Plinabulin(NPI-2358), a potent antimicrotubule, is a synthetic analog of NPI-2350. NPI-2358 binds to the colchicine-binding site of tubulin. NPI-2358 has potent in-vitro anti-tumor activity against various human tumor cell lines and maintains activity against tumor cell lines with various multidrug-resistant (MDR) profiles. NPI-2358 dose dependently increases HUVEC monolayer permeability--an in-vitro model of tumor vascular collapse. NPI-2358 in HUVECs was more potent than either colchicine or vincristine.
In vivo
At the RP2D of 30 mg/m?, plinabulin showed a favorable safety profile, while eliciting biological effects as evidenced by decreases in tumor blood flow, tumor pain, and other mechanistically relevant adverse events Plinabulin (7.5 mg/kg) significantly reduced the initial area under curve (IAUC) and the transfer constant (K(trans)) within 1 hour after injection. No significant anti-tumour effects were observed in the C3H tumours until doses of 12.5 mg/kg were achieved, but started at 1.5 mg/kg in the KHT sarcoma.