Telix has announced that the first patient has been dosed in a Phase 1 study of its investigational targeted radiation therapy, TLX250, combined with Merck's DNA-dependent protein kinase (DNA-PK) inhibitor candidate, peposertib (M3814).
The study is in patients with solid tumours expressing the potential pan-cancer target, carbonic-anhydrase IX (CAIX).
The STARSTRUCK trial is an open-label, single-arm, multicentre dose escalation and dose expansion study to evaluate the safety profile, dosing and activity of TLX250 in combination with peposertib.
The target population is patients with CAIX-expressing solid tumours that are relapsed or refractory to standard therapies. Up to 80 patients will be assessed in this study in Australian sites.
Telix said the clinical hypothesis is that the combination of TLX250 and a DNA-PK inhibitor enhances potency through their synergistic action on cancer cells.
Targeted radiation effectively induces DNA damage in targeted cancer cells and the DNA-PK inhibitor may act to prevent the cell from repairing this damage, resulting in higher potency at lower doses.
"This hypothesis was confirmed in preclinical studies, conducted under a strategic research collaboration between Merck and Telix announced in 2019," said the company, adding that it provided evidence that the combined effect of peposertib and TLX250 has the potential to significantly improve efficacy and reduce the required radiation dose for tumour reduction and remission, compared to targeted radiation alone.
Telix chief medical officer Dr Colin Hayward said, "Preclinical data has shown excellent combination response, which has potential to translate to additional response or more tolerable treatment regimens in patients."