Seattle Genetics Moves ADC Candidate For Lymphoma To Phase I

Seattle Genetics announced that it has begun the Phase I clinical trial of its antibody drug conjugate (ADC) SGN-CD70A for CD70-positive relapsed or refractory non-Hodgkin lymphoma (NHL) and metastatic renal cell carcinoma (RCC).

SGN-CD70A is an ADC developed through the company’s proprietary ADC technology to utilize PBD dimmers, a class of DNA-crosslinking agents that has potential to be more powerful that current chemotherapy drugs. ADCs are monoclonal antibodies that target tumor cells and deliver cytotoxic agents into those cells. SGN-CD70A also uses an EC-mAb technology to allow uniform drug-loading of the PBD agent to the anti-CD70 antibody to kill cancer cells. The ADC is designed to be stable in the bloodstream and to only release its cytotoxic agent once inside CD70-expressing cells.

The dose-escalation, open-label, multi center Phase I trial will investigate SGN-CD70A’s safety and antitumor activity in patients diagnosed with CD70-positive metastatic RCC or relapsed or refractory NHL, including mantle cell lymphoma and diffuse large B-cell lymphoma. The trial’s primary endpoint is to measure the maximum tolerated dose of SGN-CD70A as well as assess its safety. Seattle Genetics expects to enroll around 95 patients across multiple trial sites in the U.S.

Jonathan Drachman, CMO and EVP of R&D at Seattle Genetics, said that CD70 remains a good target for ADC antigen since it is highly expressed in both diseases and only minimally in healthy tissues. “We are building on the single-agent activity we observed with our former SGN-75 candidate and have designed SGN-CD70A with a goal to have enhanced activity by utilizing our next-generation ADC technology. Our preclinical data demonstrate that this novel ADC is extremely potent in RCC and NHL models, and we are enthusiastic about commencing a clinical trial of SGN-CD70A in patients with a clear need for new therapeutic options.”

The company presented multiple preclinical data of its ADC technology and SGN-CD70A in the 105th Annual Meeting of the American Association for Cancer Research (AACR) in April this year held in San Diego, California.