{
  "api_version": "1",
  "request": {
    "url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=PA21",
    "query": {
      "intervention": "PA21"
    },
    "page_size": 10
  },
  "pagination": {
    "page": 1,
    "page_size": 10,
    "total_count": 9,
    "total_pages": 1,
    "next_page_url": null,
    "previous_page_url": null
  },
  "source": "remote",
  "last_synced_at": "2026-09-08T02:24:30.329Z",
  "attribution": "Data derived from public ClinicalTrials.gov records. The official record at https://clinicaltrials.gov/ remains the source of truth for current availability, contacts, and full study details.",
  "notes": [
    "This endpoint exposes only public summary fields — no participant contact emails, phone numbers, or scraped investigator contact details.",
    "For contact information and full protocol detail, follow each trial's `official_url` to the ClinicalTrials.gov record.",
    "This API is a navigational aid. It does not provide medical advice, eligibility determinations, or compensation guarantees."
  ],
  "trials": [
    {
      "nct_id": "NCT01452906",
      "title": "A Drug-Drug Interaction Study of Omeprazole and PA21",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1"
      ],
      "conditions": [
        "Healthy"
      ],
      "interventions": [
        {
          "name": "PA21 and Omeprazole with food",
          "type": "DRUG"
        },
        {
          "name": "No PA21; Omeprazole with food",
          "type": "DRUG"
        },
        {
          "name": "PA21 with food, Omeprazole 2hrs later",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Vifor Pharma",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "20 Years",
        "maximum_age": "50 Years",
        "sex": "ALL",
        "summary": "20 Years to 50 Years"
      },
      "enrollment_count": 45,
      "start_date": "2011-09",
      "completion_date": "2011-12",
      "has_results": false,
      "last_update_posted_date": "2011-12-12",
      "last_synced_at": "2026-09-08T02:24:30.329Z",
      "location_count": 1,
      "location_summary": "Anaheim, California",
      "locations": [
        {
          "city": "Anaheim",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01452906"
    },
    {
      "nct_id": "NCT01324128",
      "title": "A Phase 3 Study to Investigate the Safety and Efficacy of PA21, a Phosphate Binder, in Dialysis Patients",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Chronic Kidney Disease Requiring Chronic Dialysis"
      ],
      "interventions": [
        {
          "name": "PA21 (2.5 g tablet containing 500 mg iron)",
          "type": "DRUG"
        },
        {
          "name": "Sevelamer carbonate",
          "type": "DRUG"
        },
        {
          "name": "PA21-1 (1.25 g tablet containing 250 mg iron)",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Vifor Pharma",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 1059,
      "start_date": "2011-03",
      "completion_date": "2012-10",
      "has_results": true,
      "last_update_posted_date": "2014-04-24",
      "last_synced_at": "2026-09-08T02:24:30.329Z",
      "location_count": 1,
      "location_summary": "San Antonio, Texas",
      "locations": [
        {
          "city": "San Antonio",
          "state": "Texas"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01324128"
    },
    {
      "nct_id": "NCT01477424",
      "title": "A Drug-Drug Interaction Study of Warfarin and PA21",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1"
      ],
      "conditions": [
        "Drug Interaction Potentiation"
      ],
      "interventions": [
        {
          "name": "PA21",
          "type": "DRUG"
        },
        {
          "name": "Warfarin",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Vifor Pharma",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "20 Years",
        "maximum_age": "50 Years",
        "sex": "ALL",
        "summary": "20 Years to 50 Years"
      },
      "enrollment_count": 45,
      "start_date": "2011-11",
      "completion_date": "2012-02",
      "has_results": false,
      "last_update_posted_date": "2012-02-16",
      "last_synced_at": "2026-09-08T02:24:30.329Z",
      "location_count": 1,
      "location_summary": "Lenexa, Kansas",
      "locations": [
        {
          "city": "Lenexa",
          "state": "Kansas"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01477424"
    },
    {
      "nct_id": "NCT02688764",
      "title": "A Study to Investigate the Safety and Efficacy of PA21 (Velphoro®) and Calcium Acetate (Phoslyra®) in Paediatric and Adolescent Chronic Kidney Disease (CKD) Patients With Hyperphosphataemia",
      "overall_status": "TERMINATED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Hyperphosphatemia"
      ],
      "interventions": [
        {
          "name": "PA21 (Velphoro®)",
          "type": "DRUG"
        },
        {
          "name": "Calcium Acetate (Phoslyra®)",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Vifor Fresenius Medical Care Renal Pharma",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": null,
        "maximum_age": "18 Years",
        "sex": "ALL",
        "summary": "Up to 18 Years"
      },
      "enrollment_count": 85,
      "start_date": "2016-05-26",
      "completion_date": "2019-02-21",
      "has_results": true,
      "last_update_posted_date": "2019-09-10",
      "last_synced_at": "2026-09-08T02:24:30.329Z",
      "location_count": 22,
      "location_summary": "Birmingham, Alabama • Washington D.C., District of Columbia • Miami, Florida + 17 more",
      "locations": [
        {
          "city": "Birmingham",
          "state": "Alabama"
        },
        {
          "city": "Washington D.C.",
          "state": "District of Columbia"
        },
        {
          "city": "Miami",
          "state": "Florida"
        },
        {
          "city": "Miami",
          "state": "Florida"
        },
        {
          "city": "Orlando",
          "state": "Florida"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02688764"
    },
    {
      "nct_id": "NCT01477411",
      "title": "A Drug-Drug Interaction Study of Digoxin and PA21",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1"
      ],
      "conditions": [
        "Drug Interaction Potentiation"
      ],
      "interventions": [
        {
          "name": "PA21",
          "type": "DRUG"
        },
        {
          "name": "Digoxin",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Vifor Pharma",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "20 Years",
        "maximum_age": "50 Years",
        "sex": "ALL",
        "summary": "20 Years to 50 Years"
      },
      "enrollment_count": 42,
      "start_date": "2011-11",
      "completion_date": "2012-01",
      "has_results": false,
      "last_update_posted_date": "2012-01-18",
      "last_synced_at": "2026-09-08T02:24:30.329Z",
      "location_count": 1,
      "location_summary": "Anaheim, California",
      "locations": [
        {
          "city": "Anaheim",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01477411"
    },
    {
      "nct_id": "NCT01438359",
      "title": "A Drug-Drug Interaction Study of Furosemide and PA21",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1"
      ],
      "conditions": [
        "Healthy"
      ],
      "interventions": [
        {
          "name": "PA21 and Furosemide with food",
          "type": "DRUG"
        },
        {
          "name": "No PA21; Furosemide with food",
          "type": "DRUG"
        },
        {
          "name": "PA21 with food and Furosemide 2hrs later",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Vifor Pharma",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "20 Years",
        "maximum_age": "50 Years",
        "sex": "ALL",
        "summary": "20 Years to 50 Years"
      },
      "enrollment_count": 42,
      "start_date": "2011-07",
      "completion_date": "2011-09",
      "has_results": false,
      "last_update_posted_date": "2011-09-30",
      "last_synced_at": "2026-09-08T02:24:30.329Z",
      "location_count": 1,
      "location_summary": "Anaheim, California",
      "locations": [
        {
          "city": "Anaheim",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01438359"
    },
    {
      "nct_id": "NCT00824460",
      "title": "Study of Phosphate Levels in Patients With Chronic Kidney Disease",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Chronic Kidney Disease"
      ],
      "interventions": [
        {
          "name": "1.25 g PA21 (250 mg iron)",
          "type": "DRUG"
        },
        {
          "name": "5.0 g PA21 (1,000 mg iron)",
          "type": "DRUG"
        },
        {
          "name": "7.5 g PA21 (1,500 mg iron)",
          "type": "DRUG"
        },
        {
          "name": "10.0 g PA21 (2,000 mg iron)",
          "type": "DRUG"
        },
        {
          "name": "12.5 g PA21 (2,500 mg iron)",
          "type": "DRUG"
        },
        {
          "name": "Sevelamer hydrochloride",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Vifor Pharma",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 154,
      "start_date": "2008-12",
      "completion_date": "2010-03",
      "has_results": true,
      "last_update_posted_date": "2014-04-01",
      "last_synced_at": "2026-09-08T02:24:30.329Z",
      "location_count": 9,
      "location_summary": "Arvada, Colorado • Denver, Colorado • Pembroke Pines, Florida + 6 more",
      "locations": [
        {
          "city": "Arvada",
          "state": "Colorado"
        },
        {
          "city": "Denver",
          "state": "Colorado"
        },
        {
          "city": "Pembroke Pines",
          "state": "Florida"
        },
        {
          "city": "Kansas City",
          "state": "Kansas"
        },
        {
          "city": "Fresh Meadows",
          "state": "New York"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00824460"
    },
    {
      "nct_id": "NCT01464190",
      "title": "A Phase 3 Extension Study to Investigate the Long-term Safety, Tolerability and Efficacy of PA21, a Phosphate Binder in Dialysis Patients",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Chronic Kidney Disease Requiring Chronic Dialysis"
      ],
      "interventions": [
        {
          "name": "PA21 (2.5 g tablet containing 500 mg iron)",
          "type": "DRUG"
        },
        {
          "name": "Sevelamer carbonate",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Vifor Pharma",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 659,
      "start_date": "2011-09",
      "completion_date": "2013-04",
      "has_results": true,
      "last_update_posted_date": "2014-04-01",
      "last_synced_at": "2026-09-08T02:24:30.329Z",
      "location_count": 1,
      "location_summary": "San Antonio, Texas",
      "locations": [
        {
          "city": "San Antonio",
          "state": "Texas"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01464190"
    },
    {
      "nct_id": "NCT01324752",
      "title": "A Drug-Drug Interaction Study of Losartan and PA21",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1"
      ],
      "conditions": [
        "Drug Interaction Potentiation"
      ],
      "interventions": [
        {
          "name": "PA21 and Losartan with Food",
          "type": "DRUG"
        },
        {
          "name": "No PA21; Losartan with food",
          "type": "DRUG"
        },
        {
          "name": "PA21 with food and Losartan 2 hours later",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Vifor Pharma",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": true,
      "eligibility": {
        "minimum_age": "20 Years",
        "maximum_age": "50 Years",
        "sex": "ALL",
        "summary": "20 Years to 50 Years"
      },
      "enrollment_count": 36,
      "start_date": "2011-03",
      "completion_date": "2011-06",
      "has_results": false,
      "last_update_posted_date": "2012-12-21",
      "last_synced_at": "2026-09-08T02:24:30.329Z",
      "location_count": 1,
      "location_summary": "Anaheim, California",
      "locations": [
        {
          "city": "Anaheim",
          "state": "California"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01324752"
    }
  ]
}