Amlitelimab
Sanofi's OX40L antibody, tested in severe alopecia areata as an alternative to blocking JAK.
- Developed by
- Sanofi
- Current phase
- Phase 2
- Indications
- Alopecia areata
- Also known as
- SAR445229, KY1005
- Last public activity
- August 2026
- Record confidence
- High
Tests whether it works, at what dose, in a few hundred people.
How it is meant to work
A fully human, non-depleting monoclonal antibody against OX40L, given by subcutaneous injection. It interrupts the T-cell costimulation that drives the autoimmune attack rather than inhibiting the JAK signalling downstream of it — a different point on the same pathway.
Why it matters
Alopecia areata now has approved JAK inhibitors, so the question has moved on to what you give the people they do not work for, and whether a target further upstream can be safer. Amlitelimab's main development is in atopic dermatitis, which means the safety database will be large before any hair-loss filing. This is a placebo-controlled phase 2 proof-of-concept in severe disease; nothing has read out.
Development history
- Phase 2
First Phase 2 trial on record: NCT06444451 — A Study to Evaluate the Efficacy and Safety of Subcutaneous Amlitelimab Monotherapy Compared With Placebo in Adult Participants With Severe Alopecia Areata
ClinicalTrials.gov ↗
Registered trials
Pulled automatically from ClinicalTrials.gov. Matching is by name and development code, so occasional gaps are possible — tell us if you spot one.
A Study to Evaluate the Efficacy and Safety of Subcutaneous Amlitelimab Monotherapy Compared With Placebo in Adult Participants With Severe Alopecia Areata
Sanofi · n=166 · June 2024
Listing a trial is not a recommendation to join one. Eligibility, risks and costs vary enormously — discuss any trial with your own doctor first.