Lemtrada Does Not Lead to Brain Bleeds, Small Belgian Study Says
Lemtrada (alemtuzumab) does not have a substantial effect on blood pressure or platelet counts, and does not lead to bleeding in the brain of multiple sclerosis (MS) patients, according to a small Belgian study.
The findings contrast with previous studies showing an increase in blood pressure, stroke, and brain bleeding as serious adverse reactions in people taking Lemtrada. Differences in patient characteristics and treatment regimens should be explored, the researchers said.
The study, “Alemtuzumab in multiple sclerosis: retrospective analysis of occult hemorrhagic MRI lesions and risk factors,” was published in the European Journal of Neurology.
Lemtrada is a widely approved therapy to slow the progression of relapsing-remitting multiple sclerosis (RRMS). Recently, studies have reported that, in rare cases, the medication can cause intracranial hemorrhage (bleeding in the brain) or stroke, which can be fatal.
Risk factors for these rare but serious side effects are unclear, but some have pointed to an increase in blood pressure, platelet disorders, or an abnormal coagulation system.
In the new study, researchers at Ghent University Hospital and Sint-Jan Bruges Hospital, both in Belgium, conducted a retrospective review of 30 people with RRMS who were treated with Lemtrada at their institutions from 2016 to 2019. The patients had a mean average age of 40 years. Two-thirds were female, and all were white.
The researchers analyzed brain imaging data for 23 of the patients to look for evidence of microbleeds — small bleeding in the brain that is unlikely to cause overt health problems, but may be a harbinger of a future intracranial hemorrhage. The team found no evidence of microbleeds in any of the scans.
In separate analyses of 13 patients, the researchers looked at whether Lemtrada treatment was associated with changes in blood pressure. However, in contrast to previously reported data, there was no evidence that the medication led to significant changes in blood pressure, either on the day of administration or across days.
“These different results could be possibly explained by differences in population (age, cardiovascular risk) or in monitoring/infusion protocol (slower infusion rate, lower intravenous volume administration, in-hospital-setting vs ambulatory administration, adjuvant medication),” the researchers wrote, noting a need for more research.
They also looked at whether the medication affected levels of platelets — cell fragments involved in blood clotting — since decreased platelet counts (thrombocytopenia) can predispose patients toward excessive bleeding. Analyses of 20 patients showed only a mild reduction in thrombocyte counts following Lemtrada treatment, which the scientists said was unlikely to be of clinical relevance.
“In this retrospective study, treatment with alemtuzumab was not associated with arterial hypertension, relevant thrombocytopenia or (asymptomatic) hemorrhagic brain lesions,” the team concluded.
Lemtrada is made by Sanofi-Genzyme, which was not involved in this study.