Last reviewed 2026-06-01 · How we verify

S-555739 Dose 1

Shionogi · Phase 2 active Small molecule ✓ Verified Jun 2026

S-555739 Dose 1 is a Small molecule drug developed by Shionogi. It is currently in Phase 2 development.

S-555739 Dose 1 was studied in a clinical trial for Seasonal Allergic Rhinitis. The trial, NCT01651871, was a Phase 2, multicenter, randomized, double-blind study that compared S-555739 Dose 1 to cetirizine HCl Dose 1.

Likelihood of approval

15.3% 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).

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	S-555739 Dose 1
Sponsor	Shionogi
Modality	Small molecule
Phase	Phase 2

Approved indications

No approved indications tracked.

Common side effects

No common side effects on file.

Key clinical trials

Combination Study Of S-555739/Cetirizine HCl In Adult Patients With Seasonal Allergic Rhinitis (PHASE2)

Primary sources

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

Source	Used for
ClinicalTrials.gov	Trial 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:

S-555739 Dose 1 CI brief — competitive landscape report
S-555739 Dose 1 updates RSS · CI watch RSS
Shionogi portfolio CI

Frequently asked questions about S-555739 Dose 1

What is S-555739 Dose 1?

S-555739 Dose 1 is a Small molecule drug developed by Shionogi.

Who makes S-555739 Dose 1?

S-555739 Dose 1 is developed by Shionogi (see full Shionogi pipeline at /company/shionogi).

What development phase is S-555739 Dose 1 in?

S-555739 Dose 1 is in Phase 2.

Manufacturer: Shionogi — full pipeline

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