En Carta Diagnostics raises €5M to bring hospital-grade Lyme tests into the home

En Carta Diagnostics, a Paris-based diagnostics startup founded in 2022 by Guillaume Horreard and Margot Karlikow, has closed the first tranche of a €5 million Seed round. The equity portion is led by Blue Forest Ventures with participation from Ring Capital, CentraleSupélec Venture, and 50 Partners Health, alongside business angels; Bpifrance has provided €2 million in non-dilutive co-financing. The company describes this as a first closing, with a second tranche to follow.

The test itself

En Carta's technology is an at-home molecular test — not a lateral-flow antibody strip, but a full molecular amplification assay delivering PCR-level accuracy outside a clinical laboratory. The first target is Lyme disease; the pipeline extends to STIs.

The distinction matters. Standard at-home diagnostics for Lyme disease use antibody detection: they measure the immune response, not the pathogen directly. Antibody tests reliably catch Lyme at later stages but miss a significant proportion of early infections, precisely when antibiotic treatment is most effective. PCR-grade molecular tests detect the pathogen's genetic material, providing both higher sensitivity and a narrower window of false negatives.

The engineering challenge is form factor: PCR has historically required thermocyclers, centrifuges, and controlled laboratory conditions. En Carta's claim is that it has miniaturised the assay to a device patients can operate without specialist training, at home, with results comparable to clinical testing.

Why it has not been done before

At-home molecular diagnostics have been technically feasible since COVID validated rapid molecular testing in non-laboratory settings. The barrier has been regulatory: molecular tests face CE-IVD requirements that are more demanding than those for lateral-flow tests, and the path through clinical validation is longer and more expensive. Covid-era emergency authorisations masked this gap; standard regulatory routes do not.

En Carta is navigating that regulatory process now. The €5 million funds the validation studies required for CE-IVD clearance and the path to the first commercial product launch.

The clinical case

The healthcare-system argument is straightforward: Lyme disease is endemic across Central and Northern Europe, chronically underdiagnosed (the antibody test's early-stage sensitivity is estimated at 30-50% in some studies), and expensive to treat when diagnosed late. An accurate at-home test that catches infection in the first two weeks compresses the diagnostic journey from weeks to days and shifts the treatment window.

Whether patients actually adopt home molecular testing — and whether clinicians trust the results in treatment decisions — is the commercial question the round cannot pre-answer. The technology case is clear; the behaviour-change case takes longer to prove.