Seattle Genetics, a biotechnology company, has begun a Phase Ib trial of SGN-75 in combination with everolimus (afinitor) for patients with renal cell carcinoma (RCC).

Everolimus is an oral prescription medication used to treat advanced RCC in a condition where medicines, such as sunitinib or sorafenib, failed to work.

Seattle Genetics research and translational medicine senior vice president Jonathan Drachman said ADCs have the potential to change the way many types of cancer are treated, and the company is evaluating its ADC product candidate, SGN-75, in the Phase Ib trial for patients with CD70-expressing RCC.

"We are encouraged by the preliminary single-agent activity and tolerability demonstrated by SGN-75 in RCC patients and by our preclinical data suggesting synergy between auristatin-containing ADCs and mTOR inhibitors, including everolimus," Drachman added.

The open-label, dose-escalation trial enrolling patients who have previously been treated with one or two tyrosine kinase inhibitors (TKIs), is designed to evaluate the safety and antitumor activity of SGN-75 in combination with everolimus, an mTOR inhibitor, in patients with CD70-positive metastatic RCC.

The primary endpoint of the trial that is expected to enroll up to 40 patients at multiple centers in the US is safety while the key secondary endpoints include best clinical response, progression-free survival and overall survival.

Barbara Ann Karmanos Cancer Institute oncology associate professor and Phase Ib trial investigator Elisabeth Heath said despite the use of immunotherapy, tyrosine kinase inhibitors and mTOR inhibitors, many patients with kidney cancer experience progression of their disease.

"Kidney cancer tends to resist treatments after it stops responding to initial therapy, clearly demonstrating a need to identify new treatment approaches, such as targeted therapies directed to novel targets and combination therapy," Heath added.

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