Seagen Highlights First Solid Tumor Data for an ADCETRIS (brentuximab vedotin) Immunotherapy Combination and Preclinical Data for Novel CD30-Directed Antibody-Drug Conjugate at Society for Immunotherapy of Cancer (SITC) Annual Meeting - Seite 2

The study is currently enrolling patients in previously untreated NSCLC and head and neck cancer.

SGN-35T, a Novel ADC

SGN-35T is a next generation CD30-directed ADC that uses a novel tripeptide linker designed to preferentially release its cytotoxic payload in tumor cells to limit off-target toxicity. Preclinical data suggest that SGN-35T may be highly effective, like ADCETRIS, with the potential for improved tolerability. SGN-35T is an investigational agent, and its safety and efficacy have not been established.

In this in vitro study, SGN-35T was cytotoxic to CD30-expressing tumor cells and CD30-expressing regulatory T cells, whereas CD8-expressing T cells were unaffected by SGN-35T. The observations support future clinical investigation of SGN-35T in solid tumors.

Key Seagen Data to be Presented

Abstract Title	Abstract #	Presentation	Lead Author
Phase 2 trial of brentuximab vedotin (BV) with pembrolizumab (pembro) in patients with metastatic non-small cell lung cancer or metastatic cutaneous melanoma after progression on anti-PD-1 therapy	699	Poster Nov. 3, 9:00 a.m. – 7:00 p.m. PT	Lee
innovaTV 207 Parts E and F: A phase 2 study of tisotumab vedotin in patients with squamous cell carcinoma of the head and neck (trial in progress)	681	Poster Nov. 3, 9:00 a.m. – 7:00 p.m. PT	Seiwert
Activated regulatory T cells in solid tumors express CD30, which are selectively targeted by the novel anti-CD30 antibody-drug conjugate SGN-35T	1155	Poster Nov. 3, 9:00 a.m. – 7:00 p.m. PT	O’Connor

About ADCETRIS

ADCETRIS is an ADC comprised of a CD30-directed monoclonal antibody attached by a protease-cleavable linker to a microtubule disrupting agent, monomethyl auristatin E (MMAE), utilizing Seagen's proprietary technology. The ADC employs a linker system that is designed to be stable in the bloodstream but to release MMAE upon internalization into CD30-positive tumor cells.