S3I-201 shows potent inhibition of STAT3 DNA-binding activity with IC50 of 86 μM, and low activity towards STAT1 and STAT5.

Stattic, a nonpeptidic small molecule, potently inhibits STAT3 activation and nuclear translocation with IC50 of 5.1 μM in cell-free assays, highly selectivity over STAT1.

Niclosamide can inhibit DNA replication and inhibit STAT3 with IC50 of 0.7 μM in a cell-free assay. Niclosamide selectively inhibits the phosphorylation of STAT3 and has no obvious inhibition against the activation of other homologues (e.g., STAT1 and STAT5). It is also an antiparasitic agent. It induced apoptosis by activating the intrinsic and caspase-independent pathway in human A549 and CL1-5 cells.

C188-9 is a STAT3 inhibitor and has no effects on non-alcoholic steatohepatitis (NASH) and hepatocellular carcinoma (HCC) in mice.

BP-1-102 is an orally available, small-molecule inhibitor of transcription factor STAT3.

SH-4-54 is a potent, small molecule, nonphosphorylated STAT3 inhibitor with KD of 300 nM and 464 nM for STAT3 and STAT5, respectively.

Cryptotanshinone is a potent STAT3 inhibitor (IC50 =4.6 μM) and inhibits STAT3 Tyr705 phosphorylation in DU145 prostate cancer cells. Cryptotanshinone showed inhibitory effect on PL(pro) with IC50 value of 0.8μM and slight inhibitory effect on 3CLpro with IC50 value of 226.7μM.

HJC0152 inhibits STAT3 promoter activity in MDA-MB-231 cells in a dose-dependent manner.

STA-21 is a selective STAT3 inhibitor.

Napabucasin is a first-in-class cancer stemness inhibitor that targets STAT3.

HO-3867 selectively inhibits the phosphorylation and transcription of STAT3. It is an analog of curcumin.

Artesunate is a part of the artemisinin group of agents with an IC50 of < 5 μM for small cell lung carcinoma cell line H69. It is a potential inhibitor of STAT-3 and EXP1 and exhibits selective cytotoxicity of cancer cells over normal cells in vitro.

SH5-07 is an inhibitor of STAT3 with IC50 of 3.9±0.6 μM with antitumor effects and it can suppresse human glioma and breast cancer.