The Need for Titration or Monitoring of Direct Oral Anticoagulant Treatment: The MONDOAC and KIDOAC study

Since its initial discovery in the early 1940s, vitamin K antagonists (VKAs)
have been the cornerstone of anticoagulant treatment. At first developed as a
rodenticide, it became immediately clear that VKAs need to be monitored and
titrated. Direct oral anticoagulant drugs (DOACs) have recently been developed
and marketed to be used in fixed dose regimens without the need for dose
titration or monitoring of blood levels. This is considered to be a substantial
advantage over VKAs. However, it is doubtful as to whether pharmacokinetic
profiles of DOACs are as stable as claimed, that *one size fits all* and that
they do not cause serious clinical events when not correctly used. This is
certainly true for demanding drugs like DOACs, the efficacy of which will be
affected by even one delayed or missed dose. Recently we and others observed
that after starting DOAC for in principal lifelong medication, nearly half of
patients stopped taking their DOAC within 2 years. Why this persistence to DOAC
treatment is so low is currently unknown.

To determine the within and between variability of pharmacokinetic (PK)
profiles in patients treated with DOACs in daily practice

single arm, open label, multicenter clinical trial

In total 60 ml of blood will be collected through veni punction. Veni punction
can be painful en cause a bruise or bleeding at the site of insertion of the
needle