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RP-G28

Ritter Pharmaceuticals, Inc. · Phase 3 active Small molecule Under review

RP-G28 is a Microbiome modulator Small molecule drug developed by Ritter Pharmaceuticals, Inc.. It is currently in Phase 3 development for Hyperammonemia in urea cycle disorder patients. Also known as: galactic-oligosaccharide.

RP-G28 is a non-systemic oral therapeutic that modulates the gut microbiome to improve metabolic and immune function.

RP-G28 is a treatment being studied for lactose intolerance in a Phase 3 clinical trial. The trial, NCT03597516, is evaluating the efficacy, durability, safety, and tolerability of RP-G28 compared to a placebo in patients with lactose intolerance.

Likelihood of approval
58.3% vs 58.3% industry baseline
If approved by FDA: likely 2028–2030
Steps remaining: NDA/BLA submission
Confidence: High
Why this estimate
  • Baseline phase 3 → approval rate +58.3pp
    Industry-wide phase 3 drugs reach approval ~58.3% 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 2028–2030
EMA EU 2029–2031 +0.7 yr
MHRA GB 2029–2031 +0.7 yr
Health Canada CA 2029–2032 +0.9 yr
TGA AU 2029–2032 +1.2 yr
PMDA JP 2029–2032 +1.5 yr
NMPA CN 2030–2033 +2.3 yr
MFDS KR 2029–2032 +1.4 yr
CDSCO IN 2029–2033 +1.8 yr
ANVISA BR 2030–2033 +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 nameRP-G28
Also known asgalactic-oligosaccharide
SponsorRitter Pharmaceuticals, Inc.
Drug classMicrobiome modulator
ModalitySmall molecule
Therapeutic areaGastroenterology / Metabolic Disease
PhasePhase 3

Mechanism of action

RP-G28 works by selectively promoting the growth of beneficial commensal bacteria in the gastrointestinal tract, thereby restoring a healthier microbiome composition. This microbiome modulation is intended to improve intestinal barrier function, reduce systemic inflammation, and enhance metabolic parameters without requiring systemic absorption of the drug itself.

Approved indications

Common side effects

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 RP-G28

What is RP-G28?

RP-G28 is a Microbiome modulator drug developed by Ritter Pharmaceuticals, Inc., indicated for Hyperammonemia in urea cycle disorder patients.

How does RP-G28 work?

RP-G28 is a non-systemic oral therapeutic that modulates the gut microbiome to improve metabolic and immune function.

What is RP-G28 used for?

RP-G28 is indicated for Hyperammonemia in urea cycle disorder patients.

Who makes RP-G28?

RP-G28 is developed by Ritter Pharmaceuticals, Inc. (see full Ritter Pharmaceuticals, Inc. pipeline at /company/ritter-pharmaceuticals-inc).

Is RP-G28 also known as anything else?

RP-G28 is also known as galactic-oligosaccharide.

What drug class is RP-G28 in?

RP-G28 belongs to the Microbiome modulator class. See all Microbiome modulator drugs at /class/microbiome-modulator.

What development phase is RP-G28 in?

RP-G28 is in Phase 3.

What are the side effects of RP-G28?

Common side effects of RP-G28 include Gastrointestinal symptoms (bloating, gas, diarrhea), Abdominal discomfort.

Related

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