In contrast to TNF inhibitors for psoriatic arthritis, which seem to peak and maintain response percentages, the DISCOVER-2 Trial (McInnes et al., PMID 34719872) suggests Il-23 inhibitors have a steady increase in response up to 2 years which makes it challenging to assess when a patient is failing therapy versus not yet responding. Is there a biologic explanation as to why Il-23 inhibitors may continue to have this gradual increase in response up to 2 years?