Figure 7. Schematic activity map of BKM120 and BKM120 derivatives and dosing schemes.

(a) BKM120 targets PI3K and tubulin proportionally. A concentration increase of BKM120 does therefore not change PI3K/tubulin targeting ratios, while combinations of selective PI3K inhibitors (such as PQR309) and potent microtubule-targeting drugs (MTDs) allow a flexible access to PI3K inhibition and perturbation of microtubule dynamics. (b) PI3K inhibitors are typically administered daily (dosing schedule in green), while microtubule targeting drugs are usually given in 1–3 week intervals (dosing schedule in red) for a limited time only.