ReST Therapeutics, founded in Paris in September 2020 by chemist Gilles Rubinstenn, develops a pill for the early treatment of post-traumatic stress disorder (PTSD), to be taken in the weeks and months after a traumatic event to stop the disorder from becoming chronic. Its lead candidate, FENM, is a derivative of the dementia drug memantine that blocks a subtype of NMDA receptor in the brain. It was selected in the EIC Accelerator's June 2023 cut-off with a "grant first" award and received an EU grant of €2.49 million for FENM4PTSD, a €3.56 million project from May 2024 to April 2026, according to CORDIS. Its proposal said "FENM will enter First-in-Human in June 2023" and that with EIC support it would "bring FENM to clinical PoC (PhIIb) by 2027".
The first-in-human study, registered in June 2023 for healthy volunteers in Belgium, was withdrawn on 2 May 2024, the day after the EIC project began, with no one enrolled and the reason given as "a new trial should be designed", according to ClinicalTrials.gov. The first report, to April 2025, says ReST had completed nonclinical testing, shown 24-month stability of its clinical product and "intends on submitting an IND with the FDA in Q4 2025", according to the CORDIS reporting page. On 28 May 2026, a month after the project ended, ReST announced that the US Food and Drug Administration had accepted its application for RST-101, clearing a first-in-human trial in healthy volunteers, according to Business Wire via BioSpace.
Company file
- Legal entity
- ReST Therapeutics SAS, SIREN 889 773 941, Paris
- Founder
- Gilles Rubinstenn, chief innovation officer
- General manager
- Anthony R. Franco, US
- Lead drug
- FENM, now RST-101, NMDA receptor antagonist
- Staff
- 3 to 5 employees
- Funding raised
- $8M, of which $5M non-dilutive, per company
- EIC funding
- Grant first
Where ReST Therapeutics Stands Now
ReST now presents itself as based in Paris and New Haven, Connecticut. Its French investor page says it has raised "8 millions de dollars", of which 5 million non-dilutive, and that a Phase 1 trial was planned "dès le premier trimestre 2026", according to ReST Therapeutics; the trial had not started by then. It reported no revenue and a net loss of €544,360 in 2025, according to the French ratios dataset, and a capital increase was registered in November 2025, according to BODACC. No trial for RST-101 has been registered on ClinicalTrials.gov.
"FENM will enter First-in-Human in June 2023 to initiate the clinical demonstration on PTSD."
ReST Therapeutics, EIC project objective (CORDIS)The Technology: Blocking Trauma From Setting In
PTSD is usually treated with therapy and antidepressants months after it has developed. ReST's idea is to intervene early, while traumatic memories are still being consolidated. Its report says FENM outperformed memantine and ketamine in animal tests, reducing fear, anxiety and depression without the dissociation and drowsiness those drugs cause. None of this has been tested in people.
What the EIC Award Promised, and What the Record Shows
The award was meant to take FENM through human trials to a Phase 2b proof of concept and a pharma partnership by 2027. Over the two-year project ReST did manufacturing, stability and preclinical work, formed a joint lab with the CNRS and prepared a US application, planned for the fourth quarter of 2025 and accepted in May 2026. The first human trial it had promised for June 2023 never took place, and a replacement had not started when the project ended.
- First-in-human trialNot deliveredWithdrawn, 0 enrolled.
- US trial clearanceAfter projectFDA, May 2026.
- Clinical product stabilityDelivered24 months, per report.
- Phase 2b proof of conceptNot deliveredNo Phase 1 start announced.
The Money
The EU covered 70% of the project. ReST's operating loss rose from €233,315 in 2021 to €719,613 in 2025. Its "grant first" award left EIC equity for later; no EIC Fund investment has been announced, and the amount of the November 2025 capital increase is not public. A Phase 1, let alone the Phase 2b promised, needs far more money than the company has disclosed.
What Cannot Be Checked
Questions for the EIC
Why the 2023 trial was withdrawn, why the EIC signed a grant in December 2023 premised on a trial that had not started, whether RST-101 is the same molecule as FENM, and when the new trial will begin are not public.
Why Europe Should Care
PTSD affects around 300 million people worldwide, the company says, and ReST's report says no therapy exists for early intervention. A pill that could be given after trauma would matter. But the EIC's money has so far produced preparation, not a single human dose.
What the award promised
Human trials through to a Phase 2b proof of concept by 2027.
What the record shows
A withdrawn first trial, no patients dosed, and FDA clearance to start again.
The Verdict
Three years behind
ReST's drug was due in humans in June 2023. By the end of the EIC project it still was not, and the company is starting over in the United States.
ReST Therapeutics and the EIC have not been asked for comment for this article. It is based entirely on public records and published statements, linked throughout.
