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Taking peoplePhase 2

Vortosiran for people at risk of venous blood clots, including those with cancer

Tests vortosiran in adults with past blood clots or cancer at high clot risk.

Key facts

Who runs it
Ribocure Pharmaceuticals AB
Where
Bulgaria, France, Poland, and Romania30 sites in 4 countriesChoose a country to see its sites
Trial code
Registry title
Study to assess the safety, tolerability, and effects of vortosiran in two groups: participants who previously had a blood clot and completed initial blood-thinner treatment, and participants with cancer who are at high risk of blood clots
Status
Recruiting
Phase
Phase 2
People taking part
150 people, planned
Started
4 Nov 2026
Expected to end
29 May 2028
Type of study
Interventional
Record updated
27 October 2026

Who can take part

AI summary

From the trial's eligibility criteria. Machine-read from the registry text on this page, so it can be wrong. The registry text below and the trial team decide who can take part.

The trial is looking for adults in two groups. Group A had a blood clot and finished first blood-thinner treatment. Group B has cancer, is starting chemotherapy and has a high risk of blood clots.

Age
18 years and older
Sex
Men and women
Disease stage
Group A: a confirmed blood clot with symptoms in a deep leg vein (at the popliteal vein or higher) and/or in the lung. Must be stable at screening and able to be followed as an outpatient. Group B: newly diagnosed cancer or cancer that has grown, ECOG performance status 0-2, and a Khorana score ≥2.
Earlier treatment
Group A: completed 3 to 12 months of standard blood-thinner treatment at least 2 weeks before joining, with no new clot during that time. Stopping blood thinners must fit local standard care. Group B: starting a new course of chemotherapy meant to last ≥3 months.
Biomarker or test result
Group B: Khorana score ≥2 (a score for blood clot risk).

Main reasons for not taking part

  • Pregnancy or breastfeeding
  • Active hepatitis B, hepatitis C or HIV infection
  • eGFR <30 mL/min (poor kidney function)
  • High bleeding risk, or planned surgery during the trial
  • Group A: a clear need for long-term blood thinners; Group B: planned stem cell transplant or only skin basal/squamous cell cancer, acute leukemia or myeloproliferative neoplasm

The registry criteria, word for word

Show all 24 criteriaShow less

Who can take part

  • Cohort A and B: Adult male and female participants (≥18 years)
  • Cohort B: Initiation of a new course of systemic chemotherapy with a minimum intended duration of ≥3 months
  • Cohort B: Intermediate–high risk of VTE, defined as a Khorana score ≥2 at screening; 2.Cohort A and B: Women of childbearing potential must agree to use highly effective contraception; 3.Cohort A: Objectively confirmed symptomatic index DVT of the lower limbs at the popliteal vein or more proximal, and/or symptomatic PE, documented by objective imaging modalities
  • Cohort A: Completed 3 to 12 months of standard therapeutic anticoagulant therapy for the index VTE episode at least 2 weeks before randomization
  • Cohort A: No recurrent VTE during the initial 3 to 12 months anticoagulant therapy treatment period
  • Cohort A: Clinical equipoise for extended anticoagulation, and discontinuation of anticoagulation is consistent with local standard of care for this patient profile. Specifically, clinical equipoise for extended anticoagulation
  • Cohort A: Hemodynamically stable at screening and, in the investigator’s judgment, suitable for outpatient follow-up
  • Cohort B: Eastern Cooperative Oncology Group performance status 0-2 during screening
  • Cohort B: Newly diagnosed cancer site or progression of malignant disease

Who cannot take part

  • Cohort B: Planned stem cell transplantation
  • Cohort A and B: Planned surgery that may change VTE/bleeding risk during the trial period and no recent surgery (≤2 weeks prior screening)
  • Cohort A: Concomitant antithrombotic therapy that would confound assessment or unacceptably increase bleeding risk
  • Cohort A: Active clinically significant bleeding or conditions associated with unacceptably high bleeding risk
  • Cohort A: Severe uncontrolled hypertension
  • Cohort B: High bleeding risk
  • Cohort B: Hepatic disease with coagulopathy
  • Cohort B: Cancer types not eligible as the sole diagnosis: Basal cell or squamous cell carcinoma of the skin only Acute leukemia Myeloproliferative neoplasm
  • Cohort A and B: Evidence of active hepatitis B virus (HBV), hepatitis C virus (HCV), or human immunodeficiency virus (HIV) infection at screening
  • Cohort A and B: Any serious medical, psychiatric, or social condition that, in the investigator’s opinion, would interfere with trial participation, compliance, or interpretation of trial results
  • Cohort A: Any absolute contraindication to continuation of anticoagulation (eg, recent life-threatening bleeding, intracranial hemorrhage, major spinal/eye surgery with unresolved risk)
  • Cohort A and B: The estimated glomerular filtration rate (eGFR) <30 mL/min
  • Cohort A: Relevant baseline laboratory abnormalities at screening: Hemoglobin <10 g/dL Platelet count <100,000/109 cells/L Alanine Aminotransferase (ALT) or AST (Aspartate Aminotransferase) > 1.5 × Upper Limit of Normal (ULN) Total bilirubin >1.5 × ULN
  • Cohort A and B: Pregnancy or breastfeeding
  • Cohort A: Clear indication for indefinite/extended anticoagulation for any reason

This trial has no sites in United States.

It has sites in 4 countries. Choose a country to see its sites.

About the trial

What the trial wants to find out

To evaluate the pharmacodynamic (PD) effect of vortosiran at two dose levels on Factor XI (FXI) activity at Week 8

Questions to ask the study team

  1. How often do I need to come in, and for how long each time?
  2. Are travel costs paid?
  3. Can I keep my own doctor?
  4. What happens if I want to stop?

Contact the study team: see the registry record

Print a page for my doctor

Data and sources

Registry record
Listed on the EU's official list of trials (CTIS).
Official title
Randomized, Double blind, Phase II Trial of Vortosiran to Evaluate Safety, Tolerability, and Pharmacodynamic Efficacy in Participants with Prior Venous Thromboembolism After Completion of Initial Anticoagulant Therapy (Cohort A) and in Cancer Patients at High Risk of Venous Thromboembolism (Cohort B)
Plain-language title
Vortosiran for people at risk of venous blood clots, including those with cancerGenerated from the registry record. The registry title is the official one.
AI summary
From the trial's eligibility criteria. Read by machine on 15 November 2026.
Record updated
27 October 2026