SGN-B6A: A New Vedotin Antibody-Drug Conjugate Directed to Integrin Beta-6 for Multiple Carcinoma IndicationsRobert P. Lyon, Mechthild Jonas, Christopher Frantz, Esther S. Trueblood, Roma Yumul, Lori Westendorf, Christopher J. Hale, Jackie L. Stilwell, Narayana Yeddula, Katie M. Snead, Vineet Kumar, Gabriela I. Patilea-Vrana, Kerry Klussman, Maureen C. Ryan
- Cancer Research
Integrin beta-6, a component of the heterodimeric adhesion receptor alpha-v/beta-6, is overexpressed in numerous solid tumors. Its expression has been shown by multiple investigators to be a negative prognostic indicator in diverse cancers including colorectal, non-small cell lung, gastric, and cervical. We developed SGN-B6A as an antibody-drug conjugate (ADC) directed to integrin beta-6 to deliver the clinically validated payload monomethyl auristatin E (MMAE) to cancer cells. The antibody component of SGN-B6A is specific for integrin beta-6 and does not bind other alpha-v family members. In preclinical studies, this ADC has demonstrated activity in vivo in models derived from non-small cell lung, pancreatic, pharyngeal, and bladder carcinomas spanning a range of antigen expression levels. In nonclinical toxicology studies in cynomolgus monkeys, doses of up to 5 mg/kg weekly for four doses or 6 mg/kg every 3 weeks for two doses were tolerated. Hematologic toxicities typical of MMAE ADCs were dose limiting, and no significant target-mediated toxicity was observed. A phase 1 first-in-human study is in progress to evaluate the safety and antitumor activity of SGN-B6A in a variety of solid tumors known to express integrin beta-6 (NCT04389632).