Who can participate in the study?

All renal cell carcinoma patients who are currently being treated with axitinib or cabozantinib, or who are about to start treatment with axitinib or cabozantinib, can participate in the study. Your treating physician will decide together with you whether you are eligible to participate in the study.

What does the study participation require from me?

To allow us to interpret the measured drug concentrations in the best possible way, it is important to know when you took your medicines in the month before the measurement. Therefore, we ask you to document your intake in a diary provided by us. If you wish, you can also enter other notes related to your drug therapy in the diary. At the end of the diary, you will find a questionnaire about the adverse drug reactions you have experienced (it will take no more than 5 minutes to complete the questionnaire). As soon as the diary is full at the end of the month, we ask you to send it to us in a prepaid envelope. Your treating study center will then hand you a new diary. If you collect a blood sample yourself at home during the second study phase, we will also ask you to complete a short questionnaire about your experience with at-home sample collection.

Does my doctor see the questionnaires regarding adverse drug reaction and sample collection filled out by me?

No, the questionnaires can only be viewed by the study staff for data evaluation. As usual, your treating physician will ask you about any adverse drug reactions you experience during your routine visit and, if necessary, adjust your therapy, taking into account the drug concentrations measured during therapeutic drug monitoring.

When can I perform the minimally invasive blood collection myself at home?

In order for us to compare the concentrations measured in capillary blood with the target concentrations defined for venous blood, a conversion factor must be determined. For this purpose, if you agree, both a venous blood sample and a VAMS sample will be taken from you in the doctor's office at the first appointment. The practice staff will show you exactly how the sample is taken. At the next appointment, a venous blood sample will be taken from you and we will ask you to take the VAMS sample yourself under the guidance of the practice staff. As soon as the conversion factor has been determined (for this we need a total of approx. 40 sample pairs or 2 sample pairs per patient), the blood sample can be taken at home.

Do I have to perform the blood collection myself in the secondary phase or can I continue to come to the doctor's office for it?

Of course, you can come to the doctor's office for blood collection throughout the whole course of the study.

How long will the study participation be for me?

There is no minimum duration of study participation. The decision for how long you participate in the study is solely up to you and your treating physician, and is based on the frequency and severity of adverse drug reactions you experience. The maximum study participation is equal to the total study duration and is 2 years.