QBiotics has announced the final efficacy and safety results from the first stage of its two-part Phase 2A clinical trial in patients with Soft Tissue Sarcoma, coinciding with Rare Cancers Awareness Day.
Soft Tissue Sarcoma (STS) is a rare type of cancer that generally forms as a painless tumour in any one of the soft tissues in the body. There were approximately 128,000 new cases of STS globally in 2023, with an incidence growth rate of 0.54 per cent per year.
In stage one of the trial, 11 patients were administered tigilanol tiglate to one or more of their tumours. Ten patients were included in the response-evaluable population, which was those with a tumour assessment at both baseline and 28 days post-treatment.
The primary efficacy endpoint was the Objective Response Rate (ORR) of injected tumours, compared to baseline.
The ORR was 80 per cent, indicating eight out of 10 evaluable patients achieved either complete or partial ablation of their injected tumours or tumour segments at any time during the study. At the tumour level, 22 of 27 (81 per cent) treated tumours showed either complete or partial responses as the Best Observed Response. 14 out of 27 tumours (52 per cent) demonstrated complete ablation, while 8 out of 27 tumours (30 per cent) demonstrated partial ablation.
QBiotics said the results indicate a high level of efficacy for tigilanol tiglate in achieving complete or partial tumour ablation. Importantly, none of the complete responses recurred by six months, the follow-up period, indicating tigilanol tiglate may provide durable responses.
QBiotics CEO and Managing Director, Stephen Doyle, said, "We are delighted with the outcomes from Stage 1 of our Phase IIa Soft Tissue Sarcoma trial.
“Tigilanol tiglate met both its primary and secondary endpoints, and delivered patients an impressive 80% Objective Response Rate in injected tumours,” said Mr Doyle.
“Importantly, none of the 14 fully ablated (destroyed) tumours had recurred by the 6-month follow-up period, suggesting tigilanol tiglate may provide long-term patient benefits.
“Given soft tissue sarcoma is a challenging cancer to treat, achieving this level of clinical activity is highly encouraging,” said Mr Doyle.
“Our thanks to every trial participant, and also to the trial Investigators, Dr Edmund Bartlett and his team at Memorial Sloan Kettering Cancer Center in New York.
“Given the positive results from Stage 1 of the trial – and compelling investigator reports that tigilanol tiglate may improve responses to systemic therapies in metastatic STS – we have progressed with the expansion arm of the study, announced late last year,” said Mr Doyle.
Principal Trial Investigator, Dr Edmund Bartlett, said, “The clinical activity of tigilanol tiglate, which we observed in multiple types of soft tissue sarcoma, was encouraging. I look forward to expanding our experience with this treatment and determining how to integrate it into the care of patients with soft tissue sarcoma.”
Rare Cancers Australia CEO Christine Cockburn added, “These results offer real hope to people living with soft tissue sarcoma and other rare cancers, who too often face limited treatment options and poor outcomes.
“Innovations like tigilanol tiglate show what’s possible when research targets the unmet needs of rare cancer patients.
“We welcome the continued investment in this promising trial, and look forward to seeing its potential realised in clinical practice,” she said.