A new sub-analysis of the SIRFLOX study of Sirtex Medical's (ASX: SRX) SIR-Spheres Microspheres has boosted the company's share price.
The sub-analysis has been released in abstract form, ahead of a presentation at the 17th European Society for Medical Oncology World Congress on Gastrointestinal Cancer in Spain.
The SIRFLOX study is an international, multi-centre, randomised controlled study that enrolled over 500 patients with metastatic colorectal cancer (mCRC) whose disease was non-resectable and had spread to either the liver alone of the liver plus a limited number of sites outside the liver, including lymph nodes and the lungs.
In March, the company announced that a preliminary analysis of SIRFLOX showed that the primary endpoint had not been achieved.
"The preliminary analysis...shows that adding the company’s SIR-Spheres Y-90 resin microspheres to a current first-line systemic chemotherapy regimen for the treatment of non-resectable metastatic colorectal cancer (mCRC) does not result in a statistically significant improvement in overall Progression-Free Survival (PFS)," the company said in a statement in March.
At the time, the company's share price more then halved. It has regained much of that fall in recent days and weeks.
According to Gilman Wong, CEO of Sirtex Medical, "From a clinical practice perspective, we note both ASCO and WCGIC SIRFLOX data releases have demonstrated the first-line use of SIR-Sheres microspheres delivered a 7.9 month extension of tumour control in the liver, while at the same time having no negative impact on the duration of systemic therapy."
In a statement, the company said, in patients with liver-only metastases, a significant 70.2 per cent improvement in median progression-free survival (PFS) in the liver and 36 per cent reduction in the risk of tumour progression in the liver was reported. For liver-dominant patients, a 32.5 per cent improvement in median PFS in the liver and a 23 per cent reduction in the risk of progression was reported.
"In patients who were stratified according to an intention or no intention to be treated with bevacizumab, the addition of SIR-Spheres microspheres showed a significant improvement in median PFS in the liver of 8.3 months and a 31% lower risk of progression in both groups," it said. "Importantly, the clinical benefit of SIR-Spheres microspheres was not dependent on a patient receiving bevacizumab or not."