[P06.130] Oral Masitinib in Patients with Primary Progressive or Secondary Progressive Multiple Sclerosis

Patrick Vermersch, Lille, France, Rabah Benrabah, Paris, France, Nicolas Schmidt, Rueil-Malmaison, France, Hélène Zephir, Lille, France, Pierre Chen, Clermont-Ferrand, France, Cyrille Vongsouthi, Montpellier, France, Alain Moussy, Olivier Hermine, Paris, France

OBJECTIVE: To test masitinib in primary progressive and secondary progressive multiple sclerosis. BACKGROUND: Few therapeutic options exist for secondary progressive multiple sclerosis (SPMS) and none are available for primary progressive MS (PPMS). Masitinib, oral tyrosine kinase inhibitor, targets mast cells, which have been found in sites of inflammatory demyelination and are suspected to be involved in the early stages of MS. DESIGN/METHODS: Oral masitinib or placebo were given at 3 or 6 mg/ml/day, then at 6 mg/kg/day to patients with either PPMS or SPMS. Changes in disease activity were monitored using EDSS, MSFC, MRI measurements and quality of life assessment (MSQLI). RESULTS: Of the 35 patients enrolled, 27 received masitinib (10 PPMS and 17 SPMS patients) and 8 received placebo (5 PPMS and 3 SPMS patients). At month 3, patients receiving masitinib improved their MSFC z-scores while a worsening occurred in patients receiving placebo (+78% and -64%, respectively, p=0.321). Both PPMS and SPMS patients receiving masitinib improved their mean MSFC z-scores (+108% and +60%, respectively) whereas it worsened in patients receiving placebo (-14% and -113%, respectively). This improvement was sustainable until month 18 for PPMS and SPMS patients receiving masitinib (+134% and +73%, respectively) compared to PPMS and SPMS patients receiving placebo (-11% and -110%, respectively). This sustainable improvement was mainly driven by T25FW and 9-HPT. Over 18 months of treatment, EDSS scores remained stable in the PPMS population in both treatment groups, while in the SPMS population, EDSS scores remained stable in the masitinib group and increased by one point in the placebo group (p=0.055). Although not conclusive, MSQLI and MRI measurements showed positive changes in the masitinib group. CONCLUSIONS/RELEVANCE: This small population, proof of concept suggests that targeting mast cells could provide a therapeutic option for both PPMS and SPMS patients. Data give ground for a large scale phase 3 trial. Supported by: AB Science, SA
Category - MS and Related Diseases - Clinical Science

Wednesday, April 29, 2009 4:00 PM

Poster Session VI: Multiple Sclerosis: Therapeutics I (4:00 PM-7:00 PM)