Paris, France, June 29, 2026 – OTR3, a biotechnology company, announces today that the primary endpoint
was met in its clinical trial MATRISS II.
MATRISS II investigated the efficacy and safety of OTR4132
administered intra-arterially immediately after successful endovascular thrombectomy,
in patients with acute ischemic stroke.
The MATRISS II study was a randomized, double-blinded
and placebo-controlled phase II trial that recruited 60 subjects from 11 major
stroke centres in France. A single dose of OTR4132 selected from pre-clinical
studies and from the prior escalating-dose clinical trial MATRISS was tested versus
placebo. The study protocol was registered on ClinicalTrials.gov - NCT
06700824 and conducted according to ICH good clinical practices.
The primary endpoint for the study was defined as the “Baseline-Adjusted
24-Hour NIHSS score” which is considered a strong predictor of long-term
disability.
Results were statistically significant on
the primary endpoint in the intention to treat analysis (p=0.047).
Even if not powered to demonstrate statistical
significance, all secondary endpoints concurred to support the primary
endpoint particularly on NIHSS score and up to 3 months, 24h-NIHSS
responders' rate, “0 or 1” mRS at 3 months, rate of haemorrhagic
transformations at 24 hours, change in stroke lesion volume, length of hospital
stay. Tolerability and safety were notably better in the treated group.
Detailed results will be published in a scientific
medical journal.
OTR3 is actively preparing the next steps that will require
additional funding.
“Results are very encouraging and consistent with
pre-clinical and first in human studies. They suggest acceleration of recovery
in the few days after stroke. There is a consensus that shorter delay to
clinical improvement after stroke is strongly related to better chances of a
long-term good outcome." said Prof. Olivier
Detante, Principal Investigator of the study, CHU de Grenoble, Neurology, France.
"I am very excited by the MATRISS II results.
I have always been convinced that matrix therapy could represent a new branch
of regenerative medicine, especially for neurological diseases.” said Denis Barritault, co-inventor of the technology, founder
and president of OTR3.
“We are very happy with these results; however, a
larger trial is mandatory to confirm acceleration of recovery and demonstrate a
better long-term outcome.” said Frédéric Sedel,
MD, PhD, Chief Medical Officer and vice president of OTR3.
About Ischemic Stroke Stroke is the third leading cause of death and disability globally.
Ischemic stroke accounts for approximately 85% of all strokes. It is a medical
emergency caused by decreased blood flow to the brain. During the acute phase,
the treatment objective is the restoration of blood flow and the prevention of
subsequent clots. Current therapies remain exclusively limited to intravenous thrombolysis
and endovascular thrombectomy. The rates of functional independence achieved
even after highly effective reperfusion treatments are just below 50%, showing
an unmet clinical need for adjunctive neuroprotective treatments. Significant effort has been made to minimize neuronal damage
following stroke with the use of neuroprotective agents, however, these
treatments have yet to show clinical efficacy and no treatment has been
approved so far in Europe and the USA in this indication.
About OTR3 proprietary RGTA® technology. OTR3 is a privately held French biotechnology company
founded by Denis Barritault and Jean-Pierre Caruelle from University of Paris-Est-Creteil
(https://www.otr3.com). The ReGeneraTing Agents (RGTA®) technology is based on
the central role of the extracellular matrix (ECM) in tissue and organ repair
and regeneration. This regenerative process is regulated by specific signalling
molecules—communication peptides/growth factors—present in the extracellular
space. These molecules are normally stored, protected, and retained by a family
of polysaccharides known as heparan sulfates (HS). Together with matrix
proteins such as collagen, laminin and elastin, they form the structural
scaffold of the ECM. Following tissue injury, enzymes are released that degrade
these ECM components, including HS. As a result, communication peptides and
growth factors are no longer protected and undergo accelerated degradation.
RGTA® are polysaccharides that act as structural and functional biomimetics of
natural HS, while being resistant to enzymatic degradation. The primary
mechanism of action of RGTA® is to replace degraded HS and thereby restore the
ECM scaffold through direct physical interactions with matrix proteins.
Restoration of this scaffold protects communication peptides/growth factors and
is conductive to tissue regeneration.
About OTR4132 OTR4132 is a RGTA® intended to be administered in
situ, just after endovascular thrombectomy to improve functional outcomes in
patients with acute ischemic stroke. The safety of OTR4132 was evaluated in
multiple in vitro and in vivo models from which it could be
concluded that it is likely to have a positive benefit/risk ratio in ischemic
stroke (Khelif et al., 2018, https://pmc.ncbi.nlm.nih.gov/articles/PMC6299437/pdf/thnov08p5814.pdf).
A first-in-human escalating dose trial (“MATRISS”) performed in 19
patients showed no serious adverse event attributable to the device at any of 6
tested doses. The rate of severe intracranial haemorrhages at 24 hours was even
lower in the higher doses groups suggesting a protective effect on the blood
brain barrier. Furthermore, efficacy data (including functional scores and
volumetric measurements) suggested acceleration of recovery at higher doses. Results were published in “clinical drug investigation” by Barreau
et al. (https://pmc.ncbi.nlm.nih.gov/articles/PMC12535512/pdf/40261_2025_Article_1487.pdf ).
For more information, please contact: OTR3 Email: pr@otr3.com
