Observational Studies in Cancer Associated Thrombosis for Rivaroxaban – United Kingdom Cohort (OSCAR—UK)

Study type

• Study topic:
  Disease /health condition

  Human medicinal product
• Study type:
  Non-interventional study
• Scope of the study:
  Disease epidemiology

  Effectiveness study (incl. comparative)
• Data collection methods:
  Secondary use of data

Non-interventional study

• Non-interventional study design:
  Cohort

  Other
• Non-interventional study design, other:
  Retrospective study

Study drug and medical condition

• Anatomical Therapeutic Chemical (ATC) code:
  (B01AB04) dalteparin

  dalteparin

  (B01AB05) enoxaparin

  enoxaparin

  (B01AB10) tinzaparin

  tinzaparin
• Medical condition to be studied:
  Embolism venous

Population studied

• Short description of the study population:
  The study focused on adults diagnosed with active cancer who experienced hospitalization, emergency department admission, or primary care visit with an incident venous thromboembolism (VTE), being administered rivaroxaban or other direct acting oral anticoagulants (DOACs) or a low molecular weight heparin (LMWH) on or after January 1, 2013 identified from the CPRD GOLD and Aurum HES-linked dataset.; Inclusion criteria: ; • Be ≥18 years of age at the time of anticoagulation initiation ; • Have active cancer and acute DVT and/or PE ; • Treated with rivaroxaban (or any DOAC) or LMWH as their first recorded anticoagulant prescription 7 to 30 days post-acute CAT event diagnosis ; • Have been active in the data set for at least 12-months prior to the index event and had at least one provider visit in the 12-months prior to the acute VTE event; ; Exclusion criteria:; • Evidence of atrial fibrillation, recent hip/knee replacement (with 90 days of CAT), ongoing VTE ; treatment, valvular heart disease defined as any rheumatic heart disease, mitral stenosis or mitral valve repair/replacement ; • History of inferior vena cava filter before cohort entry ; • VKA use between cohort entry and index day (initiation of DOAC or LMWH) ; • Evidence of any type of therapeutic anticoagulation use during all available look-back period per written prescription or patient self-report ; • Initiation of rivaroxaban or other DOACs or LMWH during the study period at non-therapeutic doses (e.g., enoxaparin at a dose other than 1 mg/kg twice daily or 1.5 mg/kg once daily; dalteparin at a dose other than 200 IU/kg of total body weight) ; • Pregnancy ; • Recording indicative of palliative care before cohort entry ; • Any clinically-relevant bleeding-related d hospitalization or VTE recurrence between the initial CAT and the start of observation
• Age groups:
  • Adults (18 to < 46 years)
  • Adults (46 to < 65 years)
  • Adults (65 to < 75 years)
  • Adults (75 to < 85 years)
  • Adults (85 years and over)
• Special population of interest:
  Other
• Special population of interest, other:
  Venous thromboembolism patients
• Estimated number of subjects:
  5000

Study design details

• Main study objective:
  Evaluate the effectiveness (recurrent venous thromboembolism (VTE)) and safety (major bleeding and bleeding-related hospitalization) of rivaroxaban and other direct-acting oral anticoagulants (DOACs) vs. low molecular weight heparin (LMWH) for treatment of cancer-associated thrombosis (CAT) in the UK Clinical Practice Research Datalink (CPRD) dataset.
• Outcomes:
  - The risk of recurrent VTE at 3-months - Composite of any major bleeding or clinically-relevant non-major bleeding-related hospitalization (per the International Society on Thrombosis and Haemostasis (ISTH) criteria 9, 10 for identification of bleeding-associated hospitalizations) at 3-months - All-cause mortality at 3-months, - Recurrent VTE at 6- and 12-months post-index VTE - Composite of any major or clinically-relevant nonmajor bleeding-related hospitalization at 6- and 12-months post-index VTE, including: -- Intracranial hemorrhage (ICH) To see the full list of secondary outcomes please refer to the protocol.
• Data analysis plan:
  Overlap weighting will be used to adjust for potential confounding between treatment cohorts (exposures of interest). Patients receiving rivaroxaban will also be 1:1 matched to LMWH patients based on propensity scores. Analysis of the primary effectiveness and safety endpoints by key subgroups will be performed as well.