The lead compound to delgocitinib was tofacitinib, a potent pan-JAK inhibitor. To maintain the overall pan-JAK inhibition profile of tofacitinib, the pyrrolopyrimidine hinge binder, and the cyanoacetyl group were kept fixed. At the same time, the central aminopiperidine linker was replaced by a variety of spirocyclic scaffolds to maintain comparable binding patterns. This effort identified the three-dimensional diazaspiro[3.4]octane scaffold as the optimal linker, and further SAR studies led to delgocitinib, which demonstrates better selectivity against JAK3 compared to tofacitinib and its selectivity for the JAK family over LCK is also improved. Delgocitinib exhibits no significant inhibition of non-JAK kinases under 1 μM except ROCK2.
Clinical Use
Delgocitinib is a pan-JAK inhibitor that inhibits all Janus Kinase (JAK) family members. Topical delgocitinib 0.5% ointment received its first approval in Japan in 2020 for treating adults with atopic dermatitis. The FDA has granted delgocitinib cream fast-track designation for chronic hand eczema.
