Review paper on Proenkephalin as a Novel Biomarker for Kidney Function
HENNIGSDORF, Germany 13. October 2017
— SphingoTec GmbH announces in the early release of September 2017 issue of the Journal of Applied Laboratory Medicine the first review about proenkephalin[1] to aid in the still cumbersome assessment of real kidney function and detection of acute kidney injury.
Acute kidney injury is a common and devastating medical condition. Up to 75 % of all critically ill patients have been found to develop AKI – incidence rising. US hospitals alone see 1.7 million cases of AKI and have limited clinical information for prediction, diagnosis and management of the disease hinting towards the global challenge of undiagnosed AKI.
International leading physicians and researchers in the field of kidney diseases, laboratory medicine, intensive and emergency care report, that the detection of proenkephalin as a stable surrogate marker of enkephalins is possible using the commercially available sphingotest® penKid® assay. The review highlights, that numerous clinical studies demonstrated proenkephalin to be a more accurate and timely biomarker to detect real kidney function compared with serum creatinine. Furthermore, the researchers found an ideal correlation with gold standard techniques such as inulin clearance and related methods, to determine the true GFR. In various patient groups, including patients with heart failure or sepsis proenkephalin concentrations have been shown to predict deterioration of kidney function and subsequent clinical outcomes independently from inflammation or other comorbidities. sphingotec is continuously working with its network of researchers and clinicians to confirm these results in further clinical studies.
About sphingotest® penKid®
The sphingotest® penKid® immunoassay from SphingoTec GmbH measures proenkephalin, a stable surrogate marker for the kidney stimulating hormone enkephalin, indicative for the actual need for kidney stimulation. sphingotest® penKid® predicts the future change in serum creatinine up to two days in advance and is unaffected by inflammation or comorbidities. Today, the sphingotest® penKid® has been evaluated in more than 25,000 patients.
About SphingoTec GmbH
SphingoTec GmbH develops innovative biomarkers for diagnosis, prediction and monitoring of acute medical conditions, such as acute heart failure, acute kidney injury and circulatory shock, in order to support patient management and provide guidance for treatment strategies. Furthermore, sphingotec develops biomarkers for the prediction of health risks, such as obesity, cardiovascular diseases and breast cancer, in order to support prevention strategies.
SphingoTec GmbH was established in 2002 and is located in Hennigsdorf near Berlin, Germany. CEO Dr. Andreas Bergmann was one of the founders of B.R.A.H.M.S. AG. As former Chief Research Officer, he was responsible for the development of the “gold standard” sepsis biomarker Procalcitonin (B.R.A.H.M.S. PCT™). For more information, visit www.sphingotec.com.
[1] Remi Beunders, Joachim Struck, Alan H.B. Wu, Alexander Zarbock, Salvatore Di Somma, Ravindra L. Mehta, Jay L. Koyner, Mitra K. Nadim, Alan S. Maisel, Patrick T. Murray, Sean-Xavier Neath, Allan Jaffe and Peter Pickkers (2017) Proenkephalin (PENK) as a Novel Biomarker for Kidney Function The Journal of Applied Laboratory Medicine: An AACC Publication Sep 2017, jalm.2017.023598; DOI: 10.1373/jalm.2017.023598
sphingotec®, sphingotest® and penKid®, are registered trademarks of SphingoTec GmbH in Europe. For information regarding trademarks and other intellectual property applicable to this product, please see www.sphingotec.com.
• New ELISA sphingotest® penKid® enables widespread measurement of the kidney function biomarker Proenkephalin 119-159 (penKid) using standard laboratory equipment. • Only available test to match SphingoTec’s reference chemiluminescence assay, developed with patented high-sensitivity technology to provide consistent results across platforms. Hennigsdorf/Berlin, Germany, April 28 2026 - SphingoTec GmbH announces the launch of the ELISA sphingotest® penKid®, a new assay designed to make testing of its proprietary biomarker broadly accessible to research laboratories and pharmaceutical partners. Providing ease-of-use and precision, the test facilitates large-scale investigations of human kidney function in both acute and broader clinical research contexts. Responding to growing research interest The launch follows increasing demand from the scientific community to study penKid - a biomarker reflecting the current state of kidney function in critical care environments. While SphingoTec’s high-sensitivity sphingotest® penKid® assay serves as the reference method for clinical research and third-party IVD assays, the assay technology requiring dedicated equipment was not easily adoptable in research laboratories. The new ELISA sphingotest® penKid® now allows researchers worldwide to benefit from SphingoTec’s patented detection technology using standard photometers, extending penKid testing capability to a wider range of laboratories. Proven performance and data continuity The ELISA sphingotest® penKid® has been developed to achieve excellent correlation with SphingoTec’s reference chemiluminescence assay, ensuring consistent, high-quality results across different assay platforms. Both methods share the same underlying technology capable of detecting penKid concentrations in the picomolar range. Thanks to this technology transfer, researchers can rely on the same analytical precision and reliability that supported the clinical studies establishing penKid as a valuable kidney function biomarker. The assay’s robust design and German manufacturing ensure durable consistency and reproducibility. With this research-use ELISA, SphingoTec responds to the increasing availability of non-validated assays and encourages researchers to not compromise assay quality and performance to ensure trustworthy results - since data from non-validated tests may reflect assay limitations rather than the true performance of the penKid biomarker. Complementary approaches for clinical use and scientific exploration SphingoTec pursues its commercial strategy for the biomarker penKid through strategic out-licensing partnerships such as Boditech Med, which has developed an IVDR-certified assay for routine clinical use and rapid diagnostics. The newly launched ELISA sphingotest® penKid® represents a complementary initiative, specifically designed to support high-throughput clinical and translational research. Through this dual approach, SphingoTec reaffirms its commitment to fostering scientific collaboration and promoting the broader exploration of penKid across diverse research settings. “Developing the ELISA sphingotest® penKid® reflects our long-term commitment to improving critical care diagnostics,” said Deborah Bergmann, Managing Director and CEO of SphingoTec GmbH. “Beyond its currently validated clinical applications, we see strong potential for penKid to support research and improve diagnostics in other fields where kidney function is relevant. By encouraging scientists worldwide to incorporate penKid into their studies and clinical programs, we aim to accelerate innovation and advance best-fit diagnostic solutions that ultimately improve patient care.” About SphingoTec SphingoTec GmbH ("SphingoTec"; Hennigsdorf near Berlin, Germany) is a biomarker company focusing on the out-licensing of innovative critical care solutions for diagnosing, predicting, and monitoring acute medical conditions. SphingoTec develops its biomarkers to the commercial stage and partners with IVD companies to make them available on different IVD platforms. SphingoTec's proprietary biomarker portfolio includes Proenkephalin A 119-159 (penKid), a biomarker for the assessment of kidney function in critical diseases, and bioactive Adrenomedullin 1-52 (bio-ADM), a biomarker for the assessment of endothelial function in conditions like sepsis. Discover more on www.sphingotec.com Media Contact: Email: press@sphingotec.com Phone +49-3302-20565-0 SphingoTec GmbH Neuendorfstr. 15A 16761 Hennigsdorf, Germany
• PenKid surpasses serum creatinine on Day 1 post-transplant in detecting delayed graft function (DGF), with an AUROC of 0.87 versus 0.56 for creatinine. • PenKid differentiates slow graft function (SGF) from DGF up to 8 days earlier than current methods, supporting more timely clinical decisions. • PenKid levels remain unaffected by kidney replacement therapy (KRT), allowing for more accurate assessment of kidney function. • Independent validation in transplant cohort from Australia confirms performance and broad applicability. Hennigsdorf/Berlin, Germany, July 1, 2025 - Diagnostic company SphingoTec GmbH (“SphingoTec”) announces a landmark study (1) published in Transplant International, led by Heidelberg University Hospital in Germany in collaboration with researchers from Sydney, Australia, which identifies Proenkephalin A 119-159 (penKid) as a reliable biomarker for early and precise assessment of graft function trajectories following kidney transplantation. The research demonstrates that PenKid not only identifies patients at risk for DGF significantly earlier than traditional markers but also distinguishes between slow and delayed graft function with remarkable accuracy, offering clinicians a valuable new tool for patient management. The study prospectively evaluated 159 consecutive kidney transplant recipients at Heidelberg University Hospital and validated findings in an independent cohort from Sydney. PenKid consistently outperformed serum creatinine (SCr) in predicting graft function trajectories, particularly in the critical early post-transplant period. Notably, PenKid’s ability to remain unaffected by KRT—a treatment for severe kidney dysfunction—further sets it apart from SCr, which can be influenced by non-renal factors and KRT itself, thereby enhancing the reliability of graft function assessment. Multivariate analysis confirmed PenKid as the strongest independent predictor of both short-term graft function and 30-day outcomes, underscoring its clinical utility for early risk stratification. The biomarker’s superior granularity allows for nuanced classification of DGF severity, supporting more informed decisions regarding the initiation of dialysis or biopsy and offering potential for individualized patient care. With these findings, penKid steps forward as a practical addition to the transplant clinician’s toolkit, promising to sharpen decision-making for optimal outcomes. Its adoption could help transplant teams act with greater confidence and precision, ultimately strengthening the standard of care in kidney transplantation. ## References 1. Benning L et al. (2025) Proenkephalin A 119-159 in Kidney Transplantation: A Novel Biomarker for Superior Tracking of Graft Function Trajectories. Transpl. Int. 38:14366. doi: 10.3389/ti.2025.14366 About SphingoTec SphingoTec GmbH ("SphingoTec"; Hennigsdorf near Berlin, Germany) is a biomarker company focusing on the out-licensing of innovative critical care solutions for diagnosing, predicting, and monitoring acute medical conditions. SphingoTec develops its biomarkers to the commercial stage and partners with IVD companies to make them available on different IVD platforms. SphingoTec's proprietary biomarker portfolio includes Proenkephalin A 119-159 (penKid), a biomarker for the assessment of kidney function in critical diseases, commercially available on diagnostic platforms AFIAS and Nexus IB10 and bioactive Adrenomedullin 1-52 (bio-ADM), a biomarker for the assessment of endothelial function in conditions like sepsis. Discover more on www.sphingotec.com Contact : Ruxandra Lenz Marketing and Communication SphingoTec GmbH Phone +49-3302-20565-0 Email: press@sphingotec.com