Promethera® Biosciences Presents Updated Clinical Results at AASLD 2019 for World’s First Stem Cell Therapy Trial using HepaStem™ in ACLF

Promethera® Biosciences SA, a global innovator in cell-based medicines and liver diseases, published updated clinical data from the ongoing phase 2a study (HEP101) of its lead product candidate HepaStem™ in patients with Acute-on-Chronic Liver Failure (ACLF) or Acute Decompensation (AD) at high risk of developing ACLF. The data were presented in an oral presentation at the Annual Meeting of the American Association for Study of Liver Diseases (AASLD) on November 10, 2019, in Boston, by Promethera®’s principal investigator Prof. F. Nevens, KULeuven, Belgium. The data set confirmed earlier findings presented at The International Liver Congress™ - ILC 2019 in April.

Currently, liver transplant is the only rescue treatment for patients suffering from ACLF and to a lesser degree for patients with Acute Decompensation of the liver (AD). There are no other existing therapies that can rescue the end-stage-liver failure. Promethera® is developing HepaStem™ as an alternative to transplant; it consists of liver derived stem cells that are obtained from ethically donated healthy human organs and expanded in GMP culture conditions. These liver derived signaling stem cells migrate through the blood stream to reach the liver, where they support the tissue regeneration via their potent secretome.

In the trial HEP101, HepaStem™ has been intravenously infused in single or repeated injections in multiple ascending doses in patients to assess the tolerability and the safety profile of the treatment. The trial which recruited a total of 24 patients, including 16 patients with ACLF and 8 patients with AD has met its primary endpoint.

With one or two repeated doses up to 1.2 million cells per kilogram of body weight, no adverse events related to HepaStem™ occurred and no clinically significant changes were shown in platelet count, fibrinogen levels, and coagulation factors following HepaStem™ infusion. The demonstrated safety of two infusions of 1.2 million cells per kilogram of body weight provide solid guidance for conducting the subsequent trials. In addition to the positive safety profile, the study has shown trends in efficacy with improvement in three indicators of liver disease severity; Model for End Stage Liver Disease score (MELD), Child-Pugh score and bilirubin levels, 28 days and three months after treatment initiation. Promethera® plans to demonstrate the efficacy of HepaStem™ at 1.0 million cells per kilogram of body weight in ACLF with a large multicentric double blind placebo-controlled trial (HEP102). The study HEP102 is expected to start end 2019.


“We continue to pioneer the use of liver stem cells for the treatment of severe liver diseases and the updated status from the world’s first clinical trial evaluating a cell-based therapy in ACLF gives us confidence about the safety aspects and the broad therapeutic potential of our therapy,” said Etienne Sokal, M.D., Ph.D., Promethera®’s Group Chief Medical Officer. “As a potential first tangible alternative to organ transplantation for an ever-growing patient population, HepaStem™ will advance into a larger efficacy trial in ACLF focusing on a reduced need for transplantation and a decreased mortality.”


Prof. Nevens added, “With the data set having evolved since we last presented results at this years’ ILC Congress, the Phase 2a trial provides a strong rationale for further clinical evaluation of the therapeutic concept and has provided a safe dosing regimen which will guide future studies.”




Promethera® Biosciences is a global innovator in liver therapeutics whose mission is to bring life-saving treatments to reduce the need for liver transplantation. Our lead clinical program, derived from our patented cell technology platform HepaStem™, is designed to benefit from its immune-modulatory and anti-fibrotic properties. In addition to our cell-based pipeline we develop antibody technologies, such as the antiTNF-R1 antibody Atrosimab, to complement and diversify our therapeutic options. We are a team of international experts operating out of facilities in Mont-Saint-Guibert, Belgium, Durham, NC, USA, Tokyo, Japan and Basel, Switzerland.

Promethera®, HepaStem™ and H2stem®, are all registered trademarks of the Promethera® Biosciences group.


Contact Information:
Promethera® Biosciences SA
Alexandra Schiettekatte
Global Associate Director Communications & Spokesperson


For Media:
MacDougall Communications
M. Brkulj or Shai Biran, PhD
+ 49 89 2420 9345 or +1 781-235-3060



Interested in a regular update of the Life Sciences and biotech sector in Flanders?