Peregrine Pharmaceuticals has presented a range of clinical, translational, and pre-clinical study results of bavituximab, an investigational phosphatidylserine (PS)-signalling pathway inhibitor.

According to the firm, the study results demonstrated that bavituximab has promoted anti-tumour T cell activity in several tumour types.

Preclinical data showed that combining the enhanced T cell anti-tumour activity of bavituximab-like antibodies with checkpoint inhibitors, such as anti-PD-1 antibodies results in better tumour control in multiple models of cancer.

Peregrine Pharmaceuticals preclinical research vice-president Jeff Hutchins said: "We continue to generate a broad collection of pre-clinical, translational and clinical data highlighting bavituximab’s novel mechanism of action and synergistic activity for a range of combination treatments."

"We continue to generate a broad collection of pre-clinical, translational and clinical data highlighting bavituximab’s novel mechanism of action."

The study also showed that bavituximab-like antibodies significantly increase the prevalence of tumour infiltrating CD8+ T-cells and immune-activating cytokines, while decreasing macrophages and myeloid cells that allow the tumour to evade immune detection.

The data of translational study across multiple cancers suggested that tumours with low PD-L1 or PD-1 expression on tumour infiltrating T cells showed promising signs of immune activation after treatment with bavituximab.

The elucidation and confirmation of bavituximab’s mechanism of action represents the potential of bavituximab to enhance the anti-tumour effects of both chemotherapy and immune checkpoint inhibitors.

In addition, the combination of bavituximab-like antibodies and anti-PD-1 antibodies resulted in enhanced and synergistic anti-tumour activity in animal models of multiple tumour types compared to either agent alone.

Results from several clinical and preclinical studies in a range of tumour types demonstrated that bavituximab and bavituximab-like antibodies, in combination with conventional therapy, have consistently showed estimated survival curves that plateau.