ClinicalTrials.gg
CompletedNCT06517563Updated May 11, 2026

Effects of VMX-C001 on the Anticoagulant Effect of Different Forms of Heparin

A Phase 1 interventional study of VMX-C001 and Rivaroxaban in Coagulation Disorder, sponsored by VarmX B.V.. Completed at 1 site in Netherlands. Open to participants aged 18 Years to 49 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-05-11.

Sponsored by VarmX B.V. · Phase 1, Interventional, and Treatment

Phase
Phase 1
Study type
Interventional
Enrollment
16
Allocation
Non-randomized
Ages
18 Years to 49 Years
Sex
All
01

Study summary

A single centre, open-label study to assess the effects of VMX-C001 in combination with an oral FXa DOAC on the efficacy of Unfractionated Heparin (UFH) and of VMX-C001 alone on the efficacy of Low Molecular Weight Heparin (LMWH) in healthy subjects conducted in two parts:

UFH cohort: Subjects will be administered 2 single doses of 5000 IU UFH i.v. on Day 1 and Day 5, oral doses of the DOAC Rivaroxaban once daily from Day 2 until the morning of Day 5, and one single dose of 170 mg VMX-C001 i.v. on Day 5.

LMWH cohort: Subjects will be administered 2 single doses of 40 mg Enoxaparin s.c. on Day 1 and Day 4, and one single dose of 170 mg VMX-C001 i.v. on Day 4.

02

Conditions studied

  • Coagulation Disorder

Browse trials for

Keywords

  • Direct oral anticoagulant (DOAC)
  • Human coagulation factor X
03

In context

Hemostatic Disorders

361 studies on the registry are indexed under Hemostatic Disorders; 65 are open to participants now.

This study's enrollment of 16 is below the median of 60 across 171 interventional studies indexed under Hemostatic Disorders.

Browse Hemostatic Disorders studies →

Lead sponsor

VarmX B.V. is the lead sponsor of 4 studies on the registry; 1 is open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years to 49 Years
Sexes eligible
All
Accepts healthy volunteers
Yes

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  1. Men and women of any ethnic origin aged between 18 and 49 years of age, inclusive, at the time of Screening.
  2. Male subjects must be willing to use appropriate , such as a condom, and to refrain from sperm donation during the main study and until 90 days after study drug administration.
  3. Women of must agree not to attempt to become pregnant and to use a highly effective form of birth control during the main study and for 90 days after study drug administration when their sexual partner has not been vasectomized. Highly effective forms of birth control entail the use of combined (estrogen- and progestogen-containing) or progestogen-only hormonal contraception associated with inhibition of ovulation, an intrauterine device (IUD), an intrauterine hormone-releasing system (IUS) or abstinence.
  4. women must have had ≥12 months of spontaneous amenorrhea (with documented follicle stimulating hormone [FSH] >33.4 IU/L).
  5. Surgically sterile women are defined as those who have had a surgical bilateral oophorectomy with or without hysterectomy, total hysterectomy or tubal ligation at least six weeks before taking study treatment. In case of oophorectomy alone, the reproductive status of the woman has to be confirmed by follow-up hormone level assessment. Women who are surgically sterile must provide documentation of the procedure by an operative report or by ultrasound.
  6. Subject must weigh between 60 and 120 kg, inclusive, and must have a between 18.0 and 30.0 kg/m2, inclusive, at Screening and on Day -1.
  7. Subject must be in good health, as determined by a medical history, physical examination, 12-lead and clinical laboratory evaluations (congenital non hemolytic hyperbilirubinemia is acceptable).
  8. Subject is willing and able to give their written to participate in the study and to abide by the study restrictions.
  9. Subject has good upper limb venous access.

Exclusion criteria

Exclusion Criteria:

  1. The subject has taken tenoxicam in the 35 days prior to Day 1 or has taken piroxicam in the two weeks prior to Day 1.
  2. The subject is receiving or requires, for any cause, any anticoagulant or antiplatelet therapy including warfarin, clopidogrel or aspirin or any other anticoagulant or antiplatelet agent or has used these therapies in the 4 weeks prior to Day 1.
  3. The subject has taken any non-aspirin, non-tenoxicam, non-piroxicam non-steroidal antiinflammatory drug (NSAID) in the week prior to Day 1.
  4. The subject requires or has taken during the 4 weeks prior to Day 1, vitamin K for therapeutic reasons. Vitamin K not taken for therapeutic purposes is acceptable, e.g. as part of a multivitamin supplement.
  5. The subject has received any prescribed oral, systemic or topical medication, including any vaccinations, within 14 days before Day 1 (with the exception of ), unless in the opinion of the Principal Investigator and the Medical Monitor the medication will not interfere with the study procedures or compromise safety.
  6. The subject has used any non-prescribed systemic or topical medication (including herbal remedies) within 4 days prior to Day 1 (with the exception of oral vitamin/mineral supplements [including those that contain vitamin K when not taken for therapeutic purposes] and paracetamol), unless in the opinion of the Principal Investigator and the Medical Monitor the medication will not interfere with the study procedures or compromise safety.
  7. The subject has been administered an drug (new chemical or biological entity) within 4 weeks prior to Day 1 for small molecules or within 12 weeks or 5 halflives, whichever is longer, prior to Day 1 for all other types of investigational drug.
  8. The subject has donated ≥500 mL blood, plasma or in the 12 weeks prior to Screening or the subject has donated any blood amount within 30 days prior to Screening.
  9. Because of an increased risk of thrombosis, subjects with known diabetes mellitus or a fasted glucose ≥7.0 mmol/l at Screening.
  10. The subject has any bleeding diathesis, any increased risk of bleeding or, in the opinion of the Principal Investigator, is at increased risk of the consequences of bleeding including but not limited to the following:

    1. gastro-intestinal ulceration within the last 12 weeks;
    2. known or suspected oesophageal varices;
    3. vascular aneurysms or known arteriovenous malformations;
    4. history of known major intraspinal or intracerebral vascular abnormalities;
    5. history of brain, spinal or ophthalmic surgery within the last year;
    6. any intracranial hemorrhage;
    7. uncontrolled severe hypertension.
  11. The subject has, in the opinion of the Principal Investigator, any increased risk of thrombosis or thromboembolism including any known thrombophilia, such as antiphospholipid syndrome, or any past history of provoked or unprovoked arterial or venous thrombosis, including thromboembolism.
  12. The subject has a significant history of drug allergy, as determined by the Principal Investigator.
  13. The subject has, at Screening or on Day -1, a supine blood pressure or supine pulse rate ≥ 150/95 mmHg and >100 beats per minute (bpm), respectively, or \< 90/40 mmHg and 40 bpm, respectively, confirmed by a repeat assessment.
  14. The subject consumes > 21 alcoholic drinks/week for men or > 14 alcoholic drinks/week for women (one unit of alcohol equals ½ pint [285 mL] of beer or lager, one glass [125 mL] of wine, or 1 measure [25 mL] of spirits), or has a significant history of alcoholism or drug/chemical abuse, as determined by the Principal Investigator.
  15. The subject has a positive drug screen, alcohol test or cotinine test result at Screening or on Day -1, confirmed by repeat testing.
  16. The female subject has a positive pregnancy test at Screening or on Day -1, or is lactating.
  17. The subject currently smokes or uses nicotine-containing products. Former smokers will be eligible, provided they have not smoked for at least 4 weeks prior to administration of the study drug.
  18. The subject has, or has a history of, any neurological, gastrointestinal, renal, hepatic, cardiovascular, psychiatric, respiratory, metabolic, endocrine, hematological or other major disorders, as determined by the Principal Investigator.
  19. The subject has a positive surface antigen (HBsAg), antibody, or (HIV) antibody test result at Screening.
  20. The subject has an abnormality in the 12-lead at Screening or on Day -1 that, in the judgement of the Principal Investigator may, during the main study, interfere with the interpretation of 12-lead ECG results, including average interval >450 msec for men or >470 msec for women, 2nd or 3rd degree atrioventricular block, complete left bundle branch block, complete right bundle branch block or Wolff-Parkinson-White Syndrome, defined as average PR\<110 msec, confirmed by a triplicate repeat ECG.
  21. The subject has any other condition that, in the opinion of the Principal Investigator, would compromise the safety of the subject or the subject's ability to comply with the protocol and complete the study.
  22. The subject has renal insufficiency (serum creatinine level > 1.25 times (ULN) or estimated (eGFR) of \<60 mL/minute*1.73m2 at Screening or on Day -1. One re-test is allowed).
  23. The subject has active liver disease ( [ALT]/ aspartate transaminase [AST] >1.5x ULN, or total > 1.5x ULN at Screening or on Day -1. One re-test is allowed).
  24. The subject has previously participated in a clinical study with VMX-C001.
  25. The subject has any to treatment with heparin (LMWH or UFH).

    Additional exclusion criteria for UFH Cohort only:

  26. Because of an effect on FXa DOACs, subjects are to be excluded if he/she receives or has received medication that is an inhibitor of P-glycoprotein or . (eg clarithromycin, erythromycin and azole-antimycotics such as ketoconazole, itraconazole, voriconazole and posaconazole or HIV protease inhibitors.) within 30 days prior to Day 1.
  27. Because of an effect on FXa DOACs, subjects are to be excluded if he/she receives or has received treatment with CYP3A4 inducers (eg St. John's wort, rifampicin, phenytoin, carbamazepine, phenobarbital within 30 days prior to Day 1.
  28. Because of an effect on FXa DOACs, subjects are to be excluded if he/she receives or has received treatment with selective serotonin reuptake inhibitors (SSRIs) or selective noradrenaline reuptake inhibitors (SNRIs) within 30 days prior to Day 1.
  29. The subject has any contra-indication to treatment with DOACs.
Terms in these criteria, in plain language(19)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Contraception

Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.

Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.

Childbearing potential

Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).

Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.

Postmenopausal

Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).

BMI (body mass index)

Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.

What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.

ECG (electrocardiogram)

A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

Investigational drug or device

A drug or device being studied in a clinical trial.

It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.

Platelets

Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.

Clinically significant

Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.

Hepatitis B tests

Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.

Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.

Hepatitis C tests

Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.

After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.

HIV

The human immunodeficiency virus, which weakens the immune system.

Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.

QT and QTc

On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.

The study may name a correction formula and a limit in milliseconds, often around 450–480.

ULN (upper limit of normal)

The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.

“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.

GFR and eGFR (kidney filtering)

GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².

Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.

ALT and AST (liver enzymes)

Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.

Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.

Bilirubin

A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.

Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.

Contraindication

A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.

CYP3A (CYP3A4) inhibitors and inducers

CYP3A is a group of enzymes, mainly CYP3A4, in the liver and gut that break down many medicines. Some medicines, supplements and foods (grapefruit, St John’s wort) slow them down or speed them up, which changes how much of a study drug stays in the body.

Studies list them so they can be avoided or switched; bring a list of everything you take, including supplements.

05

Study design

Phase
Phase 1
Primary purpose
Treatment
Allocation
Non-randomized
Intervention model
Parallel assignment
Masking
None (open label)
Enrollment
16 participants (actual)

Study arms

  • Experimental
    UFH Cohort

    Subjects will be administered 2 single doses of 5000 IU UFH i.v. on Day 1 and Day 5, oral doses of the DOAC Rivaroxaban QD from Day 2 until the morning of Day 5, and one single dose of 170 mg VMX-C001 i.v. on Day 5.

    Drug: VMX-C001 · Drug: Rivaroxaban · Drug: UFH

  • Experimental
    LMWH Cohort

    Subjects will be administered 2 single doses of 40 mg Enoxaparin s.c. on Day 1 and Day 4, and one single dose of 170 mg VMX-C001 i.v. on Day 4.

    Drug: VMX-C001 · Drug: Enoxaparin

Interventions

  • DrugVMX-C001

    VMX-C001 is human factor X engineered to be insensitive to factor Xa DOACs

  • FXa Inhibitor

  • DrugUFH

    Unfractionated Heparin

  • Low Molecular Weight Heparin

06

What researchers measure

Primary outcomes

  1. Change in thrombin time following dosing with VMX-C001(UFH cohort)

    Change from baseline in thrombin time

    Time frame: Up to Day 6

  2. Change in prothrombin time (PT) following dosing with VMX-C001

    Change from baseline in PT

    Time frame: Up to End of Study (Day 32/33)

  3. Change in activated partial thromboplastin time (aPTT) following dosing with VMX-C001

    Change from baseline in aPTT

    Time frame: Up to End of Study (Day 32/33)

  4. Change in fibrinogen following dosing with VMX-C001

    Change from baseline in fibrinogen

    Time frame: Up to End of Study (Day 32/33)

  5. Change in dilute Russell viper venom time (dRVVT) following dosing with VMX-C001(UFH Cohort only)

    Change from baseline in dRVVT

    Time frame: Up to Day 6

  6. Change in dilute prothrombin time (dPT) following dosing with VMX-C001 (UFH Cohort only)

    Change from baseline in dPT

    Time frame: Up to Day 6

  7. Change in thrombin generation following dosing with VMX-C001

    Change from baseline in thrombin generation measured by calibrated automated thrombography

    Time frame: Up to Day 6

  8. Change in real time activated clotting time (ACT) following dosing with VMX-C001 (UFH cohort only)

    Change from baseline in ACT

    Time frame: Up to Day 6

  9. Change in anti-factor 10a (FXa) activity following dosing with VMX-C001 (LMWH Cohort only)

    Change from baseline in anti-FXa activity

    Time frame: Up to Day 6

07

Study locations

1 site
  • ICON
    Groningen, 9728 NZ, Netherlands
08

References and documents

Individual participant data

Plan to share: No

No publications or documents are linked to this record.

09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on May 11, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT06517563
Lead sponsor
VarmX B.V.
Responsible party
Sponsor
First posted
Jul 24, 2024
Start date
Aug 14, 2024
Primary completion
Dec 9, 2024
Completion
Apr 13, 2026
Last update
May 11, 2026

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is completed, as verified in May 2026. You cannot join it, but the record below documents what was studied.

Follow this study

Get an email when the registry record changes — status, dates, results — or when someone posts here.

Sign in to follow

Discussion

Questions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.

Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.

Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.

Start the discussion