Protagonist Therapeutics (PTGX) FDA announcement summary

Introduction and purpose

• ICOTYDE (icotrokinra) received US FDA approval for treating moderate-to-severe plaque psoriasis in adults and pediatric patients 12 years and older weighing at least 40 kg who are candidates for systemic therapy or phototherapy.

• ICOTYDE is the first and only targeted oral peptide that blocks the IL-23 receptor.

Details of approval or decision

• FDA approval was granted in March 2026 for ICOTYDE, formerly known as PN-235.

• Approval is based on four phase 3 studies that met all primary endpoints and demonstrated a favorable safety profile in 2,500 patients.

• ICOTYDE offers the convenience of a once-daily oral pill with efficacy comparable to injectable biologics.

Impact on industry and stakeholders

• ICOTYDE is positioned as a first-in-class oral IL-23R antagonist, potentially transforming the plaque psoriasis treatment landscape.

• Collaboration with Johnson & Johnson includes significant milestone and royalty payments, with up to $580M in future development and sales milestones and royalties up to 10% for annual sales over $4B.

• Additional indications and ongoing studies in psoriatic arthritis, ulcerative colitis, and Crohn's disease may further expand market potential.