We’re excited to share new preclinical biodistribution and efficacy data for ¹³¹I-DualFAPi-5, our FAPi dimer lead candidate labeled with iodine-131, here shown head to head against its close radiometal analog, ¹⁷⁷Lu-DOTAGA-Glu(FAPi)2.
In this preclinical model, tumor uptake with ¹³¹I-DualFAPi-5 was approximately 3× higher, highlighting the strong potential of 1¹³¹I-DualFAPi-5 for effective FAP-targeted radioligand therapy, as well as adding additional support to the generally observed high tumor uptake with TetraKit Platform labeled compounds.
Moreover,¹³¹I-DualFAPi-5 showed promising and numerically higher tumor growth inhibition at a single dose of 30 MBq in this model, although this finding was not statistically significant. Notably, two mice remained tumor-free at the end of the study with ¹³¹I-DualFAPi-5, whereas no tumor-free mice were observed with the ¹⁷⁷Lu-based compound.
Importantly, iodine and astatine are directly interchangeable in this and other TetraKit compounds, suggesting that our astatine-labeled variant (²¹¹At-DualFAPi-5) could exhibit similarly promising in vivo behavior.
