Last reviewed 2026-05-31 · How we verify

ATN-103

Ablynx, a Sanofi company · Phase 2 active Small molecule ✓ Verified May 2026 Quality 0/100

ATN-103 is a Small molecule drug developed by Ablynx, a Sanofi company. It is currently in Phase 2 development.

ATN-103 is a TNF-alpha inhibitor, classified as an antibody inhibitor. It has been studied in clinical trials for conditions including rheumatoid arthritis and has been administered to healthy subjects in a single-dose study.

Likelihood of approval

18.3% vs 15.3% industry baseline

If approved by FDA: likely 2031–2034

Steps remaining: Phase 3 → NDA/BLA submission

Confidence: Medium

Why this estimate

Baseline phase 2 → approval rate +15.3pp
Industry-wide phase 2 drugs reach approval ~15.3% of the time (BIO/Informa 2023 industry benchmark across all therapeutic areas).
Big-pharma sponsor +3.0pp
Ablynx, a Sanofi company is a top-20 pharma sponsor — historical approval rates run ~3pp above average due to scale, regulatory experience, and trial-design quality.

Predicted approval windows by jurisdiction (conditional on FDA approval)

Regulator	Country	Likely year	Lag vs FDA
FDA	US	2031–2034	—
EMA	EU	2032–2035	+0.7 yr
MHRA	GB	2032–2035	+0.7 yr
Health Canada	CA	2032–2036	+0.9 yr
TGA	AU	2032–2036	+1.2 yr
PMDA	JP	2032–2036	+1.5 yr
NMPA	CN	2033–2037	+2.3 yr
MFDS	KR	2032–2036	+1.4 yr
CDSCO	IN	2032–2037	+1.8 yr
ANVISA	BR	2033–2037	+2.3 yr

Hover any row for the lag rationale. Lag estimates are reduced when the drug has FDA Breakthrough or EMA PRIME designation (sponsors file globally in parallel).

Estimate based on the BIO/Informa industry phase transition rates plus per-drug modifiers for therapeutic area, sponsor type, FDA designations, mechanism, and trial design. Per-jurisdiction lags from Tufts CSDD international approval studies. Not investment, clinical or regulatory advice. Methodology: /methodology#likelihood.

At a glance

Generic name	ATN-103
Sponsor	Ablynx, a Sanofi company
Modality	Small molecule
Phase	Phase 2

Approved indications

No approved indications tracked.

Common side effects

No common side effects on file.

Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

ATN-103 CI brief — competitive landscape report
ATN-103 updates RSS · CI watch RSS
Ablynx, a Sanofi company portfolio CI

Frequently asked questions about ATN-103

What is ATN-103?

ATN-103 is a Small molecule drug developed by Ablynx, a Sanofi company.

Who makes ATN-103?

ATN-103 is developed by Ablynx, a Sanofi company (see full Ablynx, a Sanofi company pipeline at /company/ablynx-a-sanofi-company).

What development phase is ATN-103 in?

ATN-103 is in Phase 2.

Manufacturer: Ablynx, a Sanofi company — full pipeline

Primary sources · FDA · ClinicalTrials.gov · EMA · SEC EDGAR · ChEMBL · Wikidata · full sourcing