Lemtrada Treatment Effects in MS Patients Maintained Over Seven Years

Patients with relapsing remitting multiple sclerosis (RRMS) who received Sanofi Genzyme’s Lemtrada (alemtuzumab) experienced effects of treatment on disease activity that were maintained over seven years, according to data from the extension of two pivotal studies.

Among RRMS patients treated with Lemtrada in the two-year CARE-MS pivotal studies, 80 percent (n=299) from CARE-MS I and 73 percent (n=317) from CARE-MS II completed long-term follow-up through year seven. Key findings include:

• After the initial two courses of Lemtrada, which patients received upon study entry and 12 months later, 59 percent (n=206) of Lemtrada patients from CARE-MS I and 47 percent (n=185) from CARE-MS II received no further treatment during the following six years. Patients were eligible to receive either retreatment with Lemtrada or treatment with another MS disease-modifying therapy.
• The annualized relapse rates observed in patients who received Lemtrada in CARE-MS I (0.18) and CARE-MS II (0.26) remained low throughout the extension (0.13 and 0.14 at year seven.)
• At year seven, 74 percent and 69 percent of Lemtrada-treated patients from CARE-MS I and CARE-MS II, respectively, did not experience confirmed disability worsening1; 37 percent and 44 percent, respectively, experienced confirmed disability improvement.
• Through year seven, patients who received Lemtrada in CARE-MS I and II experienced a slowing of brain volume loss. In years three through seven, the median yearly brain volume loss was -0.20 percent or less, which was lower than what was observed in the Lemtrada-treated patients during the pivotal studies (CARE-MS I: -0.59 percent in year one; -0.25 percent in year two; CARE-MS II:-0.48 percent in year one; -0.22 percent in year two).
• In each year through year seven, most patients had no evidence of magnetic resonance imaging (MRI) disease activity4 (CARE-MS I: 66 – 77 percent; CARE-MS II: 67 – 76 percent).
• Through year seven, the yearly incidence of most adverse events during the extension was comparable or reduced compared with the pivotal studies. The frequency of thyroid adverse events was highest in year three (CARE-MS I: 15 percent; CARE-MS II: 17 percent) and generally declined thereafter. There were three deaths in year seven, none of which was considered related to Lemtrada by the study investigators.

Lemtrada is a monoclonal antibody that binds to CD52, a protein present on the surface of mature lymphocytes, but not on the stem cells from which these lymphocytes are derived. After treatment with alemtuzumab, these CD52-bearing lymphocytes are targeted for destruction. Many of these are believed to be the white blood cells that attack the central nervous system in people with MS.