CDK4 and neoplasm: However, when the CDK4/6 inhibitor–based regimens were given together with customized additional drugs matched to genomic co-alterations in that patient’s tumor (resulting in a high matching score (≥50%), overall longer PFS was observed when compared with that of patients who were treated with a CDK4/6-matched regimen with a low matching score (<50%) (PFS 6.2 vs. 2.0 months, P < 0.001 [P values were calculated after multivariate analysis]) (Table 2).