Scancell Holdings PLC (AIM:SCLP, OTC:SCNLF) has reported what it described as 'strong' phase II results for its experimental immunotherapy, iSCIB1+, showing a marked improvement in outcomes for patients with late-stage melanoma when added to standard treatments.
The UK-based life sciences group announced that its SCOPE trial, which is assessing the Immunobody DNA-based therapy in combination with established checkpoint inhibitors, showed an overall response rate of 69% in patients with a specific genetic marker.
This group makes up about 80% of the total study population and the response rate is well above the 48 to 50% typically seen with standard care alone.
The study also found that patients treated with iSCIB1+ had a 12-month progression-free survival rate 20 percentage points higher than standard care. Progression-free survival measures the proportion of patients whose disease does not worsen over a given period.
Dr Heather Shaw, principal investigator for the trial at University College London Hospital, said the addition of SCIB1 or iSCIB1+ to standard-of-care checkpoint inhibitors has demonstrated "extremely exciting early signals".
"These findings highlight the real potential for a significant clinical benefit for patients with advanced melanoma, where there is an unmet need,” she added.
iSCIB1+ is a next-generation version of Scancell’s original Immunobody candidate, developed to target a broader group of patients by including additional tumour markers.
It is designed to be combined with immune checkpoint therapies, which help the immune system recognise and attack cancer cells.
According to the results, 68.6% of patients in the main trial groups responded to the therapy, with a disease control rate of 88% and a complete response, meaning no detectable cancer, of 17.9%.
The company said these results compare favourably to both clinical trial and real-world data for currently approved combinations.
The safety profile of iSCIB1+ was similar to that seen with checkpoint inhibitors alone, indicating the new treatment did not add significant side effects.
Immune system responses were also robust, with the therapy generating specific T cell activity linked to deeper and more durable responses. The company said these immune markers could help identify which patients are most likely to benefit in future trials.
Following these results, Scancell is accelerating plans for a larger, global phase IIb/III registration study, which is needed to support potential approval.
The company said it will engage with the US Food and Drug Administration on the design of this trial, with interim results from the next trial group expected around the end of the year.
Scancell’s SCOPE study is running at multiple UK sites and aims to enrol more than 140 patients with advanced melanoma. The company will present the data and take questions from investors and analysts in a webcast at 13:00 BST on Tuesday.