Long-term Kesimpta Use Not Seen in Trial to Depress Antibody Levels

Long-term use of Kesimpta (ofatumumab) among people with multiple sclerosis (MS) did not substantially lower their antibody levels, allowing them to retain an ability to fight infections, new data from a Phase 3 clinical trial indicate.

“These long-term results continue to support Kesimpta as a high-efficacy, first-choice treatment with a favorable safety profile for people living with [relapsing MS],” Marcia Kayath, global head medical affairs at Novartis Pharmaceuticals, which markets Kesimpta, said in a press release.

Kesimpta is approved in the U.S. and European Union (EU) to treat relapsing forms of MS, including clinically isolated syndrome (CIS), relapsing-remitting MS (RRMS), and active secondary progressive MS (SPMS). The medication works by targeting the CD20 protein to kill a type of immune cell called B-cells.

B-cells are involved in the inflammation that drives disease progression in MS; however, these cells are also critical for defending the body against viruses and other disease-causing invaders. Their main role in fighting infections is to produce antibodies.

Antibodies — also called immunoglobulins — are immune proteins that bind to specific disease-associated molecular targets (like a virus), activating the immune system to destroy the treat.

There are several types of immunoglobulins with specific roles in immunity. Of particular note, immunoglobulin M (IgM) is the first type of antibody produced by B-cells in response to a threat, and immunoglobulin G (IgG) is the most abundant type of antibody that drives an immune response against an infection.

“Evidence shows that low immunoglobulin levels have been linked to an increased risk of infection, which is why testing of these levels is recommended for people living with MS prior to taking any anti-CD20 treatment,” said Heinz Wiendl, MD, director of the Clinic of Neurology at University Hospital Münster in Germany.

At the recent Congress of the European Academy of Neurology meeting, researchers presented new data from the ALITHIOS Phase 3 extension clinical trial (NCT03650114).

This Novartis-sponsored study is collecting long-term safety and efficacy data on adults who participated in previous Kesimpta clinical trials, such as the ASCLEPIOS Phase 3 trials (NCT02792218 and NCT02792231) that served as the basis for the therapy’s U.S. and EU approval.

ALITHIOS has enrolled 1,703 participants. At the time of the present analysis, 456 of them had been treated with Kesimpta for at least 3.5 years.

Analysis results showed that patients’ IgG levels remained unchanged after 3.5 years of treatment, while IgM levels remained within the reference range.

Additional analyses showed no association between low immunoglobulin levels and the risk of serious infections. The overall risk of infections among participants on Kesimpta was low, and the findings overall were consistent with prior results from ASCLEPIOS, according to Novartis.

“It’s encouraging to see that over a long period of time, IgG levels remained stable and IgM levels remained well within the reference ranges in all groups treated with ofatumumab, with no increased risk of infections,” Wiendl said.

“Preservation of immunoglobulin levels is important to fight infections, like COVID-19, so we’re very happy to share long-term data showing Kesimpta had unchanged IgG levels, providing physicians with important information relevant to the long-term benefit/risk of treating with Kesimpta,” Kayath added.

Of note, antibody-driven immune responses are a key component of what makes vaccines work, including the vaccines for COVID-19. Research into how treatment with Kesimpta may affect the effectiveness of these vaccines is ongoing.