Antibody-coated, drug-eluting stents (AB-DES) feature an exterior coated with immunosuppressant drugs and an interior that is coated with antibodies to accelerate the adhesion of endothelial cells. In theory, this makes it possible to shorten the duration of therapy with blood thinners, which can mean relief for patients from an already difficult situation.
Ms. Fujita-Rohwerder, how do you proceed when you are tasked with inspecting a medical device?
Naomi Fujita-Rohwerder: After receiving the order, we initially work on the so-called report plan. It contains the actual scientific objective meant to be examined during our methodological review. The patient-relevant outcomes for the assessment are specified here for example. In addition, there is a description of the project-specific methodological approach, for instance, as it pertains to data collection. We collaborate with external experts, that is to say, cardiologists and also talk with affected patients. The report plan is published on our web page, initially in a preliminary version. At the same time, we invite public comments (hearings) where everyone has the opportunity to comment on our report plan. The lion’s share of our work pertains to gathering information and subsequent assessment. In the case of the AB-DES project, we also asked the AB-DES manufacturer to provide information on relevant clinical trials in parallel with the bibliographic literature search. In doing so, we were able to conduct our assessment based on previously largely unreleased clinical trial results. Our initial assessment is published as a preliminary report. Once again, there is an opportunity to submit comments directly after publication. After preparing the final report, the conclusive benefit assessment, our work is completed. Unlike the preliminary report, the final report includes the results of the commenting procedure (hearings) as well as possible new clinical trial results.
The stents sound promising and are meant to be further evaluated in clinical studies. Some physicians believe the IQWiG report was published too soon. You also allude to inconclusive data in your final report. Why was the assessment conducted at this stage?
Fujita-Rohwerder: The AK-DES assessment was indeed conducted relatively early compared to other benefit assessments in our area. We already received the assessment request in the fall of 2013, that being the year of market access. Before the AB-DES came on the market, there was another stent that only featured an antibody coating and whose use we already assessed in 2012 – incidentally, 7 years after market access. Compared to the DES, the implantation of an AB stent showed reduced benefit for patients. I am assuming that people wanted to request a prompt respective assessment of the AB-DES due to the negative result. On the one hand, I can definitely understand why there cannot possibly be any results available from major clinical trials this early in the clinical development phase. On the other hand, you might also question whether it is wise to already use this type of new product in everyday healthcare. The AB-DES has not gained market access in other countries like Japan or the U.S. and can only be used within the scope of authorizing necessary clinical trials – incidentally, these clinical trials are the major current studies we mentioned in the final report. The inconclusive data is therefore also the result of the current regulatory framework in Europe.
Will you need to take a second look at the stents?
Fujita-Rohwerder: This is not foreseeable at the present time since the Federal Joint Committee (G-BA) has not reached a final decision about the use of this method under consideration of our benefit assessment results. However, the G‑BA is able to request a repeat assessment at any time, especially if new clinical trial results are available.