First Multiple Sclerosis Biosimilar Approved

— Natalizumab-sztn gets a nod from the FDA

FDA APPROVED natalizumab-sztn (Tyruko) over a computer rendering of a damaged neuron.

The first biosimilar for multiple sclerosis (MS) was approved, the FDA announced late Thursday.

Natalizumab-sztn (Tyruko) was approved as a biosimilar to natalizumab (Tysabri) injection to treat clinically isolated syndrome, relapsing-remitting MS, and active secondary progressive MS, the agency said.

Like its reference biologic, natalizumab-sztn (previously called PB006) also was approved to treat certain adult patients with moderately to severely active Crohn's disease.

"Biosimilar medications offer additional effective treatment options that have the potential to increase access for people living with relapsing forms of multiple sclerosis," said Paul Lee, MD, PhD, of the FDA's Center for Drug Evaluation and Research. "Today's approval could have a meaningful impact for patients managing their disease."

The approval was based on evidence that showed no clinically meaningful differences in safety and effectiveness between the biosimilar and reference natalizumab. The treatment was evaluated in the phase III Antelope study.

Both natalizumab products carry a boxed warning about an increased risk of progressive multifocal leukoencephalopathy (PML), which can lead to death or severe disability. PML risk factors include the presence of anti-JC virus antibodies, longer therapy duration, and previous immunosuppressant use.

"These factors should be considered in the context of expected benefit when initiating and continuing treatment with natalizumab products, and healthcare providers should monitor patients and withhold treatment immediately at the first sign or symptom suggestive of PML," the FDA cautioned.

The PML risk means natalizumab products are available only through a restricted drug distribution program, under a risk evaluation and mitigation strategy (REMS). The program requires natalizumab prescribers and pharmacies to be certified and patients to be enrolled in the REMS. Prescribers must evaluate patients 3 and 6 months after the first infusion and every 6 months thereafter, as well as immediately and 6 months after stopping treatment.

Additional warnings include risks of herpes infections, thrombocytopenia, immunosuppression, or serious hypersensitivity reactions including anaphylaxis and hepatotoxicity, the FDA noted. Headache and fatigue are the most common side effects associated with natalizumab products. Arthralgia, urinary tract infection, lower respiratory tract infection, gastroenteritis, vaginitis, depression, pain in extremity, abdominal discomfort, diarrhea, or rash also can occur.

Natalizumab-sztn is the first biosimilar for MS, but several FDA-approved disease-modifying therapies (DMTs) have generics.

The National Multiple Sclerosis Society recently issued a position on biosimilars, noting that as "biosimilars are emerging within the DMT market, this can lead to an increase in access to affordable medicines, improve adherence, and help contain healthcare costs." The society also outlined roles for patients, providers, health plans, and others to take when incorporating biosimilar DMTs into MS care.

  • Judy George covers neurology and neuroscience news for MedPage Today, writing about brain aging, Alzheimer’s, dementia, MS, rare diseases, epilepsy, autism, headache, stroke, Parkinson’s, ALS, concussion, CTE, sleep, pain, and more. Follow