NEW YORK – Telix Pharmaceuticals on Tuesday said it has treated the first patient with its targeted radiation therapy TLX250 (177Lu-DOTA-girentuximab) in combination with Merck KGaA's DNA-dependent protein kinase inhibitor peposertib in a Phase I study.
The Phase Ib study, called STARSTRUCK, includes patients with solid tumors expressing carbonic-anhydrase IX (CAIX). Researchers will enroll up to 80 patients in the trial and evaluate three dose levels of the TLX250-peposertib combination.
Once a dose has been established, Telix will enroll two cohorts of patients: an all-comers group of clear-cell renal cell carcinoma patients and another group of CAIX-positive solid tumor patients, excluding those with renal cell carcinoma.
TLX250 delivers targeted radiation therapy to cells expressing CAIX, an antigen found on the surface of clear-cell renal cell carcinoma cells, and induces DNA damage in those cells. Telix and Merck KGaA have conducted preclinical studies that suggest that TLX250 in combination with peposertib may prevent the cells from repairing this damage.
"Preclinical data has shown excellent combination response [with TLX250 and peposertib], which has potential to translate to additional response or more tolerable treatment regimens in patients," Telix Chief Medical Officer Colin Hayward said in a statement.
Telix, based in Melbourne, Australia, is also studying TLX250 in combination with Bristol Myers Squibb's Opdivo (nivolumab) in a Phase II trial in clear-cell renal cell carcinoma patients and in another Phase II trial in combination with Opdivo and Exelixis' Cabometyx (cabozantinib) as a first-line treatment for clear-cell renal cell carcinoma.
The firm is also developing a PET imaging agent, TLX250-CDx, to diagnose kidney, triple-negative breast, and other cancers. Last year, the firm said it would seek approval for TLX250-CDx in clear-cell renal cell carcinoma in the US and in other markets.