Transgene and BioInvent International have enrolled the first patient in a Phase I/IIa clinical trial of the novel dual mechanism-of-action oncolytic Vaccinia virus, BT-001, at Institut Bergonié in France.

Developed with Transgene’s Invir.IO platform, BT-001 is engineered to encode a highly differentiated Treg depleting anti-CTLA4 antibody as well as human GM-CSF cytokine.

The recombinant antibody recognising human CTLA4 was made by n-CoDeR/F.I.R.S.T platforms of BioInvent.

The multi-centre, open-label, dose-escalation trial will analyse BT-001 as a single agent, as well as in combination with anti-PD-1 treatment, pembrolizumab.

It is the first trial to enrol patients in several countries in Europe and an IND submission for the trial in the US is anticipated soon.

The Phase I trial has two parts and Part A will have up to 36 patients with metastatic/advanced solid tumours. They will be given single agent, intra-tumoral administrations of BT-001, in cutaneous or palpable subcutaneous lesions or easily injectable lymph nodes.

Part B will analyse intra-tumoral injections of BT-001 plus pembrolizumab in 12 patients.

The combination treatment in various patient groups with different tumour types will be evaluated in the Phase lla trial.

Transgene noted that the expansion groups will extend the chances of studying the activity of this method for treating other malignancies, which are not traditionally addressed with this type of treatment.

Initially, the trial will be carried out at the UCL Saint Luc in Belgium and at several sites in France, including the Bergonié Institute in Bordeaux, the Gustave Roussy Institute in Paris, Centre Léon Bérard in Lyon, and Hôpital Saint-Louis in Paris.

Transgene chairman and CEO Hedi Ben Brahim said: “We are excited to start this clinical trial with BT-001, which is the result of a very productive collaboration between Transgene and BioInvent.

“This first Invir.IO based oncolytic virus entering the clinic has been shown to induce long-lasting anti-tumour immune responses and abscopal effects in several preclinical tumour models. In these experiments, the activity of BT-001 was further enhanced through combination with an anti-PD-1 antibody treatment.”