0 (−3.0; −1.0) and −1.0 (−2.0;0.0) points; grip strength, 5.0 (−9.0;22.0) and 9.4 (1.3;18.8) kPa; and MRC score, 5.0 (3.0;10.0) and 3.0 (0.0;6.0) points. In the PRIMA safety population (n=28), 108 AEs occurred in 22 (78.6%) patients (0.417/infusion); 284 AEs in 100 (48.3%) patients (0.175/infusion) were reported in the PATH safety population (n=207). Headache was the most frequent AE. Causally-related serious AEs in PRIMA and PATH occurred in 2 and 7 patients, respectively. Conclusions: Similar efficacy results of IgPro10 in CIDP were observed in PRIMA and the PATH pre-randomization period. IgPro10 is well tolerated, with clinically meaningful improvement in disability in CIDP patients. Study Supported by: CSL Behring Disclosure: Dr. Mielke has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with CSL Behring GmbH. Dr. Van Schaik has received personal compensation in an editorial capacity for Cochrane Neuromuscular Disease Group. Dr. Van Schaik has received research support from CSL Behring; Baxter. Dr. Leger has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Baxalta; CSL Behring; Kedrion; LFB; Novartis; UCB; Terumo-BCT; Pfizer. Dr. Leger has received personal compensation in an editorial capacity for Masson-Elsevier; Wiley Blackwell; Wolters Kluwer. Dr. Leger has received research support from CSL Behring; LFB; Novartis. Dr. Bril has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Octapharma, Grifols, CSL, UCB. Dr. van Geloven has received research support from CSL Behring. Dr. Hartung has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Biogen Idec, GeNeuro, Sanofi Genzyme, Merck, Novartis Pharmaceuticals, Octapharma, Opexa Therapeutics, Teva Pharmaceuticals, MedImmune, Bayer HealthCare, Forward Pharma, and Roche. Dr. Lewis has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with CSL Behring; Axelacare; Pharnext; Biotest; Kedrion; Nufactor; Optioncare; Grifols. Dr. Lewis has received research support from Neutralis; Cytokinetics. Dr. Sobue has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Mitsubishi Tanabe Pharma Co; Shionogi Co Ltd; Bristol Myers Squibb; Sumitomo Dainippon Pharma Co Ltd; Novartis Pharma KK; Bayer Yakuhin Ltd; Pfizer Japan Inc; Boehringer Ingelheim Japan Inc; Kissei Pharmaceutical Co Ltd; Janssen Pharmaceutical KK; Teijin. Dr. Lawo has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with CSL Behring GmbH. Dr. Durn has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with CSL Behring. Dr. De Bleecker has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Pfizer;Sanofi-Genzyme; CSL Behring. Dr. Cornblath has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Acetylon Pharmaceuticals Inc; Alcobra Pharma; Alnylam Pharmaceuticals; Annexon Biosciences; Akros Pharma; Biotest; Boehringer Ingelheim; Cigna Health Management Inc; CSL Behring; DP Clinical Inc; GLAXOSMITHKLINE Plc; Grifols S.A.; Hansa Medical Inc; Karos. Dr. Cornblath has received royalty, license fees, or contractual rights payments from Acetylon Pharmaceuticals Inc; AstraZeneca Pharmaceuticals LP; Calithera Biosciences; Genentech Inc; Neurocrine Biosciences; Merrimack Pharmaceuticals Inc; Seattle Genetics, Inc; Shire Development, LLC. Dr. Sommer has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Alnylam; Baxalta; CSL Behring; Genzyme; Grifols; Kedrion; Pfizer; UCB. Dr. Sommer has received research support from Kedrion. Dr. Robberecht has received research support from CSL Behring. Dr. Saarela has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with CSL Behring; Sanofi Genzyme. Dr. Kamienowski has nothing to disclose. Dr. Stelmasiak has nothing to disclose. Dr. Tackenberg has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Bayer Healthcare, Biogen, CSL Behring, GRIFOLS, Merck Serono, Novartis, Octapharma, Roche, Sanofi Genzyme, TEVA und UCB Pharma. Dr. Tackenberg has received personal compensation in an editorial capacity for Frontiers Neurology. Dr. Tackenberg has received research support from Biogen, Novartis, Merck. Dr. Merkies has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Talecris. Dr. Merkies has received personal compensation in an editorial capacity for Journal of Peripheral Nervous System.