Frequently asked questions
Participating in a clinical study can raise many questions. We have collected and answered the most common ones here.
What does "PFOA II" in "PFOA II study" stand for?
PFOA stand for PatelloFemoral (Osteo)arthrosis. Patellofemoral is made up of the latin terms for kneecap, "patella", and for thigh bone, "femur". PFOA happens when the cartilage in the patellofemoral joint wears away. The patellofemoral joint is located between the kneecap (patella) and the thigh bone (femur). II (=2) indicates that the PFOA II study is a phase II or 2 clinical study. Clinical studies are divided into four phases. In phase I studies, the safety and tolerability of a drug or a therapeutic procedure are tested on a small group of study participants. The PFOA II study was preceded by a phase I study in which the safety and feasibility of the N-TEC procedure (see below "What is N-TEC") were tested. In a Phase II study, the effectiveness and safety of a treatment or drug are tested on a larger group of patients. Sometimes the treatment being tested is compared with an already known therapy (standard therapy). You can find more information about the PFOA II study on the welcome page.
Is it safe to participate in the PFOA II study?
In several studies involving over 60 patients, no serious side effects were observed with this procedure. As with any surgery, side effects can occur, which the doctor will discuss with you in detail before the study. These are mainly pain, bruising and swelling. Joint effusion and swelling can also occur occasionally. Very rarely, wound infections can occur. In the worst case, the transplant does not heal or detaches again. In these cases, if you experience symptoms, another surgery and treatment with standard therapy may be necessary. There are no known dangerous side effects.
Will cartilage removal harm my nose?
We have not yet observed any serious side effects (e.g. deformations, impaired breathing or perforations of the nasal septum) in over 100 people treated. Cartilage removal is only carried out by qualified specialists, i.e. plastic surgeons or ear, nose and throat specialists.
What is N-TEC?
N-TEC is a tissue implant made of cartilage that is grown in the laboratory from the body's own nasal cartilage cells. N-TEC stands for "Nasal chondrocyte Tissue Engineered Cartilage". Nasal chondrocytes, meaning nasal cartilage cells, are similar to the cartilage cells in the knee. They are robust, adapt well to the knee joint and can withstand the loads placed on the knee. To produce the implant, a tiny piece of cartilage is taken from the study participant's/ patient's nasal septum. The removed tissue is then multiplied under strict, sterile conditions in the laboratory and placed on a special material, a so-called collagen membrane, so that it can grow and build cartilage-like tissue. After four weeks, the implant, called N-TEC, is ready and can be inserted. In the operating theatre, the transplant is tailored to the shape and size of the cartilage defect in the knee. Once the damaged cartilage is removed, the N-TEC transplant is inserted into the patient's knee where the cartilage is damaged.
Why can't I have a say in which treatment group I am assigned to?
It is important that the study participants are divided into two groups using an automated random selection process. This is the only way we can obtain reliable results. This process is called "randomization." The study coordinators do not know in advance which group the participants will be divided into. Randomization allows us to assess the results objectively.
What if I am assigned to the standard therapy group but still want to be treated with nasal cartilage tissue?
Basically, we hope that the study will prove that treating kneecap arthrosis with cultured nasal cartilage tissue leads to better results than standard therapy. However, there is currently not enough evidence of this. For an objective assessment of the study results, it is important that the groups are allocated randomly and that the composition of the groups is as balanced as possible. This is the only way we can obtain reliable results. If you are assigned to the group with standard therapy, we would like to ask you to continue to participate in the study as long as you are able. It is not possible to switch from one group to another within the study. Unfortunately, we are currently not allowed to treat anyone with the nasal cartilage tissue outside of the study. If the study produces positive results, we can apply for a temporary permit from the Swiss Medicines Agency Swissmedic, which will allow us to carry out treatment outside of a study. However, this will not be financed by the health insurance companies.
How does the study work and how time-consuming is participation?
1. Checking suitability for the study In order to be able to include you in the study, we check a number of criteria (inclusion and exclusion criteria) and carry out an MRI scan and X-rays. This appointment lasts one to one and a half hours. 2. Treatment Study participants in group 1 (standard therapy) have to come to the hospital three times for an autologous blood injection. Study participants in group 2 (therapy with cultured nasal cartilage transplant) come once for a nasal biopsy. This takes around one and a half hours. After the appointment, you can go home. Four weeks later, the knee surgery (implantation of the cultured tissue) takes place. After that, participants stay in the hospital for 3 to 5 days. They walk with crutches for six weeks and receive physiotherapy for 18 weeks, just like after any other knee surgery. 3. Examinations All participants come to the hospital for four examination appointments. These take place after 6 weeks and after 6, 12 and 24 months. An MRI scan and X-rays are taken at three of these visits, so one to one and a half hours must be planned for these appointments. In addition, all participants are asked to fill out an online questionnaire at 3 different times. It takes about 30 minutes per questionnaire. The questionnaire can be filled out conveniently from home, interrupted at any time and continued again at a later time.
Will I benefit from participating in the study?
You have the chance that your kneecap arthtritis will be treated with a very innovative and promising procedure through this study. However, its effectiveness has not yet been sufficiently proven, which is why we are conducting this study. You may also receive standard therapy. In any case, you will be medically monitored and cared for by highly specialised staff throughout the entire course of the study.
How quickly will I be able to work again or do sports again?
How quickly you can return to work depends largely on your work. You will need to use crutches for 6 weeks. You can do sedentary work during this time, but not other activities. You can start doing light sports like swimming or cycling again after just 3 months. You should not start doing contact sports (e.g. football) again until 12 months later.
Will there be any costs for me if I take part in the study?
There are no costs for you in participating in the study. However, travel costs to the clinic and for the examinations will not be reimbursed. You must cover these yourself. Basic assessments of knee problems, which are usually required before participating in a study, are also not covered.
What if I change my mind and no longer want to participate in the study?
You can stop participating at any time. You do not have to explain why. You will continue to receive your medical treatment even if you stop participating in the study. The data collected up to this point will remain stored and will be evaluated as part of the study.
What happens to my personal data?
There are strict legal regulations in Switzerland to protect personal data, which we adhere to without exception. All data is documented in encrypted form so that it is protected as best as possible against misuse.
