US neurologists' adoption of STRATIFY JCV has shifted Tysabri earlier in the treatment of some MS patients

In the USA, 77% of surveyed neurologists have experience with the STRATIFY JCV assay - commercially available since January 2012 to aid in progressive multifocal leukoencephalopathy (PML) risk stratification for multiple sclerosis (MS) patients treated with Biogen Idec/Elan’s Tysabri (natalizumab), according to BioTrends Research, a Decision Resources unit.

In the recently published Special Report: Impact of the Anti-JC Virus Antibody Assay, over one-half of neurologists agree that the assay has encouraged their use of Tysabri earlier in treatment, with 28% agreeing that they are comfortable prescribing Tysabri first line to a seronegative patient. In fact, serostatus significantly impacts neurologists’ perceptions of Tysabri’s risk-benefit profile, with 58% of neurologists perceiving Tysabri’s benefit outweighs its risks in seronegative patients compared to 13% of neurologists for seropositive patients.

Tysabri use among seropositive patients is mostly limited to those who have failed multiple disease-modifying agents (DMAs) or have very aggressive MS. Seropositive patients who are not willing to be treated with Tysabri are frequently considered candidates for Novartis’ Gilenya (fingolimod).