July 14, 2026: ‘s-Hertogenbosch, the Netherlands – PamDx, an innovative CRO in biomarker research and in-vitro diagnostic services, has announced the publication of results from the prospective, multicenter IOpener® study in the Journal for ImmunoTherapy of Cancer (JITC). The study, conducted in 210 patients with advanced non-small cell lung cancer (NSCLC) across ten hospitals in the Netherlands, shows that the blood-based IOpener® test predicts a patient’s likelihood of benefiting from immune checkpoint inhibitor (ICI) therapy more accurately than the current standard biomarker, the PD-L1 tumor proportion score (TPS).
The prospective IOpener® study was carried out under the supervision of the Erasmus University Medical Center in Rotterdam. It evaluated a novel blood-based kinase activity profiling approach to predict response to immune checkpoint blockade in patients with advanced NSCLC. The multicenter study enrolled 210 patients receiving anti-PD-1 therapy with or without chemotherapy. Researchers analyzed kinase activity in peripheral blood mononuclear cells before treatment and developed a predictive model to identify patients most likely to benefit from immunotherapy. In the validation cohort, a significantly higher progression-free survival (PFS) rate was observed for patients with predicted benefit than for patients without predicted benefit, especially when the kinome-based test was combined with the TPS score (HR=0.38, p<0.001). The test performed particularly well in patients with low or intermediate PD-L1 expression (TPS <50%) – precisely the group in which PD-L1 alone is least informative – identifying a cohort of patients whose 1-year PFS on anti-PD-1 therapy with or without chemotherapy was as low as 16%.
These findings suggest that adding a simple blood draw to the standard pretreatment workup could help physicians identify NSCLC patients unlikely to benefit from anti-PD-1 therapy, so that alternative treatment strategies can be considered. This prospective, blinded validation is an important milestone for the IOpener® test. It shows, in a real-world multicenter setting, that blood-based kinase activity profiling adds meaningful predictive value on top of the PD-L1 test – especially for patients with a low TPS score (between 1% and 49%) and a very low TPS score (<1%).
“A TPS score this low typically indicates that the tumor will likely not respond to single-agent immunotherapy and where current biomarkers often have limited accuracy. That is exactly where clinicians need better tools to guide treatment choices early,” said Professor Ron H.J. Mathijssen, medical oncologist at Erasmus UMC and corresponding author of the study.
“These results are the product of years of close collaboration between PamDx and leading Dutch oncology centers, and they reinforce our confidence in the IOpener platform as a genuinely useful tool for treatment decision-making in those cases where patient and doctor might need more guidance on the best (combined) immunotherapy. We are grateful to everyone who helped bring this study to completion, and we are now working to translate these findings into routine clinical use,” said John Groten, CEO of PamDx.
PamDx thanks the entire IOpener® study team for their dedication to this study: researchers and clinicians at Erasmus UMC (Rotterdam), UMC Groningen, Radboud University Medical Center (Nijmegen), Elisabeth-TweeSteden Ziekenhuis (Tilburg), Diakonessenziekenhuis (Utrecht), Amphia Hospital (Breda), Catharina Hospital (Eindhoven), Amsterdam UMC and Leiden UMC, as well as Sanquin for blood sample processing and Avania B.V. for independent clinical trial oversight.
PamDx also expresses its deep gratitude to the patients who took part in the IOpener® study and their families. It is thanks to their willingness to contribute blood samples and time, often while facing an advanced cancer diagnosis, that this blood-based test could be developed and validated. Their generosity continues to shape a tool that we hope will help future patients receive the right treatment, and sooner.
About IOpener® – A liquid biopsy immunotherapy guidance test
The IOpener® is a blood-based diagnostic test that supports immunotherapy guidance for melanoma and non-small cell lung cancer (NSCLC) patients. The test measures the kinase activity in peripheral blood mononuclear cells isolated from a single tube of the patient’s blood to determine the likelihood of responding to immunotherapy. The test is based on extensive experience with the technology for measuring and interpreting kinase activity to support academic and clinical research. The IOpener®-NSCLC and the IOpener®-melanoma are CE-IVD registered devices that are developed and manufactured in PamDx’s ISO 13485:2016 certified facility.
About PamDx
PamDx, a tradename of PamGene International B.V., has intensified its efforts to develop and commercialize a blood-based immunotherapy guidance test, the IOpener®, to improve patient outcomes. The company’s kinase-activity profiling technology and proprietary software algorithms support clinicians in their treatment decisions using the IOpener® assay. PamDx’s robust and unique peptide microarray technology for multiplex kinase-activity profiling is also used to provide dedicated assay services for patient stratification for clinical trials, biomarker discovery, and gaining mechanistic insights needed to understand human diseases. PamDx is headquartered in ‘s-Hertogenbosch, The Netherlands.
For more information:
Rinie van Beuningen, Vice President Business Development
e-mail: iopener@pamdx.com
phone: +31 (0) 73 615 80 80
PamDx
Wolvenhoek 10
5211 HH ’s-Hertogenbosch
www.pamdx.com
IOpener® is a registered trademark of PamDx.
