BT-001

The identified 4-E03 antibody showed significantly stronger Treg depletion, but equipotent checkpoint blockade, compared with clinically validated αCTLA-4 ipilimumab against CTLA-4-expressing Treg cells in a humanized mouse model in vivo. Our findings demonstrate in vivo proof of concept for spatial restriction of Treg depletion-optimized immune checkpoint blocking, vectorized αCTLA-4 as a highly effective and safe strategy to target CTLA-4. A clinical trial evaluating intratumoral VV-αhCTLA-4 (BT-001) alone and in combination with αPD-1 in metastatic or advanced solid tumors has commenced.

This vector-based delivery is a highly effective and safe strategy to target CTLA-4 which overcomes current limitations of approved αCTLA-4 regimens. A clinical trial evaluating i.t. VVGM-αhCTLA4 (BT-001) alone and in combination with αPD-1 in metastatic or advanced solid tumors has been initiated.

4-E03 shows improved Treg-depleting activity compared with ipilimumab. BT-001 also encodes GM-CSF, the cytokine expressed in clinically advanced products like T-Vec (Imlygic) or Pexa-Vec...A clinical batch of BT-001 has been produced and toxicological evaluation is ongoing. Transgene and BioInvent are preparing CTA and IND filings for a multicentre clinical trial targeting injectable superficial tumors.