{"registry": "ISRCTN", "registryId": "ISRCTN72251782", "source": "https://www.isrctn.com/ISRCTN72251782", "apiSource": "https://www.isrctn.com/api/trial/ISRCTN72251782/format/default", "fetchedAt": "2026-10-07T17:01:26.909557Z", "license": "CC BY 4.0", "licenseSource": "https://www.isrctn.com/page/faqs#licence-to-post", "study": {"title": "Randomised study to compare aspirin versus hydroxyurea/aspirin in 'intermediate risk' primary thrombocythaemia (PT) and hydroxyurea/aspirin versus anagrelide/aspirin in 'high risk' primary thrombocythaemia", "scientificTitle": "", "acronym": "PT1", "hypothesis": "1. In 'low risk' patients: what is the incidence of vascular occlusion while receiving aspirin alone?  \n2. In 'intermediate risk' patients: does hydroxyurea reduce vascular occlusive events when added to aspirin? \n3. In 'high risk' patients: does anagrelide reduce vascular occlusive events as effectively as hydroxyurea?  \n4. In 'high risk' patients: is anagrelide as effective as hydroxyurea in reducing elevated platelet counts?  \n5. What is the effect of the treatment modalities on quality of life?  \n6. Secondary objective  In 'intermediate' and 'high risk' patients: does treatment modality alter the risk of leukaemic or myelofibrotic transformation?\n\nPlease note as of 08/02/2011 the anticipated end date of this trial has been extended from 31/10/2003 to 31/07/2012 and the participant number has increased from 1200 to 1600.\nAs of 28/08/2012 the anticipated end date of this trial has been extended from 31/07/2012 to 30/04/2014.", "primaryOutcome": "Vascular occlusion, haemorrhagic events, death, drug side-effects, transformation to acute leukaemia or myelofibrosis", "secondaryOutcome": "Not provided at time of registration", "intervention": "\n\t'Low risk': aspirin only \n'Intermediate risk': aspirin/aspirin plus hydroxyurea\n'High risk': aspirin plus hydroxyurea/aspirin plus anagrelide\n\tDrug\n\tPhase III\n\taspirin versus hydroxyurea/aspirin\n      ", "condition": "\n\tLeukaemia\n\tCancer\n\tLeukaemia\n      ", "studyDesign": "Randomised controlled trial", "overallEndDate": "2014-04-30T00:00:00.000Z", "clinicalTrialsGovNumber": "NCT00175838", "lastUpdated": "2012-08-28T00:00:00.000Z", "eligibility": {"inclusion": "All patients over 18 years of age meeting diagnostic criteria of PT", "exclusion": "Severe heart disease excludes patients from the 'high risk' study.", "ageRange": "Adult", "gender": "Not Specified", "participantType": "Patient"}, "recruitment": {"recruitmentStart": "1997-07-01T00:00:00.000Z", "recruitmentEnd": "2014-04-30T00:00:00.000Z", "recruitmentStatusOverride": "", "recruitmentStartStatusOverride": "", "targetEnrolment": "1600", "totalFinalEnrolment": ""}, "countries": ["United Kingdom", "England"], "locations": [{"name": "Department of Haematology", "city": "Cambridge", "state": "", "country": "United Kingdom", "zip": "CB2 2QH"}], "sponsors": [{"organisation": "Medical Research Council (MRC) (UK)", "sponsorType": "Research council"}], "funders": [{"name": "Medical Research Council (MRC) (UK)", "fundRef": "http://dx.doi.org/10.13039/501100000265"}]}, "studySha256": "424bde621d907ebea0c4f26285411304da963b415e0a2c3af4fc24236f7fb755"}