Atezolizumab是一种人源化单克隆抗体IgG1，抵抗程序性死亡因子配体1(PD-L1)，用于癌症研究。
CAS：1380723-44-3
分子量：144590.5
纯度：98%
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Background:

Biological Activity
In vitro: A key feature of atezolizumab is that it is FcγR-binding deficient, so it cannot bind to Fc receptors on phagocytes and therefore does not cause antibody-dependent cell-mediated cytotoxicity (ADCC). atezolizumab treatment could bring cytokine changes include transient increases in IL-18, IFNγ, and CXCL11, and a transient decrease in IL-6; cellular changes include increases in proliferating CD8+ T cells.
In vivo: By blocking the PD-L1/PD-1 immune checkpoint, atezolizumab reduces immunosuppressive signals found within the tumor microenvironement and consequently increases T cell mediated immunity against the tumor. The pharmacokinetics of atezolizumab were initially studied in cynomolgus monkeys and mice where its volume of distribution was calculated to be approximately that of the plasma volume. The in vivo biodistribution of atezolizumab 24 hours after infusion is, in order of magnitude, the spleen, lungs, kidneys, liver, heart, and muscle. In tumor bearing animals, the drug also accumulates intratumorally, initially at the pushing border of the tumor and progressing later to the tumor core, particularly if the tumor is necrotic. The pharmacokinetic curve of atezolizumab is dose-dependent (non-linear) because of target mediated drug disposition (binding of drug to the PD-L1 ligand in the body). Saturation of PD-L1 receptors by atezolizumab on circulating CD4 and CD8 T cells occurs between 24 and 48 hours after dosing with serum concentrations > 0.5 μg/mL. MPDL3280A binds to PD-L1 in monkey and human with comparable affinity between species.

参考文献
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Lesniak WG, et al. Bioconjug Chem. 2016 Sep 21;27(9):2103-10. PMID: 27458027.
[2].Atezolizumab versus docetaxel for patients with previously treated non-small-cell lung cancer (POPLAR): a multicentre, open-label, phase 2 randomised controlled trial.
Fehrenbacher L, et al. Lancet. 2016 Apr 30;387(10030):1837-46. PMID: 26970723.