Optimization of Novel Indazoles as Highly Potent and Selective Inhibitors of Phosphoinositide 3-Kinase Gamma for the Treatment of Respiratory Disease.
Down, K., Amour, A., Baldwin, I.R., Cooper, A.W.J., Deakin, A.M., Felton, L.M., Guntrip, S.B., Hardy, C., Harrison, Z.A., Jones, K.L., Jones, P., Keeling, S.E., Le, J., Livia, S., Lucas, F., Lunniss, C.J., Parr, N.J., Robinson, E., Rowland, P., Smith, S., Thomas, D.A., Vitulli, G., Washio, Y., Hamblin, J.N.(2015) J Med Chem 58: 7381
- PubMed: 26301626 
- DOI: https://doi.org/10.1021/acs.jmedchem.5b00767
- Primary Citation of Related Structures:  
5AE8, 5AE9 - PubMed Abstract: 
Optimization of lead compound 1, through extensive use of structure-based design and a focus on PI3Kδ potency, isoform selectivity, and inhaled PK properties, led to the discovery of clinical candidates 2 (GSK2269557) and 3 (GSK2292767) for the treatment of respiratory indications via inhalation. Compounds 2 and 3 are both highly selective for PI3Kδ over the closely related isoforms and are active in a disease relevant brown Norway rat acute OVA model of Th2-driven lung inflammation.
Organizational Affiliation: 
Refractory Respiratory Inflammation DPU, and ‡Allergic Inflammation DPU, Respiratory Therapeutic Area, GlaxoSmithKline R&D , Gunnels Wood Road, Stevenage, SG1 2NY, U.K.