The overall increase in PNP Clinical compounds (Figure ) is evident in heavily pursued targets that have seen long-term production of Clinical compounds. For the epidermal growth factor receptor-1 (EGFR-1) kinase (Figure ), the invention of the 45 Clinical compounds found in ChEMBL has spanned 30 years. The first drug to the market, gefinitib, is not a PNP but contains 2 NP fragments, one of which, 4-anilinopyrimidine, provided for further development of the class, leading to approved PNPs such as lapatinib, followed later by brigatinib and osimertinib, which both contain a 2-anilinopyrimidine NP fragment (Figure ). PNPs have been the dominant class of EGFR Clinical compounds since 2005, with their occurrence exceeding that seen in Reference compounds (Figure ). Vascular endothelial growth factor receptor 2 (VEGF-2) kinase, with 54 Clinical candidates over 26 years, shows a similar increase In PNP Clinical compounds over time (Figure ). comparable pharmacophoric features, a tendency that can also lead to promulgation of the same