Marie Humbert-Droz, PhDMay 2026

I’m a scientist-turned-engineer
who keeps ending up at the
start of things.

I came to healthcare AI from computational chemistry, and I’ve stayed because the problems are real, the data is harder than people think, and the field is still figuring out what good looks like.

Now
Founding ML EngineerTimeless Biotech · 2025–
Before
Foundig ML ScientistLighten Platforms · 2024–25
Training
PhD, Comp. ChemistryUniversity of Geneva

I build clinical machine learning end to end — the model, the validation that proves it holds up, and the system that turns it into something a clinician actually uses. The model is usually the smallest part. Most of the work is everything between a result that’s true and a result that’s in front of the right person at the right moment.

I’m currently founding ML engineer at Timeless Biotech, where I built MenoTime — an ovarian-age prediction platform — from the survival model through the deployed product. Before Timeless I was founding ML scientist at Lighten Platforms, where I built an LLM system that abstracted clinical concepts across entire patient records, and learned in detail what goes wrong when language models meet messy clinical text.

My background is in computational chemistry — a PhD from Geneva and a decade of working with noisy data and the honest reporting of uncertainty. That training is where I learned to treat validation as a discipline that runs through every layer of a model — cross-validation, calibration, generalization, deployment monitoring — rather than a final box to check before publication. I left the bench for real-world data, and academia to see models actually deployed. That instinct — toward the messy, used, real version of the work — is still most of the job.

I write about healthcare ML, clinical LLMs, and women’s health data.

Three projects, three decisions that mattered more than the model.

01 / MenoTime
2025–2026
Survival analysis,
Clinical ML,
Interpretability

Building the model and the framework to interpret it.

The product needed a survival model that would work across an unusually long horizon — three decades of reproductive aging, where most clinical models give up after five or ten years. I built it from scratch on longitudinal hormone and biomarker data, then spent as much time on what the model was for as on the model itself.

Interpretation is part of the model, not a step that comes after it. Clinicians and patients needed numbers they could act on — which meant translating a survival curve into a small set of metrics that mean something. I developed an ovarian-age framework from scratch: a peer-relative metric for where a patient sits among others her age, a gap metric that lets her track her own progress over time without being confounded by natural aging, and a zone system that translates a continuous prediction into clinically meaningful regions. None of that interpretation language existed in the field before — building it was as much of the work as building the model.

Outcome — A clinical prediction model clinicians can actually use, paired with the language to explain it.
02 / MenoTime
2025–2026
Full-stack,
Deployment,
Product engineering

The report is the product.

A model in a notebook is not a clinical product. The work between those two things is mostly invisible — and it’s most of what decides whether anyone ever uses what you built.

The clinical report is the product. Everything I built around it — patient intake, provider portal, exports, the deployed model behind a versioned API — exists to put the right numbers in the right hands at the right moment in the workflow. The platform flexes across 13 user personas and clinical workflows because the report has to land cleanly regardless of who’s generating it and why.

Most of the past six months has been platform and product engineering — the kind of work that doesn’t show up in ML publications and rarely shows up in case studies, because there’s no clean experimental result to point at. But it’s the part where most clinical AI products actually fail: not because the model was wrong, but because the system around it never reached anyone who could use it.

Outcome — A clinical AI report clinicians can act on, and a system that delivers it across the workflows that matter.
03 / Lighten Platforms
2024–early 2025
LLMs,
Clinical reasoning,
QA pipelines

LLM-powered clinical abstraction across the patient record.

As first technical hire, I designed and shipped a system that used LLMs to abstract complex clinical concepts from de-identified patient records — not just structured fields from a single note, but concepts that required reasoning across an entire patient's longitudinal history, sometimes hundreds of pages of clinical text.

The harder problems were accuracy and trust. I built guardrails to minimize hallucinations in the abstraction step, and a QA pipeline that improved accuracy iteratively rather than relying on the model to be right the first time.

Outcome — An abstraction system that worked across longitudinal records, with the QA scaffolding to keep it honest.

Writing about clinical AI, healthcare ML, and women’s health data.

I like hearing from people building things in healthcare AI.

Questions, collaborations, a model you want a second opinion on, a problem you can’t quite articulate yet — all welcome. The quickest way to reach me is email.