Four PI3K inhibitors have also been FDA-approved (Figure 1): the two benzopyrimidinones idelalisib and duvelisib (PI3K δ and γ-selective) for three types of blood cancer hematologic malignancy or chronic lymphocytic leukemia, respectively [27,28] as well as the tricyclic heterocyclic copanlisib (PI3K α and δ-selective) for follicular lymphoma [29]. The gene discussed is PIK3CA; the disease is B-cell chronic lymphocytic leukemia.