[3] In preclinical studies glembatumumab vedotin was capable of killing GPNMB expressing melanoma and breast cancer cells in vitro[4][5] and inducing partial or complete regression of GPNMB-expressing tumors in mouse models.

In 2015, Celldex announced that it had formed a cooperative research and development agreement with NCI to sponsor two clinical trials for uveal melanoma and pediatric osteosarcoma.

[citation needed] As of June 2011[update], Phase I/II clinical trials of glembatumumab vedotin for the treatment of advanced melanoma[9] and breast cancer[10] have been completed but no official study result was posted.

[13] An accelerated approval Phase II clinical trial (METRIC) investigating glembatumumab vedotin versus capecitabine (2:1 with crossover allowed) has begun in November 2013, expected to enroll 300 patients with GPNMB-expressing metastatic triple negative breast cancer.

[14] Development of the ADC was discontinued in April 2018 after missing the primary endpoint of its study and failed to help women with tough-to-treat metastatic triple-negative breast cancers (TNBC) stay both alive and progression-free for longer than Roche Holding AG's Xeloda (capecitabine).