Normally, people with high blood pressure are given medication to lower their blood pressure; there are several medications that can do this. We just don't know which medication works well because it varies from person to person. This is why people with high blood pressure often have to take several medications before finding one that works well. In our research, we therefore want to see whether we can predict the effect of the medication on blood pressure using certain tests in the blood and urine. The drugs we are investigating are already prescribed by doctors.
Aim of the study
In this study, we are investigating whether we can predict how well medication to treat high blood pressure will work for a particular person. The drugs we will be testing are: Olmesartan, amlodipine, hydrochlorothiazide and a combination of olmesartan and amlodipine.
Who can take part?
Patients aged 18 to 75 years who were diagnosed with high blood pressure and who were using no or only one antihypertensive drug.
Without medication, the systolic blood pressure is 130-164 mmHg in the 24-hour blood pressure measurement.
Procedure
The drugs that we will test in this study are:
- Imesartan medoxomil (=olmesartan), 40 mg, 1 x daily, orally,
Glenmark
- Amlodipine, 10 mg, 1 x daily, oral, Sandoz
- Hydrochlorothiazide, 25 mg, 1 x daily, oral, Mylan
- Olmesartan medoxomil / amlodipine (combination preparation), 20 mg/5 mg, 1 x daily, oral, Aurobindo
In this study, there are three different treatment phases in which you will receive a total of three of the above four medications. Neither you nor the study team will know which of these drugs you will take in which treatment phase. However, if it is important for your health, this can be verified.
We collect, use and store medical data relevant to the study as well as blood and urine samples from you.
Due to the gender-independent effect of the medication used, no gender-dependent dosages are planned for the participants.
Step 1: Are you suitable for participation?
First of all, we would like to know whether you are suitable to participate in the study. The study team is therefore carrying out a series of tests:
- A physical examination: For example, the study doctor will listen to your heart and lungs and measure your heart rate.
- 24-hour blood pressure measurement: You receive a blood pressure monitor that you wear for 24 hours.
- Blood test: A member of the study team will take 20 ml of blood from you (equivalent to about 2 tablespoons). We test the blood for salts, kidney function and liver values. We will let you know if you have abnormal results.
- Urine test: For this you collect urine. We test the urine for protein levels and, if necessary, for pregnancy. We will let you know if you have an abnormal result.
- Electrocardiogram (ECG): an ECG records the heart currents and indicates structural heart damage.
- Medical history survey: insight into your medical history and medication intake. In this study, ethnicity is recorded. The reason for this is that it must be clear afterwards which ethnic origin the test subjects had so that you can make a statement about which people the study results are valid for.
- Duration of the examination appointment: approx. two hours.
Step 2: the treatment
We will treat you with study medication three times for 4 weeks. During the treatment phase, you will take one capsule of the study drug per day. If you forget to take your medication in the morning, you can take it during the course of the day.
After the respective treatment phase, you will be asked to return the remaining study medication and the empty medication packs to the study center.
In each treatment period of 4 weeks, you will receive a different medication or a different combination of medications. There are two weeks between the blocks during which you do not take any study medication.
The lot decides which 3 medicines you will receive. Neither you nor the study team will know which group you are in. However, if it is important for your health, this can be verified.
Step 3: Investigations and measurements
You have to come to the hospital 10 times within 16 weeks for the examinations. The examinations at the beginning and end of a treatment period (6 times in total) take the same amount of time.
On the examination date (visits 2, 3, 4, 5, 6, 7) we carry out the following:
Interview with the study team
Examination of your blood: The examiner will take 30 ml of blood from you at a time (this corresponds to about 3 tablespoons).
The following things are determined from the blood:
- Baseline blood values of: Electrolytes, kidney values, blood lipid values, protein.
- How did the medication work?
- In this study, your blood and urine are examined for biomarkers (proteins, hormones, genes). By combining the results of these tests, a so-called biomarker profile can be created. We use this biomarker profile to try to predict the response to the medication.
- Some of the blood is analyzed directly in the local laboratory and some is analyzed later in an external laboratory.
24-hour blood pressure measurement:
You will receive a device from us that measures your blood pressure over 24 hours. After this measurement period, you can remove the device yourself and bring it with you to your next appointment. We then evaluate this.
24-hour urine collection:
- To do this, you collect your urine for 24 hours before the respective visit. We have provided you with a brown collection container with a yellow lid for this purpose.
- On the day you start, the first morning urine still goes into the toilet. All the urine is then collected until the next morning - this time including the first morning urine.
- Please store the container in a cool and light-protected place during and after collection.
- If the container is not sufficient, please also use a suitable and clean container (e.g. water/PET bottle etc.).
- Please bring the complete urine collection with you to your next appointment.
- We use urinalysis to test your biomarker profile and whether you have taken the medication.
Urine sample (only for visits 3, 5, 7):
Values are determined here to rule out possible side effects of the medication.
Questionnaires:
They will fill out questionnaires. The questions relate to your quality of life and any side effects of the medication.
Duration of each visit: approx. 1 ½ hours.
Approximately 7 days after the start of each treatment period (three times in total), you will have further blood tests carried out (blood samples A, B and C, see detailed schedule below). A 20 ml blood sample will be taken and examined for possible side effects of the medication. These examinations are carried out at the study center. Duration approx. 15 minutes.
In the overview below you will find all procedures for each date. There are two or four weeks between the screening and the start of the first treatment period. This depends on the medication you are currently taking.
Compensation
There are no additional costs for you or your health insurance company for participating in the study. Travel expenses incurred as a result of participation in the study will be reimbursed up to a maximum of CHF 200 for the entire study participation upon presentation of the Q
Original study name
Multi-Omics to predict the blood pressure response to antihypertensives
BASEC number
2023-02274
Sponsors
This study is mainly financed by the European Union. In Switzerland, the study is funded by the federal government.