SYNAPTYS and the Missing Middle Between Discovery and Treatment

It can begin with something small enough to dismiss: a familiar route that suddenly feels uncertain, a recent conversation that cannot be recalled, a task done for years that now takes longer than it should. Alzheimer’s disease advances through losses like these, gradually taking hold of memory, judgment and independence. Around 57 million people were living with dementia worldwide in 2021, and Alzheimer’s accounts for roughly 60 to 70 percent of cases. There is still no cure. New treatments have begun to slow decline in some people with early Alzheimer’s, but the disease remains a long way from solved.

In Paris-Saclay, one attempt to widen those treatment possibilities has been unfolding since 2010. SYNAPTYS neuroscience is developing SYS-0108, a patented combination of memantine and vitamin D3. The company is now approaching a decisive transition: from laboratory evidence toward the studies required before a first human trial, planned for 2028. That scientific journey also exposes a wider investment question. France has spent years building policy, institutions and funding around the idea that promising health research should travel further toward patients. SYNAPTYS is now at the point where that public and scientific ecosystem must increasingly meet private capital.

Two Known Molecules, One New Question

Sébastien Lasnier’s starting point was not a new molecule. In 2010, he identified a possible synergy between memantine, an established Alzheimer’s medicine, and vitamin D3. The idea was simple enough to state: if Alzheimer’s is driven by several biological processes, might two known compounds work better together than either does alone?

The simplicity ended there. More than a decade went into exploring, validating and patenting the combination before computer modeling and laboratory studies followed. SYNAPTYS describes SYS-0108 as a fixed combination designed to act on more than one pathway. Because Alzheimer’s is a multifactorial disease, involving several biological processes, there is a clear rationale for combining treatments that may act on different pathways. This approach is already familiar in areas such as oncology, where combinations are often used against complex disease.

The strongest result so far remains preclinical. In laboratory work using injured mouse neurons, SYNAPTYS reported that about 42 percent were preserved under the patented test conditions, compared with 8 percent for memantine and 2 percent for vitamin D3 alone. That is the point at which the story becomes interesting, but not conclusive. A result in cells can justify the next experiment. It cannot tell anyone what will happen in a patient.

The Price of the Next Answer

The next experiment is already more demanding. SYNAPTYS is moving through an in vivo study, testing memory and Alzheimer’s-related biomarkers in mice with research work involving INSERM, France’s national institute for health and medical research. The program is looking at memory performance and areas including tau, amyloid accumulation, neuroinflammation and neurodegeneration.

Around that study sits the less visible work required to move a drug toward the clinic: toxicology, manufacturing preparation, pharmacokinetics, regulatory documentation and other preclinical steps. Taken together, this represents a preclinical program of roughly €4 million. That scale matters because it is attached to a very specific threshold. Before a first person can receive SYS-0108, the company has to produce enough evidence on safety, behavior and manufacture for regulators to allow the next stage.

Biotechnology has an awkward economics here. Each successful stage removes one layer of uncertainty, but the next answer usually costs more to obtain. Sixteen years of work do not make the outcome certain. They make the next question possible.

From Paris-Saclay to Private Capital

SYNAPTYS has developed inside Paris-Saclay, often described as France’s Silicon Valley, an ecosystem built precisely for that progression. Its network includes INSERM and other scientific partners, as well as institutional relationships linked to Paris-Saclay, Bpifrance and France’s wider biotechnology community. The company’s team and committees bring together researchers, clinicians and pharmaceutical experience.

That local picture sits inside a larger French policy ambition. Through France 2030, the government has committed substantial public funding to health innovation, biotherapies, industrialization and the movement of research into clinical and commercial use. Officials have also identified private investment as a necessary part of strengthening the country’s biotechnology sector. In other words, France is trying to solve at national scale the same problem visible inside SYNAPTYS: excellent science is not enough if it cannot cross the expensive middle ground between discovery and use. (presse.economie.gouv.fr)

SYNAPTYS’s own financing plan makes that handover visible. Its materials map roughly €4 million around the preclinical phase, including earlier public or institutional support and the current €2.6 million raise from private sources such as business angels, family offices and funds. If the program advances, the next planned round rises sharply to €35 million for the clinical phase. The science stays in France for the moment, but the search for capital can widen far beyond the laboratory that produced it.

Before the First Patient

That €35 million is where the scale of the wager changes again. SYNAPTYS plans to move into human studies from 2028 and, if development continues successfully, toward Phase 1b/2a before seeking a licensing deal or acquisition. Those later commercial outcomes are ambitions, not guarantees. The most important evidence is still ahead.

This is also where the project becomes easier to understand as an investment story. There is no finished medicine to value, no sales history and no certainty that the asset will survive clinical testing. There is instead a patent position, years of accumulated research, a network of scientific expertise and a sequence of experiments that can either strengthen or weaken the case.

For SYNAPTYS, the distance between a 2010 observation and a possible 2028 human study is measured in far more than time. It is measured in evidence, regulation, institutional support and successive pools of capital. France can build the ecosystem, laboratories can produce the data and investors can finance the next stage, but none of those steps matters in isolation. The journey only becomes real when the science reaches a person. After sixteen years, that first patient is still ahead, which is precisely why the next stage matters.