Figitumumab (CP-751871) is a potent and fully human monoclonal anti-insulin-like growth factor 1 receptor (IGF1R) antibody. Figitumumab prevents IGF1 from binding to IGF1R with an IC50 of 1.8 nM[1].
Figitumumab (CP-751871) (152 pM-10 μM; 3 days) inhibits cancer cell proliferation[1].
Figitumumab (1 μg/mL; 1 min or 24 h) induces the down-regulation of IGF-1R[2].
Figitumumab inhibits IGF1-induced autophosphorylation of IGF1R with an IC50 of 0.42 nM, and indirectly inhibits AKT activation[2].
Figitumumab recognizes the IGF-1R/IR heterodimer complex[2].
Cell Proliferation Assay[1]
| Cell Line: | Breast, colon, lung small cell, and non-small cell cancer lines |
| Concentration: | 152 pM-10 μM |
| Incubation Time: | 3 days |
| Result: | 15 cell lines (NCIH441, NCIH526, SW403, CACO2, SW48, NCIH524, SKCO1, SNUC1, LS1034, COLO205, MDAMB361, NCIH508, LS513, MCF7, NCIH378) were highly sensitive to the drug at IC50 values ≦ 100 nM. |
Western Blot Analysis[2]
| Cell Line: | 3T3/IGF-1R cell |
| Concentration: | 1 μg/mL |
| Incubation Time: | 1 min or 24 h |
| Result: | Blocked IGF-I- or IGF-II-induced autophosphorylation of the IGF-1R. |
Figitumumab (CP-751871) (31-125 μg/mouse; i.p.; once) induces the down-regulation of tumor associated IGF-1R in mice[2].
Figitumumab (62.5-500 μg/mouse; i.p.; once) inhibits the growth of s.c. xenografts derived from colon (Colo-205), breast (MCF7), and lung (H460) cancer cell lines in mice[2].
| Animal Model: | Female atmic mice (CD-1 nu/nu) bearing NIH3T3/IGF-1R tumors[2] |
| Dosage: | 31 to 125 μg per mouse |
| Administration: | Intraperitoneal injection, once |
| Result: | Resulted in a serum Cmax between 12 and 24 hours. At 24 hours, there was a dose-dependent reduction of IGF-1R protein in tumors, with 50% reduction observed at a serum concentration of 15 μg/mL. Resulted in a down-regulation of IGF-1R from the tumor. The half-life in an atmic mouse was determined to be 4 to 6 days by longer-term studies. |
| Animal Model: | Female atmic mice (CD-1 nu/nu), human Colo-205 tumor xenograft model[2] |
| Dosage: | 62.5 μg or 250 μg per mouse |
| Administration: | Intraperitoneal injection, once |
| Result: | Inhibited the tumor growth. |
[1]. Pavlicek A, et al. Molecular predictors of sensitivity to the insulin-like growth factor 1 receptor inhibitor Figitumumab (CP-751,871). Mol Cancer Ther. 2013 Dec;12(12):2929-39.
[2]. Cohen BD, et al. Combination therapy enhances the inhibition of tumor growth with the fully human anti-type 1 insulin-like growth factor receptor monoclonal antibody CP-751,871. Clin Cancer Res. 2005 Mar 1;11(5):2063-73.