Pediatric Patients With Myasthenia Gravis Need More Treatment Options: Jonathan Strober, MD

Nipocalimab (Imaavy; Johnson & Johnson) was approved by the FDA on April 30, 2025, to treat generalized myasthenia gravis in adult patients and pediatric patients 12 years or older who are anti–acetylcholine receptor (AChR) positive or anti–muscle-specific kinase (MuSK) antibody positive, based on data from the phase 3 Vivacity-MG3 study (NCT04951622). This is the first and only FcRn-blocking monoclonal antibody approved to treat these 2 patient populations. The therapy received a priority review designation in January for patients who were anti–AChR, –MuSK, or –LRP4 positive.

Earlier this year, nipocalimab data from Vivacity-MG3 supported the medication's long-term use in generalized myasthenia gravis when it is added to standard-of-care therapies. In particular, the patients randomized to nipocalimab saw larger reductions in their Myasthenia Gravis Activities of Daily Living scores and median immunoglobulin G levels.

In this interview with This American Journal of Managed Care®, Jonathan Strober, MD, pediatric neurologist and an investigator on the phase 2/3 Vibrance-MG study (NCT05265273), being conducted in an exclusively pediatric population, speaks to the significance of this approval for the pediatric patients who are living with the debilitating neuromuscular disorder. Strober is also director of clinical services for child neurology and director of the Muscular Dystrophy Clinic at UCSF Benioff Children's Hospital.

This transcript has been edited for clarity; captions were auto-generated.

Transcript

Why is this approval especially significant for pediatric patients with myasthenia gravis?

The approval of nipocalimab for pediatric patients is so important because we really don't have many drugs that are approved in the pediatric age group, and when we try to treat our patients who are having difficulties with the other medications that are available that actually don't have approval for myasthenia gravis, even in adults, it's just stuff that we've used over the years. The insurance companies often deny because it's only approved for, say, 16 [years] and over or 18 [years] and over, and so we have a hard time getting the drugs that could benefit our patients to our patients because of insurance issues. Getting this approval will help us get approval for these patients who desperately need these medications.

What is the current standard of care for pediatric myasthenia gravis, and what treatment gaps does this approval help to fill?

The current standard of care for myasthenia gravis, especially in the pediatric age group, starts with a medication called Mestinon [pyridostigimine; Bausch Health], which has been around forever and used in myasthenia—although it's just a very symptomatic treatment. It only lasts a couple of hours, [and] it's not getting to the problem that's causing the symptoms.

The antibodies, which attack the receptors on the muscle and cause them to break down and block them, that's why you get progressive weakness in these patients, and so the immunologic treatments are what we then use: prednisone steroids [have] been around also for a very long time and, of course, has a ton of side effects, especially for our growing youth, but it's something that we can start with, but we want to get them off to prevent long-term complications.

In the past, we used a lot of the immunologic medications that kind of attack all of the immune system, all the types of cells, [and] all the secondary effects of immune reaction. It really is, I'd say, a heavy hitter, and, again, when you're really attacking the immune system that way. These are chemotherapy drugs, drugs that are used for cancer, [and] drugs that are used for rejection after a patient receives a donated organ.

The newer medications that are coming out, and a lot of them are approved, are much more focused on the problem. Like in this case, [with] nipocalimab, we're reducing antibody levels, which are the biggest problem, and something we've tried to do other ways, but again, kind of involving a lot more of the immune system.