Lemtrada May Slow MS Disease Progression, Long-term Study Suggests
Lemtrada (alemtuzumab) may slow the progression of multiple sclerosis (MS) and lower the conversion rate of relapsing-remitting MS (RRMS) to secondary progressive MS (SPMS), a long-term study suggests.
The results showed that patients converting to SPMS — in which a person’s disability gets steadily worse — were older, had longer disease duration, and had greater brain lesions.
The study, “Proportion of alemtuzumab-treated patients converting from relapsing-remitting multiple sclerosis to secondary progressive multiple sclerosis over 6 years,” was published in the Multiple Sclerosis Journal – Experimental, Translational and Clinical.
Most people with RRMS will eventually convert to SPMS, and this conversion is an important predictor of long-term prognoses in patients. The development of disease-modifying treatments capable of lowering the relapse rate and treating MS symptoms has allowed for fewer people to convert to SPMS and/or for this transition to occur later.
However, there still is little information concerning how current treatments such as Lemtrada — an approved MS therapy marketed by Sanofi-Genzyme — may delay this conversion.
To fill this knowledge gap, a multi-national research team determined the proportion of patients treated with Lemtrada who converted from RRMS to SPMS during the CARE-MS Phase 3 trials and an extension study. In total, CARE-MS I (NCT00530348), CARE-MS II (NCT00548405), and the extension (NCT00930553) spanned six years.
These studies compared Lemtrada’s effectiveness with that of Rebif (interferon beta-1a) in patients with RRMS not undergoing treatment (CARE-MS I, ages 18-50 years) or with inadequate response to an earlier therapy (CARE-MS II, ages 18-55 years).
In these trials, participants received 12 mg doses of Lemtrada (intravenously, or into the vein) for five consecutive days at the start of the study and at three consecutive days one year later.
Those completing the Phase 3 trials could enter the four-year CARE-MS extension study to receive additional Lemtrada treatment. Patients treated with Rebif who entered this extension study switched to Lemtrada.
The present study included 811 CARE-MS patients, with a mean age of 34.0 years, who were treated with Lemtrada only, and 282 individuals — mean age of 34.5 years — treated with Lemtrada and Rebif. From these, 669 patients treated with Lemtrada (82%) and 245 treated with Lemtrada and Rebif (87%) completed the six-year follow-up.
Over that follow-up period, 20 patients (2.7%) treated with Lemtrada converted to SPMS, as measured by the expanded disability status scale (EDSS) and using a confirmation period of three months. The median time for conversion was 37.5 months (just over three years).
Notably, an additional sensitivity analysis accounting for CARE-MS patients who did not have full 6-year data showed similar results.
From the beginning of the study, patients converting to SPMS were older than those who did not convert (36.6 vs. 33.9 years), had higher EDSS scores (meaning greater disability; 3.4 vs. 2.4), greater brain lesion volume, and longer disease duration (4.6 vs. 3.3 years).
The researchers noted several limitations to their study, including the lack of a consensus diagnostic criteria for SPMS, the lack of a comparator for rates of SPMS conversion, and limited follow-up time.
Nonetheless, although further confirmation of the results over longer time periods and in real-world groups will be important, the “data suggest alemtuzumab [Lemtrada] may affect the natural history of MS by slowing progression to more severe stages of the disease,” the researchers wrote.
“The 6-year conversion rate to secondary progressive MS was low for alemtuzumab-treated patients, supporting further study of the role alemtuzumab may play in reducing risk of secondary progression,” the team concluded.