Sonelokimab

Psoriatic arthritis (PsA) is a progressive, inflammatory and multidomain disease characterized by damage across heterogeneous tissues, including skin, articular and extra-articular manifestations. IL-17A and IL-17F are isoforms in the IL-17 cytokine family that are overexpressed across multiple tissues in PsA and form pro-inflammatory homodimers and heterodimers. While IL-17A is more potent and was the initial target of therapeutic interventions in PsA, IL-17F is preferentially elevated in psoriatic tissues, suggesting that inhibiting both IL-17A and IL-17F may be critical to exerting optimal therapeutic effects. Sonelokimab (SLK) is a nanobody consisting of three VHH domains that mediate binding of IL-17A, IL-17F and albumin. This design allows SLK to bind with a similarly high affinity to both IL-17A and IL-17F, blocking signaling through all IL-17A and IL-17F dimer combinations. The third albumin-binding domain increases half-life and targets albumin-rich sites of chronic inflammation and edema.