Protein / target

DNA topoisomerase 4 subunit A

parCP0AFI2Escherichia coli (strain K12)Swiss-Prot
UniProt: P0AFI2NCBI Gene: 75173148
30
Clinical trials
1
Drugs targeting

Protein at a glance

Biological role

ATP binding

Derived from structured UniProt, Open Targets and literature data on this page.

Protein profile

UniProt 2026_02

Canonical identity and biological annotation from UniProt.

Function

Topoisomerase IV is essential for chromosome segregation; it is the principal protein responsible for decatenating newly replicated chromosomes (PubMed:9334322). It relaxes supercoiled DNA (PubMed:12269820, PubMed:16023670, PubMed:21300644). MukB stimulates the relaxation activity of topoisomerase IV and also has a modest effect on decatenation (PubMed:20921377)

Subcellular location

Cell membrane
Domains and Gene Ontology detail (13)

Domains & features

Topo IIA-type catalytic

Gene Ontology

  • Cchromosome
  • Ccytoplasm
  • Ccytosol
  • CDNA topoisomerase type II (double strand cut, ATP-hydrolyzing) complex
  • Cextrinsic component of plasma membrane
  • FATP binding
  • FDNA binding
  • FDNA topoisomerase type II (double strand cut, ATP-hydrolyzing) activity
  • Pchromosome segregation
  • PDNA topological change
  • Pplasmid partitioning
  • Psister chromatid cohesion

752 aa · 84 kDa

Drugs targeting this protein

1

Whether each drug engages this protein directly or through a complex, and how many other targets are recorded for it. Direct binders with few recorded targets are listed first.

Ciprofloxacin
Inhibitor

Topoisomerase IV inhibitor

Acts on a complex — shared with parE · 1 of 4 recorded protein targets

ChEMBL mechanism, action type and target identity. Open Targets clinical status and indications.

Clinical trials

30

Trials of drugs that target this protein — reached indirectly through those drugs, so a trial listed here studies the drug, not the protein.

Population Pharmacokinetics Of Ceftazidime, Ciprofloxacin And Voriconazole In Paediatric Young Patients (< 12 Years Old)NA

COMPLETED · via Ciprofloxacin · NCT01344512

Experimental Human Infection With Isogenic Mutants of Neisseria GonorrhoeaePHASE1

COMPLETED · via Ciprofloxacin · NCT03840811

Phase III Comparison of Adjuvant Chemotherapy W/High-Dose Cyclophosphamide Plus Doxorubicin (AC) vs Sequential Doxorubicin Fol by Cyclophosphamide (A-C) in High Risk Breast Cancer Patients With 0-3 Positive Nodes (Intergroup, CALGB 9394)PHASE3

COMPLETED · via Ciprofloxacin · NCT00590785

An Open-Label Pilot Study of Fundamental Modification of the Gut Microbiota in the Treatment of Refractory Crohn's DiseasePHASE2

COMPLETED · via Ciprofloxacin · NCT03476317

Oral Empirical Therapy of Fever in Low-Risk Neutropenic Cancer Patients: A Prospective, Double-Blind, Randomized, Multicenter Trial Comparing Monotherapy (Single Daily Dose Moxifloxacin) With Combination Therapy (Ciprofloxacin Plus Amoxicillin/Clavulanic Acid)NA

TERMINATED · via Ciprofloxacin · NCT00062231

Randomized, Multi-Institution Trial of Ciprofloxacin Versus Observation for Men With an Elevated Prostate Specific Antigen (PSA)PHASE3

TERMINATED · via Ciprofloxacin · NCT00840294

Show remaining trials (24)
Antibiotic Prophylaxis for HDR Brachytherapy in the Treatment of Prostate Cancer: a Phase III Randomized TrialPHASE3

TERMINATED · via Ciprofloxacin · NCT03862170

A Two-part, Randomized Partially-blinded, Parallelgroup, Placebo- and Active Comparatorcontrolled Phase 1 Study to Evaluate the Photosafety of Repeated Oral Dose of SAR441566 in Healthy Adult ParticipantsPHASE1

COMPLETED · via Ciprofloxacin · NCT05844735

Active Ulcerative Colitis; Placebo Controlled Treatment Trial With Ciprofloxacin and E. Coli NisslePHASE4

COMPLETED · via Ciprofloxacin · NCT01772615

Randomised Open-label Multicenter Study Evaluating Ciprofloxacin in Severe Alcoholic Hepatitis in Addition to Prednisolon TherapyEARLY_PHASE1

COMPLETED · via Ciprofloxacin · NCT02326103

Adalimumab for the Treatment of Perianal Fistulas in Crohn's Disease More Effective Alone or Combined to CiprofloxacinPHASE3

COMPLETED · via Ciprofloxacin · NCT00736983

Multicentre, Prospective, Comparative, Randomized, Double-blind, Double-dummy Study to Assess the Efficacy and Safety of Cefditoren Pivoxil vs. Ciprofloxacin in Uncomplicated Acute CystitisPHASE3

COMPLETED · via Ciprofloxacin · NCT00598403

A One-Directional, Open-Label Drug Interaction Study to Investigate the Effects of Multiple-Dose Ciprofloxacin HCl on the Single-Dose Pharmacokinetics of Quinine in Healthy VolunteersPHASE1

COMPLETED · via Ciprofloxacin · NCT00785980

A Randomized, Single Oral Dose, Two-way Crossover, Open-label, Laboratory Blind, Bioequivalence Study Comparing Ciprofloxacin From Two Different Drug Products After Oral Administration to Healthy Adult Subjects Under Fasting ConditionsPHASE1

COMPLETED · via Ciprofloxacin · NCT05532267

Antibiotic Comparison Exacerbation COPDPHASE3

COMPLETED · via Ciprofloxacin · NCT00791505

Prospective Randomized Clinical Trial Comparing Efficacy Surgical Versus Medical Treatment of Osteomyelitis in Diabetic Foot UlcersNA

UNKNOWN · via Ciprofloxacin · NCT01137903

Ciprofloxacin, Ampicillin-sulbactam and Placebo Prophylaxis in Laparoscopic Cholecystectomy. A Randomized Controlled StudyPHASE4

TERMINATED · via Ciprofloxacin · NCT01888822

Clinical Validation of a Molecular Test for Ciprofloxacin-Susceptibility in Neisseria GonorrhoeaeNA

COMPLETED · via Ciprofloxacin · NCT02961751

Pharmacokinetics of Ciprofloxacin in Pediatric Patients With Emphasis on Renal ExcretionPHASE4

COMPLETED · via Ciprofloxacin · NCT02598362

The Role of the Microbiota in the Systemic Immune ResponseNA

COMPLETED · via Ciprofloxacin · NCT02340182

A Prospective, Randomized, Double-Blind, Sham-Controlled, Multicenter, Phase 3 Study of OTO-201 Given as a Single Administration for Treatment of Acute Otitis ExternaPHASE3

COMPLETED · via Ciprofloxacin · NCT02801370

Efficacy and Safety of tobRamycin Inhalation Solution for Pseudomonas AeruginoSa Eradication in Bronchiectasis (ERASE): a Multi-center, 2×2 Factorial Randomized, Double-blind, Placebo-controlled TrialPHASE4

COMPLETED · via Ciprofloxacin · NCT06093191

Rifaximin for the Secondary Prevention of Spontaneous Bacterial Peritonitis Recurrence in Cirrhotic Patients: A Prospective, Multicenter, Randomized, Open-label, Controlled Phase III StudyPHASE3

WITHDRAWN · via Ciprofloxacin · NCT02011841

Prospective, Open Label Non-comparative, Multi-center Trial to Evaluate the Efficacy and Safety of Cipro® XR 500 mg Once Daily for 3 Days in Treating Female Patients With Acute, Uncomplicated, Symptomatic Lower Urinary Tract InfectionsPHASE4

COMPLETED · via Ciprofloxacin · NCT00669994

A Randomised, Double-blind, Double-dummy, Multi-centre, Comparative Parallel-group Study to Evaluate the Efficacy and Safety of Oral Daily Rifamycin SV-MMX® 400 mg b.i.d. vs. Ciprofloxacin 500 mg b.i.d. in the Treatment of Acute Infectious Diarrhoea in TravellersPHASE3

COMPLETED · via Ciprofloxacin · NCT01208922

A Pilot, Open-Label, Randomized, Single-Dose, Three-Treatment, Three-Period Crossover Study to Evaluate the Effect of Food on the Bioavailability of PrimeC-ER Tablets and the Comparative Bioavailability of PrimeC-ER and Ciprofloxacin Tablets and Celecoxib Capsules, When Co-Administered, in Healthy Adult SubjectsPHASE1

COMPLETED · via Ciprofloxacin · NCT05232461

Randomized Controlled Trial Comparing Ciprofloxacin With Cefepime in Febrile Neutropenic Patients With Hematologic DiseasesPHASE3

COMPLETED · via Ciprofloxacin · NCT00137787

A Randomized, Prospective, Single-Blinded Control Trial to Assess the Need for Antibiotic Prophylaxis With Routine Ureteral Stent Removal After Kidney Stone ProcedureNA

COMPLETED · via Ciprofloxacin · NCT02944825

Determination of Single-dose Intrapulmonary Pharmacokinetics of Ciprofloxacin and Imipenem in Healthy Subjects and Intubated Patients Suffering From Pneumonia Using Bronchoalveolar LavagePHASE1

COMPLETED · via Ciprofloxacin · NCT03177720

A Prospective Randomised Phase III Trial of Early Hospital Discharge Versus Standard Inpatient Management of Cancer Patients With Low-Risk Febrile Neutropenia Receiving Oral Antibiotics. Oral Antibiotics for Neutropenic Sepsis Giving Early Hospital Discharge [ORANGE]PHASE3

UNKNOWN · via Ciprofloxacin · NCT00445497

ClinicalTrials.gov via the drug-target graph.

What's happening now

59

Recent activity around this target, drawn from one canonical event stream. Every item is reached through a drug that targets this protein, so each event is news about that drug rather than about the protein directly.

  1. Industry development2026-07-27
    Catalytic degradation of ciprofloxacin via peroxymonosulfate activation using a UiO66 and amino functionalized silica coated magnetite composite

    Nature — Environmental Sciences · news · via Ciprofloxacin

  2. Label change2026-07-22

    Label change: CIPROFLOXACIN (ANDA076558)

    fda · regulatory · fda · via Ciprofloxacin

  3. Label change2026-07-22

    Label change: CIPROFLOXACIN (ANDA076794)

    fda · regulatory · fda · via Ciprofloxacin

  4. Industry development2026-07-02
    Adsorption of ciprofloxacin onto engineered biochar derived from floating aquatic weed biomass with isotherm kinetic and interaction mechanism analysis

    Nature — Environmental Sciences · news · via Ciprofloxacin

  5. New publication2024-01-07
    Compatible co-administration of BioThrax® vaccine and ciprofloxacin-Results of a randomized open-label drug-vaccine interaction trial.

    Vaccine: X · 2024 · 1 citation · Europe PMC · via Ciprofloxacin

  6. New publication2023-09-12
    Global diversity and antimicrobial resistance of typhoid fever pathogens: Insights from a meta-analysis of 13,000 &lt;i&gt;Salmonella&lt;/i&gt; Typhi genomes.

    eLife · 2023 · 93 citations · Europe PMC · via Ciprofloxacin

  7. Label change2023-08-31

    Label change: CIPROFLOXACIN (ANDA076558)

    fda · regulatory · fda · via Ciprofloxacin

  8. Label change2023-08-31

    Label change: CIPROFLOXACIN (ANDA076558)

    fda · regulatory · fda · via Ciprofloxacin

  9. Label change2023-08-31

    Label change: CIPROFLOXACIN (ANDA076558)

    fda · regulatory · fda · via Ciprofloxacin

  10. Label change2023-08-31

    Label change: CIPROFLOXACIN (ANDA076558)

    fda · regulatory · fda · via Ciprofloxacin

  11. Label change2023-08-31

    Label change: CIPROFLOXACIN (ANDA076558)

    fda · regulatory · fda · via Ciprofloxacin

  12. Label change2023-08-31

    Label change: CIPROFLOXACIN (ANDA076558)

    fda · regulatory · fda · via Ciprofloxacin

Objective event titles are shown unmodified; the event kind and significance line are derived from structured fields. Forefront AttentionEvent stream aggregating Europe PMC Regulatory filings ClinicalTrials.gov.