Celldex Therapeutics has started patient enrolment in a Phase II clinical trial of CDX-3379 to be evaluated in combination with cetuximab (Erbitux) for the treatment of refractory, advanced head and neck squamous cell carcinoma (HNSCC).
Cetuximab is designed to specifically target EGFR signalling pathway, while CDX-3379 is a human monoclonal antibody being developed to selectively bind and inhibit the activity of ErbB3 (HER3) receptor believed to be associated with cancer cell growth, survival, and resistance.
The multi-centre, open-label, two-stage Phase II trial will assess the combination in around 30 subjects suffering from cetuximab-resistant, advanced HNSCC and have previously undergone treatment with an anti-PD1 checkpoint inhibitor.
Patients will be administered with 12mg/kg CDX-3379 once every three weeks and 400mg/m2 initial dose of cetuximab followed by 250mg/m2 dosage every week until disease progression or intolerance.
Celldex Therapeutics Clinical Science vice-president Christopher Turner said: “Unfortunately, resistance to targeted treatments often develops, and we believe CDX-3379 may play an important role in overcoming it.
“In a Phase Ib study, we saw evidence of antitumor activity among the nine patients with HNSCC who were treated with CDX-3379 in combination with cetuximab, including a durable complete response in a patient who had previously progressed on single-agent cetuximab.”
The primary objective of the Phase II trial is the anti-tumour efficacy of CDX-3379, measured through objective response rate when combined with cetuximab.
Secondary objectives such as safety, pharmacokinetics and immunogenicity will also be measured for the combination, along with further evaluation of anti-tumour activity.