Bio-Thera Solutions has dosed the first subject in Phase I clinical trial of its BAT6026 along with BAT1308 to treat advanced solid tumour patients in Australia.

A highly differentiated monoclonal antibody, BAT6026 acts on OX40 with improved antibody-dependent cellular cytotoxicity (ADCC) functions. BAT1308 is an anti-programmed death-1 (PD-1) antibody being analysed in early-stage trials.

The open-label, multicentre, dose-escalation Phase I trial will assess the safety and tolerability of the combination treatment in individuals with advanced solid tumours. 

Detecting the maximum tolerated dose and recommended Phase II dose (RP2D), pharmacokinetics and initial anti-tumour activity are key goals of the trial.

Subsequently, disease-specific expansion arms will be enrolled at the RP2D in Australia, China and various other countries to further assess BAT6026’s safety and efficacy for various cancers. 

Currently, BAT6026 is being analysed as a monotherapy in a trial in China.

Bio-Thera Solutions CEO Dr Shengfeng Li said: “BAT6026 has demonstrated highly potent anti-tumour activity as a single agent and in combination with BAT1308 in in vivo pharmacology studies.”

So far, anti-OX40 antibodies have not demonstrated the best clinical responses as agonists while new studies showed that their activities connect directly to antibody isotypes and Fc functions.

This indicates that Treg depletion may be vital for boosting clinical outcomes. 

Furthermore, BAT6026 has shown potent Treg depletion activity while also activating T effector cells in a synergistic manner.

In December last year, Bio-Thera initiated dosing in Phase I trial of its TIGIT-targeting monoclonal antibody, BAT6005, in cancer patients.

The multicentre, open-label, dose-escalation trial is designed to assess the safety and tolerability of BAT6005 as monotherapy in individuals with advanced solid tumours.