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Colistimethate sodium (CMS)

Merck Sharp & Dohme LLC · Phase 3 active Small molecule

Colistimethate sodium (CMS) is a Polymyxin antibiotic Small molecule drug developed by Merck Sharp & Dohme LLC. It is currently in Phase 3 development for Multidrug-resistant gram-negative bacterial infections, Cystic fibrosis-associated Pseudomonas aeruginosa infections.

Colistimethate sodium is a prodrug that is hydrolyzed to colistin, which disrupts bacterial cell membranes by binding to lipopolysaccharides and causing cell lysis.

Colistimethate sodium is a prodrug that is hydrolyzed to colistin, which disrupts bacterial cell membranes by binding to lipopolysaccharides and causing cell lysis. Used for Multidrug-resistant gram-negative bacterial infections, Cystic fibrosis-associated Pseudomonas aeruginosa infections.

Likelihood of approval
63.3% 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).
  • Anti-infectives pathway favourability +2.0pp
    Microbiological endpoints + non-inferiority designs raise approval rates above baseline.
  • Big-pharma sponsor +3.0pp
    Merck Sharp & Dohme LLC 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 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 nameColistimethate sodium (CMS)
SponsorMerck Sharp & Dohme LLC
Drug classPolymyxin antibiotic
TargetBacterial lipopolysaccharide (LPS)
ModalitySmall molecule
Therapeutic areaInfectious Disease
PhasePhase 3

Mechanism of action

Colistimethate sodium (CMS) is the inactive methane sulfonate salt of colistin that is converted to active colistin in vivo. Colistin is a polymyxin antibiotic that acts as a cationic detergent, binding to the lipopolysaccharide layer of gram-negative bacteria and disrupting membrane integrity, leading to bacterial cell death. It is primarily used against multidrug-resistant gram-negative organisms.

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 Colistimethate sodium (CMS)

What is Colistimethate sodium (CMS)?

Colistimethate sodium (CMS) is a Polymyxin antibiotic drug developed by Merck Sharp & Dohme LLC, indicated for Multidrug-resistant gram-negative bacterial infections, Cystic fibrosis-associated Pseudomonas aeruginosa infections.

How does Colistimethate sodium (CMS) work?

Colistimethate sodium is a prodrug that is hydrolyzed to colistin, which disrupts bacterial cell membranes by binding to lipopolysaccharides and causing cell lysis.

What is Colistimethate sodium (CMS) used for?

Colistimethate sodium (CMS) is indicated for Multidrug-resistant gram-negative bacterial infections, Cystic fibrosis-associated Pseudomonas aeruginosa infections.

Who makes Colistimethate sodium (CMS)?

Colistimethate sodium (CMS) is developed by Merck Sharp & Dohme LLC (see full Merck Sharp & Dohme LLC pipeline at /company/merck).

What drug class is Colistimethate sodium (CMS) in?

Colistimethate sodium (CMS) belongs to the Polymyxin antibiotic class. See all Polymyxin antibiotic drugs at /class/polymyxin-antibiotic.

What development phase is Colistimethate sodium (CMS) in?

Colistimethate sodium (CMS) is in Phase 3.

What are the side effects of Colistimethate sodium (CMS)?

Common side effects of Colistimethate sodium (CMS) include Nephrotoxicity, Neurotoxicity, Bronchospasm, Injection site reactions.

What does Colistimethate sodium (CMS) target?

Colistimethate sodium (CMS) targets Bacterial lipopolysaccharide (LPS) and is a Polymyxin antibiotic.

Related

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