Envudeucitinib, a Potent, Next-Generation, Allosteric Inhibitor of TYK2: A Narrative Review

Area of Science:

• Immunology
• Dermatology
• Pharmacology

Background:

• Psoriasis is a prevalent immune-mediated inflammatory disease (IMID) affecting millions globally, often undertreated by existing therapies due to limited efficacy and safety concerns.
• Tyrosine kinase 2 (TYK2) is a validated target in psoriasis, mediating key inflammatory cytokine signaling pathways, including IL-23, IL-17, IL-12, and type I interferons (IFNs).
• Selective TYK2 inhibition offers targeted immunomodulation compared to broader immunosuppression from JAK 1/2/3 inhibitors, potentially improving safety and efficacy.

Purpose of the Study:

• To evaluate the efficacy and safety of envudeucitinib, a next-generation oral allosteric TYK2 inhibitor, for treating moderate-to-severe plaque psoriasis.
• To assess the pharmacokinetic and pharmacodynamic profile of envudeucitinib, including its sustained target engagement and impact on inflammatory biomarkers.
• To investigate the potential of envudeucitinib as a targeted therapy for psoriasis and other IMIDs.

Main Methods:

• Preclinical and Phase 1 studies assessed envudeucitinib's mechanism of action, pharmacokinetics, and pharmacodynamics, including TYK2 inhibition and effects on type I IFN gene signatures.
• A Phase 2 study evaluated envudeucitinib in adults with moderate-to-severe plaque psoriasis, assessing efficacy responses and safety profiles at various doses.
• Ongoing Phase 3 ONWARD studies are further investigating the efficacy and safety of envudeucitinib in larger patient populations.

Main Results:

• Envudeucitinib demonstrated maximal TYK2 inhibition (IC90) over 24 hours with twice-daily oral administration in Phase 1 studies, indicating sustained target engagement.
• The drug reduced type I IFN gene signatures in whole blood and pSTAT1 in T cells, confirming target engagement.
• In Phase 2 studies, envudeucitinib showed dose-dependent maximal TYK2 inhibition and significant, increasing efficacy responses through 52 weeks with a favorable safety profile.

Conclusions:

• Envudeucitinib is a selective oral allosteric TYK2 inhibitor with a favorable pharmacokinetic/pharmacodynamic profile, demonstrating sustained target engagement and promising efficacy in moderate-to-severe plaque psoriasis.
• The drug's targeted mechanism avoids adverse events associated with broader JAK inhibition, offering a potentially safer treatment option.
• Further evaluation in Phase 3 studies is warranted to confirm the long-term efficacy and safety of envudeucitinib for psoriasis treatment.