The chemical structure that was submitted to the WHO for the INN lorpucitinib is identical to the structure of example 1 that is claimed as a pan-Janus kinase inhibitor in Janssen's patent WO2018112379A1 [1
]. Based on structural conformation this is an exact match to PubChem SID 395564298
, and this is associated to CID 134611548
. However, this CID does not specify the stereochemical conformation as described in the patent or as stipulated in the INN submission. The chemical structure was disclosed in March 2020 as a JAK inhibitor that is intended for the treatment of inflammatory bowel disease [2
]. Its activity is restricted to the gut by virtue of its permeability and physicochemical properties, and this limits systemic exposure and the potential for on-target adverse events.