Genzyme, a Sanofi company, has announced new magnetic resonance imaging (MRI) data from the Lemtrada (alemtuzumab) clinical development program. In Lemtrada patients from the two Phase III clinical trials (both treatment-naïve patients and patients who had active disease on another therapy), MRI effects observed after two years were maintained during the first year of the extension study. These data, which are being presented at the 66th American Academy of Neurology (AAN) Annual Meeting, include:

  • Consistent effects were seen across key measures of disease activity (gadolinium (gd)-enhancing, T2 hyperintense and T1 hypointense lesion activity) and effects seen after two years of treatment were sustained at year three.
  • During the third year of follow-up, more than 70% of patients were free of MRI activity indicative of acute inflammation, defined as gd-enhancing or new or enlarging T2 hyperintense lesions.
  • T2 lesion volumes, which reflect the combined burden of permanent brain injury and new lesion formation, increased from year two to three but remained below pre-treatment baseline.
  • The rate of atrophy, as measured by brain parenchymal fraction, already reduced after two years, continued to slow in the third year of follow-up.
  • Approximately 80 percent of patients treated with Lemtrada did not receive a third course of treatment in the first year of the extension.

"What's remarkable about these data is that the positive MRI effects of Lemtrada were sustained into the extension study, even though most patients did not receive additional Lemtrada treatment. This observation is unique amongst the current landscape of MS therapeutics," said Douglas Arnold, M.D., NeuroRx Research and Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University. "The new MRI results are an important addition to the clinical data from the extension study that demonstrated Lemtrada's effect on key measures of clinical disease activity including annualized relapse rates and sustained accumulation of disability."

The most common side effects of Lemtrada are infusion associated reactions (headache, rash, pyrexia, nausea, fatigue, urticaria, insomnia, pruritus, diarrhea, chills, dizziness, and flushing), infections (upper respiratory tract and urinary tract), and lymphopenia. Autoimmune conditions (including immune thrombocytopenia, other cytopenias, glomerulonephritis and thyroid disease) and serious infections can occur in patients receiving Lemtrada. A comprehensive risk management program incorporating education and monitoring will support early detection and management of these identified risks. Safety results from the first year of the extension study were previously reported for patients who received Lemtrada in the Phase III CARE-MS studies. No new risks were identified. As previously reported, there were two deaths in the extension study. One was from sepsis and the other was presumed accidental and deemed unrelated to study treatment.

The Phase III trials of Lemtrada were randomized, two-year studies comparing treatment with Lemtrada to high-dose subcutaneous interferon beta-1a (Rebif®) in patients with RRMS who had active disease and were either new to treatment (CARE-MS I) or who had relapsed while on prior therapy (CARE-MS II). In these studies, patients on Lemtrada received two courses of treatment, the first administered via intravenous infusion on five consecutive days, and the second administered on three consecutive days, 12 months later.

Lemtrada-treated patients who continued uninterrupted follow-up in the extension study were eligible for re-treatment on evidence of disease activity. This analysis included 349 Lemtrada-treated patients from CARE-MS I and 393 Lemtrada-treated patients from CARE-MS II; 18 percent and 20 percent, respectively, received re-treatment. MRI scans were taken at CARE-MS baseline, and at 12, 24, and 36 months.

"Given the importance of MRI in measuring disease activity in MS, the Lemtrada data announced today are significant," said Genzyme President and CEO, David Meeker, M.D. "These results reinforce the potential that Lemtrada holds to transform the treatment of MS."

In CARE-MS I, Lemtrada was significantly more effective than interferon beta-1a at reducing annualized relapse rates; the difference observed in slowing disability progression did not reach statistical significance. In CARE-MS II, Lemtrada was significantly more effective than interferon beta-1a at reducing annualized relapse rates, and accumulation of disability was significantly slowed in patients given Lemtrada vs. interferon beta-1a.

About LemtradaTM (alemtuzumab)

Lemtrada is approved in the European Union, Australia, Brazil, Canada and Mexico. Lemtrada is currently not approved in the United States. Following constructive discussions with the FDA, Genzyme plans to resubmit in the second quarter of 2014 its application seeking U.S. approval of Lemtrada. The resubmission will provide information to specifically address issues previously noted by the FDA in its December 2013 Complete Response Letter. Marketing applications for Lemtrada are also under review in other countries. Lemtrada is supported by a comprehensive and extensive clinical development program that involved nearly 1,500 patients and 5,400 patient-years of follow-up.

Alemtuzumab is a monoclonal antibody that selectively targets CD52, a protein abundant on T and B cells. Treatment with alemtuzumab results in the depletion of circulating T and B cells thought to be responsible for the damaging inflammatory process in MS. Alemtuzumab has minimal impact on other immune cells. The acute anti-inflammatory effect of alemtuzumab is immediately followed by the onset of a distinctive pattern of T and B cell repopulation that continues over time, rebalancing the immune system in a way that potentially reduces MS disease activity.

Genzyme holds the worldwide rights to alemtuzumab and has primary responsibility for its development and commercialization in multiple sclerosis. Bayer HealthCare holds the right to co-promote alemtuzumab in MS in the United States. Upon commercialization, Bayer will receive contingent payments based on global sales revenue.