NTRK1 and Pruritus: oryzae (96% at 12.5 ppm).215 Almost at the same time, the compound was also identified from the culture broth of Nocardiopsis strain K-252a (named K-252a) as a potent inhibitor of protein kinase C (IC50 value of 32.9 nM).216,217 Subsequent studies revealed that the compound inhibits several other protein kinases.218,219 A PEGylated form of SF-2370 (K-252a), pagcantratinib (CT327) (250), was developed as inhibitor of tropomyosin-receptor kinase A (TrkA), which is associated with pruritus and psoriatic plaque formation.