Despite likely new MS drugs, US neurologists continue to see significant near-term growth for Tysabri and Gilenya

Within the multiple sclerosis treatment arena, the availability of the anti-JC virus antibody assay appears to be contributing to the significant increase in overall satisfaction with Biogen Idec (Nasdaq: BIIB) and Elan’s (NYSE: ELN) Tysabri (natalizumab), over the past year.

According to the recently published TreatmentTrends: Multiple Sclerosis (US) Q2 2012 report from Decision Resources’ BioTrends Research Group, just under one-half of US neurologists believe that the anti-JC virus antibody assay has had a positive impact on both their willingness to prescribe Tysabri and on their comfort with the risk-benefit profile of Tysabri. While disease-modifying agent (DMA) brand shares among DMA-treated patients have remained relatively stable compared to previous quarters, Tysabri’s share among secondary progressive multiple sclerosis (SPMS) patients has increased significantly over the past year (9% to 17%), primarily at the expense of Teva’s (Nasdaq: TEVA) Copaxone (glatiramer acetate).

The report also finds that more than three-quarters of neurologists report being aware (unaided) of recent news related to Novartis’s (NOVN: VX) Gilenya (fingolimod), with most mentions focusing on the recent label changes and/or reports of sudden or unexplained deaths in Gilenya-treated patients.