On March 25, 2020, the U.S. Food and Drug Administration (FDA) approved a new Class 1 drug—Zeposia (ozanimod)—for the treatment of relapsing multiple sclerosis.

Zeposia (ozanimod), developed by Celgene, is the first new drug approved by the U.S. FDA since Bristol-Myers Squibb completed its acquisition of Celgene. Zeposia is available as a standard capsule in strengths of 0.23 mg, 0.46 mg, and 0.92 mg. The dosing regimen involves taking 0.23 mg orally for days 1–4, 0.46 mg orally for days 5–7, and 0.92 mg orally starting on day 8, all taken once daily. Clinical indications include clinically isolated syndrome, relapsing-remitting disease, and active secondary progressive disease. Ozanimod exhibits high oral bioavailability, with a Tmax of approximately 6–8 hours post-oral administration and a mean elimination half-life of 21 hours.

Ozanimod is a sphingosine-1-phosphate (S1P) receptor modulator with high affinity for S1P receptor subtypes 1 (S1P1) and 5 (S1P5). It inhibits lymphocyte efflux from lymph nodes, thereby reducing peripheral blood lymphocyte counts. The mechanism of action of ozanimod in multiple sclerosis remains unclear but may be associated with reduced lymphocyte migration into the central nervous system.

Multiple sclerosis (MS) is a demyelinating neurological disorder in which the protective insulation (myelin sheath) surrounding nerve cells in the brain or spinal cord is damaged. This impairs signal transmission within the nervous system, leading to symptoms such as double vision, unilateral vision loss, muscle weakness, sensory numbness, or coordination difficulties. The course of MS is highly variable, with symptoms potentially recurring or progressively worsening. Between episodes, symptoms may resolve completely, yet permanent neurological damage persists—particularly evident in severe cases. MS predominantly affects young and middle-aged adults, with a higher prevalence in women than men. In 2017, approximately 1.6 to 1.95 million people worldwide were affected (about 30 per 100,000 population), with an estimated 18,000 annual deaths. In China, multiple sclerosis is classified as a rare disease, with an incidence rate of approximately 1.5–3.2 per 100,000, and an estimated patient population exceeding 30,000.

The FDA has currently approved several medications for treating MS, as shown in the table below:

Dimethyl fumarate

Currently, the primary global dosage forms are enteric-coated capsules and sustained-release capsules. Biogen's dimethyl fumarate enteric-coated capsules generated global sales of $4.433 billion in 2019, exhibiting a gradual upward trend from 2015 to 2019. Currently, this product has not been approved for import, and no domestic manufacturers hold approval documents. Nine manufacturers have submitted applications for enteric-coated capsules, while one manufacturer has applied for sustained-release capsules.

Dimethyl fumarate

Currently, the primary global dosage forms are enteric-coated capsules and sustained-release capsules. Biogen's dimethyl fumarate enteric-coated capsules generated global sales of $4.433 billion in 2019, exhibiting a gradual upward trend from 2015 to 2019. Currently, this product has not been approved for import, and no domestic manufacturers hold approval documents. Nine manufacturers have submitted applications for enteric-coated capsules, while one manufacturer has applied for sustained-release capsules.

Fingolimod Hydrochloride

In August 2018, fingolimod hydrochloride oral capsules were included in the first batch of urgently needed new drugs already marketed overseas by the Center for Drug Evaluation. By July 2019, Novartis' fingolimod hydrochloride capsules (Gilenya®) had been approved for import into China, demonstrating remarkably swift regulatory review. Novartis's fingolimod hydrochloride capsules generated global sales of $3.223 billion in 2019, representing a 3.5% year-on-year decline. The substance patent for this product expired in February 2019. Ten domestic manufacturers have submitted applications for the capsule formulation, while only one manufacturer has applied for the standard tablet formulation.

Teriflurid

The global sales of teriflunomide tablets produced by the originator manufacturer Sanofi reached approximately $2 billion in 2019, remaining largely unchanged from 2018. The product was approved for import in July 2018, with nine domestic companies having submitted applications for tablet formulations. Currently, only the product patent for the originator drug remains unexpired.

In May 2018, five government departments—the National Health Commission, Ministry of Science and Technology, Ministry of Industry and Information Technology, National Medical Products Administration, and National Administration of Traditional Chinese Medicine—jointly released the first catalog of rare diseases. In February 2019, the National Health Commission issued the “Guidelines for Diagnosis and Treatment of Rare Diseases (2019 Edition).” With increasing national emphasis on rare diseases and supportive policies, domestic companies have increasingly turned their attention to this field. Multiple sclerosis, with its global market valued at 24 billion, has naturally become a key focus for pharmaceutical R&D. It is predicted that competition among domestically produced drugs for multiple sclerosis will intensify significantly in the near future.