Interim results from an extension trial of Sanofi/Genzyme’s Lemtrada in multiple sclerosis (MS) suggest the drug has a durable effect on relapse rates and disability progression.
The active ingredient in Lemtrada – alemtuzumab – was previously sold as a treatment for chronic lymphocytic leukaemia under the Campath brand name but was taken off the market for commercial reasons last year.
Sanofi and Genzyme believe there is considerably more potential for the drug as an MS therapy, perhaps as much as $3bn at peak, and the firms have already submitted it for approval in the US and Europe, with decisions expected by regulators later this year.
The new data – from the first 12 months of the ongoing extension study – showed that more than half of patients who had taken part in the pivotal CARE-MS I and CARE-MS II Lemtrada trials did not experience relapses after completing two courses of drug treatment.
Overall, 67 per cent of patients in CARE-MS I and 55 per cent of patients in CARE-MS II remained relapsed-free throughout the first year of the ongoing extension study, and more than 80 per cent of patients did not require any further treatment with Genzyme’s drug.
Lemtrada was administered in the CARE-MS studies as a five-day intravenous infusion, with a second three-day course given 12 months later. That once-yearly dosing regimen could differentiate it in the marketplace from other injectable MS drugs such – notably beta interferons – that need to be taken more often.
“These findings are important because they suggest that the benefits of Lemtrada as observed in the Phase III studies are maintained, even though most patients did not receive further dosing,” said MS specialist Edward Fox, who presented the results at the annual meeting of the American Academy of Neurology this week.
In the US, the FDA issued a refuse-to-file letter for Lemtrada last September because of the way the data was presented in the dossier, but Sanofi re-filed the application and said that it expects the FDA to announce its decision on whether to approve the medicine in the second half of 2013.
If approved Lemtrada will add to Sanofi’s MS franchise, currently represented by oral therapy Aubagio (teriflunomide) which was cleared for marketing in the US last year. The drug was originally acquired from Bayer, which retains a co-promotion option in MS.