pf-4989216

PF-4989216 is a **novel orally available small molecule inhibitor** that selectively targets phosphoinositide 3-kinase (PI3K) isoforms with potent activity against p110α and p110δ catalytic subunits (IC50: 2 nM for p110α, 1 nM for p110δ), and less potency for p110β, p110γ, and VPS34[1][3][5][7]. It was developed for oncology indications, especially **small-cell lung cancer (SCLC)** harboring activating mutations in the gene PIK3CA, where it demonstrated preclinical antitumor efficacy via inhibition of PI3K signaling, reduction of cell proliferation, blockade of cell-cycle progression, and induction of BIM-mediated apoptosis[1][2][3][4][5][7]. In SCLC with PTEN loss, it inhibited PI3K signaling but did not significantly induce apoptosis or affect viability[2][3]. PF-4989216 is not approved for clinical use and remains in **preclinical development**[3][7]. It is associated with resistance mediated by ABCG2 (an efflux pump), which may reduce its intracellular accumulation and effectiveness[5].

Brand names

PF-4989216PF4989216PF 4989216

Other names

PF-4989216PF4989216PF 4989216