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azithromycin (Zithromax)

Pfizer · Phase 3 active Small molecule

azithromycin (Zithromax) is a Macrolide antibiotic Small molecule drug developed by Pfizer. It is currently in Phase 3 development for Community-acquired pneumonia, Acute bacterial sinusitis, Acute otitis media. Also known as: Zithromax.

Azithromycin is a macrolide antibiotic that inhibits bacterial protein synthesis by binding to the 50S ribosomal subunit.

Azithromycin is a macrolide antibiotic that inhibits bacterial protein synthesis by binding to the 50S ribosomal subunit. Used for Community-acquired pneumonia, Acute bacterial sinusitis, Acute otitis media.

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
    Pfizer 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 nameazithromycin (Zithromax)
Also known asZithromax
SponsorPfizer
Drug classMacrolide antibiotic
TargetBacterial 50S ribosomal subunit
ModalitySmall molecule
Therapeutic areaInfectious Disease
PhasePhase 3

Mechanism of action

Azithromycin binds to the bacterial 50S ribosomal subunit and inhibits transpeptidation and translocation, thereby preventing peptide bond formation and halting protein synthesis. This bacteriostatic action is effective against a broad spectrum of gram-positive and gram-negative bacteria, as well as atypical organisms. The drug accumulates in tissues and has a long half-life, allowing for convenient dosing regimens.

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 azithromycin (Zithromax)

What is azithromycin (Zithromax)?

azithromycin (Zithromax) is a Macrolide antibiotic drug developed by Pfizer, indicated for Community-acquired pneumonia, Acute bacterial sinusitis, Acute otitis media.

How does azithromycin (Zithromax) work?

Azithromycin is a macrolide antibiotic that inhibits bacterial protein synthesis by binding to the 50S ribosomal subunit.

What is azithromycin (Zithromax) used for?

azithromycin (Zithromax) is indicated for Community-acquired pneumonia, Acute bacterial sinusitis, Acute otitis media, Pharyngitis/tonsillitis, Uncomplicated skin and soft tissue infections.

Who makes azithromycin (Zithromax)?

azithromycin (Zithromax) is developed by Pfizer (see full Pfizer pipeline at /company/pfizer).

Is azithromycin (Zithromax) also known as anything else?

azithromycin (Zithromax) is also known as Zithromax.

What drug class is azithromycin (Zithromax) in?

azithromycin (Zithromax) belongs to the Macrolide antibiotic class. See all Macrolide antibiotic drugs at /class/macrolide-antibiotic.

What development phase is azithromycin (Zithromax) in?

azithromycin (Zithromax) is in Phase 3.

What are the side effects of azithromycin (Zithromax)?

Common side effects of azithromycin (Zithromax) include Diarrhea, Nausea, Abdominal pain, Vomiting, QT prolongation, Hepatotoxicity.

What does azithromycin (Zithromax) target?

azithromycin (Zithromax) targets Bacterial 50S ribosomal subunit and is a Macrolide antibiotic.

Related

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