New research suggests that rising blood pressure might be predictive of intracranial hemorrhage — bleeding in the brain, a serious and sometimes fatal condition — in people with multiple sclerosis (MS) who are receiving treatment with Lemtrada (alemtuzumab).
The study, titled “Intracerebral haemorrhage during alemtuzumab administration,” was published in the journal The Lancet Neurology. The study was partially funded by Sanofi Genzyme, the manufacturer of Lemtrada.
Lemtrada is a disease-modifying treatment for relapsing-remitting MS (RRMS). The usual dose is 12 mg per day, given in four-hour intravenous (into the vein) infusions over five consecutive days, followed by infusions on three consecutive days one year later. Lemtrada works by inactivating inflammatory immune B and T cells, which can help slow down the progression of MS.
However, treatment with Lemtrada carries risks, which is why the U.S. Food and Drug Administration (FDA) recommends it only for patients who have not responded well to other therapies. Among the concerns is that Lemtrada can cause internal bleeding.
Intracranial hemorrhage is an exceptionally dangerous, though relatively rare, version of such bleeding events.
Since Lemtrada’s approval in 2014, 13 cases of stroke and bleeding in the head and neck associated with the therapy have been reported worldwide.
The new study examined five additional cases of spontaneous intracranial hemorrhage that occurred at four MS centers in the U.S. during the initial 5-day course of Lemtrada administration.
All patients were female, had RRMS, were between 38 and 49 years of age, and had the disease for a relatively long time — 8 to 21 years. The women had previously tried at least two other therapies before being treated with Lemtrada, and none had a history of bleeding disorders or stroke.
All five patients suffered intracranial hemorrhage several hours after leaving the infusion clinic after the third (three patients), fourth, or fifth treatment infusions (one patient each). These events were detected due to symptoms that included decreased consciousness, confusion, and headache. All five patients required treatment in an intensive care unit.
Two of the patients recovered well, but three had lingering neurological problems after the event, unrelated to their MS.
In reviewing these cases, the researchers noticed that, in all but one, the patients’ blood pressure — measured at the infusion clinic as part of taking vitals — increased markedly.
This result was somewhat unexpected, since Lemtrada is usually thought to lower, not raise, blood pressure. Still, based on this observation, the researchers suggested that increased blood pressure may be a prelude to, or even a cause of, intracranial hemorrhage.
“We believe that patients whose mean systolic blood pressure increases by either 20 mmHg or more, or 20% or more throughout the infusion period, or who have a single blood pressure reading that is more than 20% higher than their baseline, might be at high risk of intracranial hemorrhage,” the researchers said.
More research is needed to determine a cause-and-effect relationship, the researchers said. But they suggest that patients at higher risk of brain bleeds should be monitored more closely and, if needed, treated effectively and in a more timely manner.
“If a rising blood pressure trend is observed, physicians could consider inpatient admission for close observation (eg, frequent vital signs and neurological checks, and strict blood pressure control) during alemtuzumab [Lemtrada] infusion, if the benefits of continuing to administer alemtuzumab are deemed to outweigh the potential risks,” the team concluded.