Celldex Therapeutics has begun an open-label Phase l/ll safety and tolerability study of glembatumumab vedotin in patients with gpNMB-positive stage IIIB or IV non-small cell lung cancer (NSCLC) of squamous histology who have previously been treated with platinum-based chemotherapy.
During the study, gpNMB positivity will be determined by a greater than or equal to 5% gpNMB expression in tumour epithelial cells.
Glembatumumab vedotin will be given once every three weeks until disease progression or intolerance. The study is expected to include ten sites in the US.
Celldex noted that glembatumumab vedotin is a fully human monoclonal antibody-drug conjugate (ADC) that targets gpNMB, which is a protein overexpressed by multiple tumour types, such as SCC of the lung, where around 85% of patients overexpress the marker.
Overexpression of gpNMB has been shown to encourage the invasion and metastasis of cancer, and has been related to poor clinical results.
In order to conduct the study, Celldex has entered into a collaborative relationship with PrECOG, which represents a research network established by the Eastern Cooperative Oncology Group (ECOG), and PrECOG.
Currently, glembatumumab vedotin is being evaluated in patients with metastatic triple negative breast cancers that overexpress gpNMB in the registrational METRIC study, as well as in Phase II to treat advanced melanoma patients, who have progressed after at least one checkpoint inhibitor therapy.
The drug has previously been evaluated in a Phase ll study in advanced breast cancer, known as the EMERGE study, in a Phase l/ll study in advanced breast cancer, and a Phase l/ll study in patients with unresectable stage III or IV melanoma.
Celldex and the National Cancer Institute (NCI) in the US, have entered into a cooperative research and development agreement (CRADA), under which the NCI is sponsoring two studies of glembatumumab vedotin; one in uveal melanoma and one in pediatric osteosarcoma.
The Phase l/ll safety and tolerability study will include a dose-escalation phase followed by a two-stage Phase ll portion.
Phase l, which is the dose-escalation portion of the study, will evaluate the safety and tolerability of glembatumumab vedotin at the current dose of 1.9mg/kg and then 2.2mg/kg in order to determine whether higher dosing is feasible in this population.
The first stage of the Phase ll portion of the study will enrol around 20 patients, and if at least two patients achieve a partial response or complete response, a second stage may enrol another 15 patients.
The primary objective of the Phase ll portion of the study is to evaluate the anti-tumour efficacy of glembatumumab vedotin in squamous cell lung cancer, as measured by objective response rate (ORR).
Secondary objectives of the study cover analyses of safety and tolerability and further assessment of anti-tumour activity across a broad range of endpoints.