Last reviewed 2026-05-25 · How we verify

Rostil (RIOPROSTIL)

Phase 2 active Small molecule ✓ Verified May 2026

Rostil (generic name: RIOPROSTIL) is a rioprostil drug. It is currently in Phase 2 development.

Rostil works by binding to the prostaglandin E2 receptor EP2 subtype, mimicking the action of prostaglandin E2 in the body.

Rostil is a small molecule with the synonyms BAY 06893, BAY-06893, ORF 15927, ORF-15927, RIOPROSTIL, and RIOPROSTIL.

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	RIOPROSTIL
Drug class	rioprostil
Target	Prostaglandin E2 receptor EP2 subtype
Modality	Small molecule
Therapeutic area	Pain
Phase	Phase 2

Mechanism of action

Think of prostaglandins like messengers that help different parts of the body communicate with each other. Prostaglandin E2 is one of these messengers that helps to reduce inflammation and pain. Rostil is like a key that unlocks the prostaglandin E2 receptor, allowing it to send these messages and help to reduce inflammation and pain.

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:

Rostil CI brief — competitive landscape report
Rostil updates RSS · CI watch RSS

Frequently asked questions about Rostil

What is Rostil?

Rostil (RIOPROSTIL) is a rioprostil drug.

How does Rostil work?

Rostil works by binding to the prostaglandin E2 receptor EP2 subtype, mimicking the action of prostaglandin E2 in the body.

What is the generic name of Rostil?

RIOPROSTIL is the generic (nonproprietary) name of Rostil.

What drug class is Rostil in?

Rostil belongs to the rioprostil class. See all rioprostil drugs at /class/rioprostil.

What development phase is Rostil in?

Rostil is in Phase 2.

What does Rostil target?

Rostil targets Prostaglandin E2 receptor EP2 subtype and is a rioprostil.

Drug class: All rioprostil drugs
Target: All drugs targeting Prostaglandin E2 receptor EP2 subtype
Therapeutic area: All drugs in Pain

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