There are two parts of the study. In Part 1, the invesitgaotrs want to investigate whether treatment with apixaban improves pain and quality of life in patients with painful venous malformations The participants are randomized to different treatment orders of the two treatment periods with apixaban and placebo. Arm 1 starts apixaban followed by placebo and arm 2 starts with placebo followed by apixaban. Between the treatment sequences there will be a washout period of minimum one week. The participants will register pain and use og pain medication in a diary every day for one week before start of treatment and before evaluation of effect. Also, a quality of life form will be filled out before each consultation. In Part 2, the investigators will investigate long-term effect and safety of apixaban and reduce dose after 3 months to find the minimal effective dose. Part 2 includes participants from Part 1 study who experienced effect of treatment or who agree to continue apixaban treatment. Study start of Part 2 is at the end of Part 1. All participants receive the same dose of apixaban as in part 1 (5 mg twice daily), and after 3 months (visit 2) the dose is reduced to 2.5 mg twice daily.
There are no established universal guidelines on the hematologic management of patients with venous malformations (VM) with and without localized intravascular coagulopathy (LIC). Anticoagulation treatment with low molecular weight heparin (LMWH) has improved functionality and decreased pain in patients with VM with localized LIC. The aim is to study the effect of the direct oral anticoagulant apixaban in patients with painful venous malformations with localized intravascular coagulation. Apixaban is an oral direct acting anticoagulant shown to be as effective and safe as LMWH and warfarin in treating venous thrombosis. single-center, prospective double-blind crossover superiority study including patients with venous malformations at age 18-85 years. The participants are randomized to different treatment orders of the two treatment periods with apixaban and placebo. Masking of participants and study personell. Randomization at screening to arm 1 or arm 2. Arm 1 starts apixaban followed by placebo and arm 2 starts with placebo followed by apixaban. Between the treatment sequences there will be a washout period of one week. Part 2: The AVA Long study is an open-label observational study including participants from the AVA study who experienced effect of treatment or who agree to continue apixaban treatment. Study start of AVA long (part 2) is at study end of part 1. The participants receive the dose of apixaban as in part 1 (5 mg twice daily), but open-label, and after 3 months (visit 2) the dose is reduced to 2.5 mg twice daily. The investigators will investigate long-term efficacy and safety of apixaban and find the minimal effective dose.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
TREATMENT
Masking
QUADRUPLE
Enrollment
20
5 mg twice daily
placebo twice daily
Oslo University Hospital
Oslo, Norway
Difference between apixaban and placebo in change of self-reported pain intensity before and 8 weeks after starting treatment Change in type, dose and frequency of pain medication
Average numeric rating scale (NRS) score(score 0-10 where 0 represents no pain and 10 represents worst imaginable pain) last 7 days before assessment
Time frame: From enrollment to the end of treatment at 8 and 17 weeks
Change in pain medication
Registration of type, dose and frequency of pain medication last 7 days before assessment
Time frame: From enrollment to the end of treatment at 8 and 17 weeks
Difference between apixaban and placebo in change of quality of life before and 8 weeks after starting treatment
Outcome Measure for Vascular Malformation (OVAMA) questionnaire
Time frame: From enrollment until end of treatment, at 8 and 17 weeks
Difference between apixaban and placebo in change of quality of life before and 8 weeks after starting treatment
Short form survey-36 (SF-36)
Time frame: From enrollment until end of treatment, at 8 and 17 weeks]
Difference between apixaban and placebo in change in coagulation parameters before and 8 weeks after
D-dimer
Time frame: From enrollment until after end of treatment at 8 and 17 weeks
Change in pain intensity after 3 months treatment
Numeric rating scale (NRS) score at time of evaluation (score 0-10 where 0 represents no pain and 10 represents worst imaginable pain)
Time frame: From enrollment of Part 2 until completion of treatment at 6 months
Change in pain intensity three months after reducing dose
Numeric rating scale (NRS) score at time of evaluation (score 0-10 where 0 represents no pain and 10 represents worst imaginable pain)
Time frame: At changing dose at 3 months after enrollment of Part 2 and after 6 months ( end of treatment)
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.