Novartis Secures FDA Approval for Oral BTK Inhibitor Rhapsido in Chronic Hives Treatment

Novartis has achieved a significant milestone with the U.S. Food and Drug Administration (FDA) approval of Rhapsido (remibrutinib), the first oral Bruton's tyrosine kinase (BTK) inhibitor for the treatment of chronic spontaneous urticaria (CSU), also known as chronic hives. This approval marks a new era in the management of CSU, offering patients a more convenient alternative to existing injectable therapies.

A Novel Approach to Chronic Hives Management

Rhapsido is indicated for adult patients who continue to experience symptoms of hives despite antihistamine treatment. This oral medication targets the BTK enzyme, disrupting the signaling cascade responsible for histamine release, which causes the characteristic itching and swelling associated with CSU.

The approval is based on compelling data from the Phase III REMIX clinical program. Published in the New England Journal of Medicine, the study demonstrated significant improvements in urticaria activity scores compared to placebo, with benefits sustained through 24 weeks of follow-up.

Dr. Giselle Mosnaim, an immunologist at the University of Chicago and investigator on the REMIX trial, highlighted the significance of this approval, stating, "Rhapsido provides an alternative beyond existing injectable treatments and gives patients an oral option that can easily be incorporated into their daily lives."

Market Impact and Accessibility

Novartis estimates that Rhapsido could benefit more than half of the 1.7 million people with CSU in the United States who do not respond completely to antihistamines. The company has announced that Rhapsido will be available "in the coming days" with a wholesale acquisition cost of $4,521 per 30-day supply.

Victor Bulto, Novartis' U.S. president, emphasized the potential market, noting that out of approximately 400,000 target CSU patients in the U.S., only about 20% are currently being treated with existing options like Xolair or Dupixent. This leaves substantial room for Rhapsido's adoption.

Expanding Horizons: Beyond CSU

Novartis is not limiting Rhapsido to CSU treatment. The company is actively exploring its potential in other immune-mediated conditions:

1. Hidradenitis suppurativa: A Phase IIb study showed promising results, with plans for potential approval filing.
2. Multiple sclerosis: Two Phase III studies are underway, with primary completion expected in 2026.
3. Food allergies: Recent Phase II trials have shown promise, potentially positioning Rhapsido as the first oral allergen-agnostic treatment.
4. Other indications: Novartis is pushing Rhapsido into Phase III studies for chronic inducible urticaria and generalized myasthenia gravis.

These developments underscore Novartis' commitment to expanding its immunology portfolio, particularly as its blockbuster drug Cosentyx approaches patent expiration towards the end of the decade.

As the pharmaceutical landscape evolves, Rhapsido's approval not only represents a significant advancement in CSU treatment but also signals the start of potential competition in the BTK inhibitor space for immunological indications, with companies like Sanofi also making strides in this area.