Last reviewed 2026-06-02 · How we verify

CB-183,315

Cubist Pharmaceuticals LLC, a subsidiary of Merck & Co., Inc. (Rahway, New Jersey USA) · Phase 3 active Small molecule ✓ Verified Jun 2026

CB-183,315 is a Bacterial protein synthesis inhibitor Small molecule drug developed by Cubist Pharmaceuticals LLC, a subsidiary of Merck & Co., Inc. (Rahway, New Jersey USA). It is currently in Phase 3 development for Gram-positive bacterial infections (phase 3 development). Also known as: Surotomycin.

CB-183,315 is a selective inhibitor of bacterial protein synthesis that targets gram-positive pathogens by binding to the bacterial ribosome.

CB-183,315 is a selective inhibitor of bacterial protein synthesis that targets gram-positive pathogens by binding to the bacterial ribosome. Used for Gram-positive bacterial infections (phase 3 development).

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
Cubist Pharmaceuticals LLC, a subsidiary of Merck & Co., Inc. (Rahway, New Jersey USA) 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 name	CB-183,315
Also known as	Surotomycin
Sponsor	Cubist Pharmaceuticals LLC, a subsidiary of Merck & Co., Inc. (Rahway, New Jersey USA)
Drug class	Bacterial protein synthesis inhibitor
Target	Bacterial ribosome
Modality	Small molecule
Therapeutic area	Infectious Disease
Phase	Phase 3

Mechanism of action

CB-183,315 inhibits bacterial protein synthesis through a novel mechanism of action targeting gram-positive bacteria. The drug is designed to overcome resistance mechanisms seen with existing antibiotics. It represents a new class of antibacterial agents developed to address unmet needs in serious gram-positive infections.

Approved indications

Gram-positive bacterial infections (phase 3 development)

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:

CB-183,315 CI brief — competitive landscape report
CB-183,315 updates RSS · CI watch RSS
Cubist Pharmaceuticals LLC, a subsidiary of Merck & Co., Inc. (Rahway, New Jersey USA) portfolio CI

Frequently asked questions about CB-183,315

What is CB-183,315?

CB-183,315 is a Bacterial protein synthesis inhibitor drug developed by Cubist Pharmaceuticals LLC, a subsidiary of Merck & Co., Inc. (Rahway, New Jersey USA), indicated for Gram-positive bacterial infections (phase 3 development).

How does CB-183,315 work?

CB-183,315 is a selective inhibitor of bacterial protein synthesis that targets gram-positive pathogens by binding to the bacterial ribosome.

What is CB-183,315 used for?

CB-183,315 is indicated for Gram-positive bacterial infections (phase 3 development).

Who makes CB-183,315?

CB-183,315 is developed by Cubist Pharmaceuticals LLC, a subsidiary of Merck & Co., Inc. (Rahway, New Jersey USA) (see full Cubist Pharmaceuticals LLC, a subsidiary of Merck & Co., Inc. (Rahway, New Jersey USA) pipeline at /company/cubist-pharmaceuticals-llc-a-subsidiary-of-merck-co-inc-rahway-new-jersey-usa).

Is CB-183,315 also known as anything else?

CB-183,315 is also known as Surotomycin.

What drug class is CB-183,315 in?

CB-183,315 belongs to the Bacterial protein synthesis inhibitor class. See all Bacterial protein synthesis inhibitor drugs at /class/bacterial-protein-synthesis-inhibitor.

What development phase is CB-183,315 in?

CB-183,315 is in Phase 3.

What does CB-183,315 target?

CB-183,315 targets Bacterial ribosome and is a Bacterial protein synthesis inhibitor.

Drug class: All Bacterial protein synthesis inhibitor drugs
Target: All drugs targeting Bacterial ribosome
Manufacturer: Cubist Pharmaceuticals LLC, a subsidiary of Merck & Co., Inc. (Rahway, New Jersey USA) — full pipeline
Therapeutic area: All drugs in Infectious Disease
Indication: Drugs for Gram-positive bacterial infections (phase 3 development)
Also known as: Surotomycin

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