HipGen: The final meeting in Brussels

Carla Grote
Which city would be a better place to arrange a final Meeting for the European Union-funded project “HipGen” than Brussels?
Since there is none, the final HipGen meeting took place in the artsiest, most impressive, and most elaborate building with a beautiful panorama over Brussels and an ounce of scientific reference and spice: The Atomium.
The building was designed and built in 1958 as a flagship on the occasion of the Brussels World Exhibition. The exhibition was intended to be an expression of the democratic will to maintain peace between all nations, of the belief in both technical and scientific progress, and, finally, of a new, modern, and highly technologized world that would enable people to live a better life.
Scientific progress was also the overall objective pursued by the HipGen study funded by Tobias Winkler under EU Horizon 2020 (Grant 779293): Its aim was to bring the first regenerative therapy for improved recovery after muscle injury to market approval. HipGen is the first phase III study to investigate the effect of allogeneic cell therapy on improved mobilization after hip fracture and represents a new innovative therapy that is at an advanced stage of clinical development: An allogeneic placental cell therapy using PLX-PAD cells to improve mobility after hip fracture arthroplasty.
The final HipGen Meeting started on Monday evening, 12th of September with a dinner in a good atmosphere in the Restaurant Vincent - with some fruitful discussions about goals beyond the end of the funding period of the project.
The Tuesday started early in the Atomium with a warm welcome by Tobias Winkler followed by a short overview of the whole project. He reported about the difficulties in patient recruitment during the pandemic and how the primary endpoint (the Short Physical Performance Battery) was not met. Nevertheless, the HIPGEN study managed to repeat the result of the preclinical work on stromal cell transplantation in muscle injuries as well as the results of phase I/II study, which was done before HIPGEN: the post hoc analysis showed a clinically significant increase of the strength of the abductor muscles of the treated and the untreated legs in PLX patients over one year after injection. However, this increase could not be shown to translate into the chosen main endpoints of the study.
The public session, which had been recorded, was started by Matt Costa, Professor of Orthopaedic trauma surgery at the University of Oxford. He presented the medical need and rationale for regenerative treatment of hip fracture (1,4% total health and social care expenditure in the UK) and gave insights on patient expectations, which can be different from scientific measurements or goals. He called into question if death is the most important parameter out of a patient’s perspective - the question will be, which parameter is important to the patient - and how can we measure it? The patients’ perspective is where the research motivation should come from.
Nitsan Halevy from Pluri Inc. summed up where the process of PLX‐PAD cell characteristics started and showed the huge efforts, which were necessary for logistic tasks, and central and site storage. Vera Degtyareva from ICON presented the status of sites and the actual recruitment timeline, which was affected by COVID-19. 240 patients were recruited in 6 countries, including 59 patients in Germany. She gave an overview of the patient status per country. Guido Moll from Charité gave an overview of why biomarker analysis is important for a clinical trial. The reasons are safety, efficacy pharmacokinetics, pharmacodynamics, and stratification of patients. The major results were described on immune cell composition, immune cell functionality, molecular signature, and alloantigen response.
Ornella Parolini from Fondazione Poliambulanza and Sonia Alves and Melanie Ort from the Charité provided insights into the mechanism of action (MOA). The MOA of placenta-derived cells in muscle trauma was introduced, focusing were the PLX cells´ immunomodulatory effects. The question is: What happens during aging? A number of functions in the immune system changes, aging of skeletal muscle, dysregulation of the immune response to muscle injury, and an increase of muscle damage and fibrosis are leading to continuous de-regeneration. Placental cells are used to modulate the immune capacity, inducing a plethora of therapeutic effects. PLX-PAD cells demonstrate immune modulatory potential (immunological balance and modulate inflammatory degenerative processes).
Sven Geissler presented the hypothesis that PLX-PAD promotes/improves muscle regeneration. Systematic analyses of beneficial effects of PLX-PAD cells on cellular functions of human skeleton muscle myoblast from healthy and elderly (HIPGEN) donors were performed investigating scar tissue formation versus regeneration.
Sebastian Sethe stated prior to the conclusion of the meeting that it was ethical from all points of view to continue the study in order to further support and develop the care for patients with hip fractures. For the future, it is important to address the challenges, consider an international population, and have an open discussion.
Tobias Winkler closed the meeting with the words:” Even though the funding ends now, this is not the end. The consortium will come together and will keep the ongoing projects running. A big thanks again to all the participants!”
Supported by the European Union Horizon 2020 Grant Nr. 779293.