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ALN-AT3SC

Sanofi · Phase 1 active Small molecule ✓ Verified May 2026 Quality 40/100

ALN-AT3SC is a RNA interference therapeutic Small molecule drug developed by Sanofi. It is currently in Phase 1 development.

ALN-AT3SC uses RNA interference to silence the antithrombin gene, reducing antithrombin levels to promote blood clotting in bleeding disorders.

ALN-AT3SC is an RNAi inhibitor that targets Antithrombin mRNA. It is being studied in clinical trials for the treatment of Hemophilia A and Hemophilia B.

Likelihood of approval
12.6% vs 9.6% industry baseline
If approved by FDA: likely 2033–2036
Steps remaining: Phase 2 → Phase 3 → NDA/BLA submission
Confidence: Medium
Why this estimate
  • Baseline phase 1 → approval rate +9.6pp
    Industry-wide phase 1 drugs reach approval ~9.6% of the time (BIO/Informa 2023 industry benchmark across all therapeutic areas).
  • Big-pharma sponsor +3.0pp
    Sanofi 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 2033–2036
EMA EU 2034–2037 +0.7 yr
MHRA GB 2034–2037 +0.7 yr
Health Canada CA 2034–2038 +0.9 yr
TGA AU 2034–2038 +1.2 yr
PMDA JP 2034–2038 +1.5 yr
NMPA CN 2035–2039 +2.3 yr
MFDS KR 2034–2038 +1.4 yr
CDSCO IN 2034–2039 +1.8 yr
ANVISA BR 2035–2039 +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 nameALN-AT3SC
SponsorSanofi
Drug classRNA interference therapeutic
ModalitySmall molecule
PhasePhase 1

Mechanism of action

ALN-AT3SC is an RNAi therapeutic that targets messenger RNA encoding antithrombin, a natural anticoagulant protein. By reducing antithrombin levels, the drug aims to rebalance the coagulation system in patients with hemophilia and other bleeding disorders, potentially reducing bleeding episodes and the need for factor replacement therapy.

Approved indications

Common side effects

No common side effects on file.

Key clinical trials

Primary sources

Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.

SourceUsed for
ClinicalTrials.govTrial enrolment, design, endpoints, results

Competitive intelligence

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

Frequently asked questions about ALN-AT3SC

What is ALN-AT3SC?

ALN-AT3SC is a RNA interference therapeutic drug developed by Sanofi.

How does ALN-AT3SC work?

ALN-AT3SC uses RNA interference to silence the antithrombin gene, reducing antithrombin levels to promote blood clotting in bleeding disorders.

Who makes ALN-AT3SC?

ALN-AT3SC is developed by Sanofi (see full Sanofi pipeline at /company/sanofi).

What drug class is ALN-AT3SC in?

ALN-AT3SC belongs to the RNA interference therapeutic class. See all RNA interference therapeutic drugs at /class/rna-interference-therapeutic.

What development phase is ALN-AT3SC in?

ALN-AT3SC is in Phase 1.

Related

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