New treatment for multiple sclerosis shows promising results in clinical trials

By Amy Norton, HealthDay Reporter

An experimental antibody therapy for multiple sclerosis can reduce symptom flares by half compared with a standard treatment, according to a new clinical trial.

The drug, called ublituximab, outperformed a standard oral MS medication in reducing patients' relapses (periods of symptoms coming on or getting worse). It also proved better at preventing areas of inflammatory damage in the brain.

Ublituximab is not yet approved for the treatment of MS; the U.S. Food and Drug Administration is reviewing the trial data and is expected to make a decision by the end of the year, according to drugmaker TG Therapeutics.

If approved, ublituximab would be the latest in a new group of MS therapies called anti-CD20 monoclonal antibodies — lab-engineered antibodies that target specific immune system cells that drive the MS process.

The new findings provide further evidence that the approach benefits patients, according to an expert who was not involved in the trial.

“Is this revolutionary? No, but it is further confirmation of the clinical benefits of targeting this population of blood cells,” said Dr. Lauren Krupp, director of the MS Comprehensive Care Center at NYU Langone in New York City.

Multiple sclerosis (MS) is a neurological disorder that usually appears between the ages of 20 and 40. It is caused by the immune system mistakenly attacking the body's own myelin (the protective coating surrounding nerve fibers in the spine and brain). Depending on where the damage occurs, symptoms include vision problems, muscle weakness, numbness, and difficulty with balance and coordination.

Most people with MS have the relapsing-remitting form, in which symptoms flare for a period and then ease. Over time, the disease becomes more progressive.

Immune system cells called B cells appear to play a particularly important role in the development of MS. In recent years, monoclonal antibodies have been developed that remove B cells from the blood. One of these, called ocrelizumab (Ocrevus), was approved in the United States in 2017. A second drug, ofatumumab (Kesimpta), was approved in 2020.

Both antibodies destroy B cells by attacking a protein on the cells called CD20. Ublituximab has the same target, but is designed to be more potent at eliminating B cells, said Dr. Lawrence Steinman, a senior investigator on the new trial.

The trial did not compare ublituximab to any of the existing anti-CD20 antibodies, said Steinman, a professor of neurology at Stanford University. So it's not known whether it's more or less effective.

But one potential advantage of the new antibody, Steinman said, is that it can be administered quickly.

Both Ocrevus and ublituximab require patients to visit a medical center for infusions every six months. However, an Ocrevus infusion takes about three hours, while ublituximab can be administered in one hour.

Meanwhile, Kesimpta completely avoids infusions. It is taken at home once a month, using an autoinjector.

“There are different solutions for different people,” Steinman said. “I think it's always good to have options.”

The findings, published August 25 in the journal New England Journal of Medicineare based on more than 1,000 patients with MS, mostly relapsing-remitting MS. A small percentage had secondary progressive MS, a second phase of the disease that follows years of relapses and remissions.

About half were randomly assigned to ublituximab infusions, while the other half took the oral drug Aubagio (teriflunomide).

Over 96 weeks, patients receiving ublituximab were half as likely to relapse (with an average annual rate of just under 0.1, versus nearly 0.2 among Aubagio patients). And on MRI scans, they showed fewer areas of inflammation in the brain.

B cells are responsible for producing antibodies that fight infections. So one of the main safety concerns with decreasing B cells is that it can leave people more vulnerable to infections. That was the case in this trial: 5% of ublituximab patients developed a serious infection, including pneumonia, versus 3% of Aubagio patients.

There are many drugs approved to treat MS, but Krupp said some recent studies show that patients do better long-term when they receive “high-efficacy” drugs (which include anti-CD20 antibodies) compared with older drugs with more moderate effects.

For Steinman, the sooner highly effective treatment can be started, the better.

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“My philosophy is that if the insurance covers it, the disease must be stopped quickly and decisively,” he said.

This raises the real issue of cost: CD20 monoclonal antibodies are expensive; the current list price for Ocrevus is about $68,000 per year, according to drugmaker Genentech.

Too often, Krupp and Steinman said, medication decisions depend on which ones are covered by a patient's insurance plan.

More information

The National Multiple Sclerosis Society has more information on MS treatment.

SOURCES: Lawrence Steinman, MD, director and professor of neurology and neurological sciences and pediatrics, Beckman Center for Molecular Medicine, Stanford University, Stanford, California; Lauren Krupp, MD, director, NYU Langone Multiple Sclerosis Comprehensive Care Center, and professor of pediatric neuropsychiatry, NYU Grossman School of Medicine, New York City; New England Journal of MedicineAugust 25, 2022

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