{
  "api_version": "1",
  "request": {
    "url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Tysabri%C2%AE+%28natalizumab%29",
    "query": {
      "intervention": "Tysabri® (natalizumab)"
    },
    "page_size": 10
  },
  "pagination": {
    "page": 1,
    "page_size": 10,
    "total_count": 16,
    "total_pages": 2,
    "next_page_url": "https://clinicaltrialsfind.com/api/v1/search.json?intervention=Tysabri%C2%AE+%28natalizumab%29&page=2&page_size=10",
    "previous_page_url": null
  },
  "source": "remote",
  "last_synced_at": "2026-10-04T04:50:44.200Z",
  "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": "NCT01070823",
      "title": "JC-Virus (JCV) Antibody Program",
      "overall_status": "COMPLETED",
      "study_type": "OBSERVATIONAL",
      "phases": [],
      "conditions": [
        "Multiple Sclerosis"
      ],
      "interventions": [
        {
          "name": "Tysabri® (natalizumab)",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Biogen",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": null,
        "maximum_age": null,
        "sex": "ALL",
        "summary": "Not listed"
      },
      "enrollment_count": 1096,
      "start_date": "2010-03",
      "completion_date": "2012-06",
      "has_results": false,
      "last_update_posted_date": "2016-10-05",
      "last_synced_at": "2026-10-04T04:50:44.200Z",
      "location_count": 11,
      "location_summary": "Aurora, Colorado • Atlanta, Georgia • Cullman, Georgia + 8 more",
      "locations": [
        {
          "city": "Aurora",
          "state": "Colorado"
        },
        {
          "city": "Atlanta",
          "state": "Georgia"
        },
        {
          "city": "Cullman",
          "state": "Georgia"
        },
        {
          "city": "Barrington",
          "state": "Illinois"
        },
        {
          "city": "Brighton",
          "state": "Massachusetts"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01070823"
    },
    {
      "nct_id": "NCT00477113",
      "title": "TYSABRI Global Observational Program in Safety",
      "overall_status": "COMPLETED",
      "study_type": "OBSERVATIONAL",
      "phases": [],
      "conditions": [
        "Multiple Sclerosis"
      ],
      "interventions": [],
      "intervention_types": [],
      "sponsor": "Biogen",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": null,
        "maximum_age": null,
        "sex": "ALL",
        "summary": "Not listed"
      },
      "enrollment_count": 2207,
      "start_date": "2007-01",
      "completion_date": "2015-05",
      "has_results": false,
      "last_update_posted_date": "2015-06-22",
      "last_synced_at": "2026-10-04T04:50:44.200Z",
      "location_count": 1,
      "location_summary": "Kansas City, Missouri",
      "locations": [
        {
          "city": "Kansas City",
          "state": "Missouri"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00477113"
    },
    {
      "nct_id": "NCT01455220",
      "title": "The Effect of Natalizumab (Tysabri) on Sexual Dysfunction in Multiple Sclerosis",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "NA"
      ],
      "conditions": [
        "Multiple Sclerosis"
      ],
      "interventions": [
        {
          "name": "Tysabri ® (Natalizumab)",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "University of South Florida",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "60 Years",
        "sex": "ALL",
        "summary": "18 Years to 60 Years"
      },
      "enrollment_count": 45,
      "start_date": "2011-01",
      "completion_date": "2014-10",
      "has_results": true,
      "last_update_posted_date": "2017-03-31",
      "last_synced_at": "2026-10-04T04:50:44.200Z",
      "location_count": 1,
      "location_summary": "Tampa, Florida",
      "locations": [
        {
          "city": "Tampa",
          "state": "Florida"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT01455220"
    },
    {
      "nct_id": "NCT00472992",
      "title": "Pregnancy Exposure Registry for Tysabri®",
      "overall_status": "COMPLETED",
      "study_type": "OBSERVATIONAL",
      "phases": [],
      "conditions": [
        "Crohn's Disease",
        "Prenatal Exposure",
        "Multiple Sclerosis",
        "Pregnancy"
      ],
      "interventions": [],
      "intervention_types": [],
      "sponsor": "Biogen",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": null,
        "maximum_age": null,
        "sex": "FEMALE",
        "summary": "Female only"
      },
      "enrollment_count": 376,
      "start_date": "2007-01",
      "completion_date": "2012-07",
      "has_results": false,
      "last_update_posted_date": "2014-08-11",
      "last_synced_at": "2026-10-04T04:50:44.200Z",
      "location_count": 1,
      "location_summary": "Morgantown, West Virginia",
      "locations": [
        {
          "city": "Morgantown",
          "state": "West Virginia"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00472992"
    },
    {
      "nct_id": "NCT02176031",
      "title": "Phase II Trial of Natalizumab + Prednisone for Initial Therapy of Acute GI GVHD",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE2"
      ],
      "conditions": [
        "Graft Versus Host Disease"
      ],
      "interventions": [
        {
          "name": "Natalizumab",
          "type": "DRUG"
        },
        {
          "name": "Methylprednisolone",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Dana-Farber Cancer Institute",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 21,
      "start_date": "2015-01",
      "completion_date": "2019-02",
      "has_results": true,
      "last_update_posted_date": "2020-04-17",
      "last_synced_at": "2026-10-04T04:50:44.200Z",
      "location_count": 2,
      "location_summary": "Boston, Massachusetts",
      "locations": [
        {
          "city": "Boston",
          "state": "Massachusetts"
        },
        {
          "city": "Boston",
          "state": "Massachusetts"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02176031"
    },
    {
      "nct_id": "NCT02159573",
      "title": "Real-world Outcomes on Tecfidera (BG00012, Dimethyl Fumarate) Post-Tysabri (BG00002, Natalizumab)",
      "overall_status": "COMPLETED",
      "study_type": "OBSERVATIONAL",
      "phases": [],
      "conditions": [
        "Relapsing-Remitting Multiple Sclerosis"
      ],
      "interventions": [
        {
          "name": "natalizumab",
          "type": "BIOLOGICAL"
        },
        {
          "name": "dimethyl fumarate",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "BIOLOGICAL",
        "DRUG"
      ],
      "sponsor": "Biogen",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": null,
        "sex": "ALL",
        "summary": "18 Years and older"
      },
      "enrollment_count": 530,
      "start_date": "2014-07",
      "completion_date": "2015-01",
      "has_results": false,
      "last_update_posted_date": "2016-06-07",
      "last_synced_at": "2026-10-04T04:50:44.200Z",
      "location_count": 43,
      "location_summary": "Birmingham, Alabama • Cullman, Alabama • Gilbert, Arizona + 40 more",
      "locations": [
        {
          "city": "Birmingham",
          "state": "Alabama"
        },
        {
          "city": "Cullman",
          "state": "Alabama"
        },
        {
          "city": "Gilbert",
          "state": "Arizona"
        },
        {
          "city": "Phoenix",
          "state": "Arizona"
        },
        {
          "city": "Aurora",
          "state": "Colorado"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02159573"
    },
    {
      "nct_id": "NCT02965170",
      "title": "Validation of a Laboratory Test Measuring Natalizumab (Tysabri®) Serum Levels in MS",
      "overall_status": "COMPLETED",
      "study_type": "OBSERVATIONAL",
      "phases": [],
      "conditions": [
        "Multiple Sclerosis"
      ],
      "interventions": [],
      "intervention_types": [],
      "sponsor": "Rocky Mountain MS Research Group, LLC",
      "sponsor_class": "OTHER",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "80 Years",
        "sex": "ALL",
        "summary": "18 Years to 80 Years"
      },
      "enrollment_count": 109,
      "start_date": "2016-10",
      "completion_date": "2018-05",
      "has_results": false,
      "last_update_posted_date": "2019-04-24",
      "last_synced_at": "2026-10-04T04:50:44.200Z",
      "location_count": 1,
      "location_summary": "Salt Lake City, Utah",
      "locations": [
        {
          "city": "Salt Lake City",
          "state": "Utah"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02965170"
    },
    {
      "nct_id": "NCT00559702",
      "title": "Safety Study of Natalizumab to Treat Multiple Sclerosis (MS)",
      "overall_status": "COMPLETED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE1"
      ],
      "conditions": [
        "Relapsing-Remitting Multiple Sclerosis",
        "Secondary Progressive Multiple Sclerosis"
      ],
      "interventions": [
        {
          "name": "natalizumab",
          "type": "DRUG"
        },
        {
          "name": "standard of care",
          "type": "OTHER"
        }
      ],
      "intervention_types": [
        "DRUG",
        "OTHER"
      ],
      "sponsor": "Biogen",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "65 Years",
        "sex": "ALL",
        "summary": "18 Years to 65 Years"
      },
      "enrollment_count": 76,
      "start_date": "2007-10",
      "completion_date": "2011-11",
      "has_results": false,
      "last_update_posted_date": "2014-09-09",
      "last_synced_at": "2026-10-04T04:50:44.200Z",
      "location_count": 12,
      "location_summary": "Phoenix, Arizona • Scottsdale, Arizona • Berkeley, California + 9 more",
      "locations": [
        {
          "city": "Phoenix",
          "state": "Arizona"
        },
        {
          "city": "Scottsdale",
          "state": "Arizona"
        },
        {
          "city": "Berkeley",
          "state": "California"
        },
        {
          "city": "Centennial",
          "state": "Colorado"
        },
        {
          "city": "Maitland",
          "state": "Florida"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT00559702"
    },
    {
      "nct_id": "NCT04047628",
      "title": "Best Available Therapy Versus Autologous Hematopoietic Stem Cell Transplant for Multiple Sclerosis (BEAT-MS)",
      "overall_status": "RECRUITING",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE3"
      ],
      "conditions": [
        "Relapsing Multiple Sclerosis",
        "Relapsing Remitting Multiple Sclerosis",
        "Secondary Progressive Multiple Sclerosis"
      ],
      "interventions": [
        {
          "name": "Autologous Hematopoietic Stem Cell Transplantation",
          "type": "PROCEDURE"
        },
        {
          "name": "Best Available Therapy (BAT)",
          "type": "BIOLOGICAL"
        }
      ],
      "intervention_types": [
        "PROCEDURE",
        "BIOLOGICAL"
      ],
      "sponsor": "National Institute of Allergy and Infectious Diseases (NIAID)",
      "sponsor_class": "NIH",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "55 Years",
        "sex": "ALL",
        "summary": "18 Years to 55 Years"
      },
      "enrollment_count": 156,
      "start_date": "2020-08-17",
      "completion_date": "2029-10",
      "has_results": false,
      "last_update_posted_date": "2026-09-16",
      "last_synced_at": "2026-10-04T04:50:44.200Z",
      "location_count": 23,
      "location_summary": "Palo Alto, California • Aurora, Colorado • Evanston, Illinois + 18 more",
      "locations": [
        {
          "city": "Palo Alto",
          "state": "California"
        },
        {
          "city": "Aurora",
          "state": "Colorado"
        },
        {
          "city": "Evanston",
          "state": "Illinois"
        },
        {
          "city": "Worcester",
          "state": "Massachusetts"
        },
        {
          "city": "Detroit",
          "state": "Michigan"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT04047628"
    },
    {
      "nct_id": "NCT02241785",
      "title": "Natalizumab as an Efficacy Switch in Participants With Relapsing Multiple Sclerosis After Failure on Other Therapies",
      "overall_status": "TERMINATED",
      "study_type": "INTERVENTIONAL",
      "phases": [
        "PHASE4"
      ],
      "conditions": [
        "Relapsing Multiple Sclerosis"
      ],
      "interventions": [
        {
          "name": "natalizumab",
          "type": "DRUG"
        }
      ],
      "intervention_types": [
        "DRUG"
      ],
      "sponsor": "Biogen",
      "sponsor_class": "INDUSTRY",
      "healthy_volunteers": false,
      "eligibility": {
        "minimum_age": "18 Years",
        "maximum_age": "60 Years",
        "sex": "ALL",
        "summary": "18 Years to 60 Years"
      },
      "enrollment_count": 47,
      "start_date": "2014-09-30",
      "completion_date": "2016-05-02",
      "has_results": true,
      "last_update_posted_date": "2017-06-05",
      "last_synced_at": "2026-10-04T04:50:44.200Z",
      "location_count": 11,
      "location_summary": "Fullerton, California • Aurora, Colorado • Des Moines, Iowa + 8 more",
      "locations": [
        {
          "city": "Fullerton",
          "state": "California"
        },
        {
          "city": "Aurora",
          "state": "Colorado"
        },
        {
          "city": "Des Moines",
          "state": "Iowa"
        },
        {
          "city": "St Louis",
          "state": "Missouri"
        },
        {
          "city": "Plainview",
          "state": "New York"
        }
      ],
      "official_url": "https://clinicaltrials.gov/study/NCT02241785"
    }
  ]
}