TST005

P1, N=19, Terminated, Suzhou Transcenta Therapeutics Co., Ltd. | N=55 --> 19 | Trial completion date: Dec 2023 --> Sep 2023 | Active, not recruiting --> Terminated | Trial primary completion date: Dec 2023 --> Sep 2023; Corporate Decision

Here we report TST005 anti-tumor activities in MC38 colorectal cancer and EMT-6 breast cancer models compared to M7824 (Merck’s PD-L1/TGF-βRII) analog and its safety profiles following single or repeated doses in rats and non-human primates (NHP). Based on the exposure of TST005 in monkeys and predicted exposure at First in Human (FIH) dose, the safety margin of TST005 will be higher than 200 and 500 folds calculated on Cmax and AUC respectively. In conclusion, we have demonstrated the antitumor activity of TST005 in PD/PD-L1 sensitive and resistant tumor models as well as the safety profile in NHP, TST005 has been granted for phase 1 clinical trials in USA (NCT04958434).

In conclusion, we have demonstrated that TST005 has enhanced immunomodulatory properties and can induce potent antitumor activity in preclinical tumor models that are not sensitive to PD-1/PD-L1 monotherapy. These results provide the rationale for further clinical evaluation of TST005 in patients with advanced solid tumors and less optimal response to first generation PD(L)-1 based immunotherapy.