Despite phase 2 miss, Daiichi Sankyo wants Glycotope lead antibody for cancer ADC

Daiichi Sankyo has teamed up with Glycotope to develop an antibody-drug conjugate with potential in ovarian, lung and breast cancers, using an antibody that didn't hit the mark on its own in a mid-stage trial.

The German biotech is putting its lead PankoMab-GEX candidate gatipotuzumab, which targets the tumor-associated MUC1 antigen and has reached the phase 2b testing stage in ovarian or fallopian tube and peritoneal cancer, into the alliance. Daiichi Sankyo is contributing ADC technology to link the antibody to a cell-killing payload.

In a 60-patient phase 1 dose-escalation trial PankoMab-GEX showed anti-tumor activity, including one complete response, in patients with advanced carcinomas. However, in the phase 2b trial of the drug—reported at the European Society of Medical Oncology (ESMO) meeting in September—the antibody failed to show an improvement in progression-free survival (PFS) compared to placebo when used as a maintenance therapy after chemotherapy in recurrent ovarian cancer.

It's still in development, however, with a spokesperson for Glycotope telling us that while the antibody didn’t show single-agent activity, "we’re currently exploring opportunities for development in combination with chemotherapeutics and/or targeted agents." Daiichi Sankyo's ADC plans add another arm to Glycotope's anti-MUC1 program.

The first stage in the new partnership will be a feasibility study to see how the two technologies can be fitted together, and if that is positive the Japanese company has the right to take a worldwide license to the therapeutic, say the partners. Terms aren’t being disclosed but would include an upfront payment as well as development and sales milestones plus royalties. The spokesperson said the feasibility study should be completed in the middle of 2018.

When cells become cancerous, the sugars on their surface proteins undergo distinct changes that set them apart from healthy cells. Aberrant forms of the cell-surface antigen MUC1 are expressed in many types of cancer, and it is hoped that targeting these will be an effective approach for a number of hard-to-treat tumor types. There have been a number of high-profile failures with MUC1-targeting drugs however, including Merck KGaA's tecemotide which was shelved in 2014.

The new deal comes shortly after the Daiichi Sankyo announced a shake-up in its R&D operations, culling several pipeline candidates in cancer, diabetes and cardiovascular disease, and a string of new licensing agreements in oncology including a link-up with Kite Pharma (now part of Gilead) on CAR-T drug axi-cel in Japan.

“This strategic partnership is part of our overall strategy to maximize the potential of our ADC technology by seeking partnerships where our proprietary linker and payload, as well as our unique protein engineering capabilities, can be applied to new antibodies and targets,” said Tom Held, who heads the ADC task force at Daiichi Sankyo.

Glycotope—which was founded back in 2000 as a spinoff of the Max Delbrück Center for Molecular Medicine in Berlin—focuses on tumor-associated carbohydrate antigens. It has various other PankoMab-GEX drugs in early-stage development including a bispecific version aimed at recruiting T cells to tumor sites and another acting as a checkpoint inhibitor.