Table 3.

Concerns.

SUB-THEMES	ARGUMENTS	QUOTATIONS
Safety and effectiveness	•Safety concerns for early-phase clinical trial participants •Safety concerns regarding the use of scaffolds, genetically modified cells and pig islets. •Worries about the BAP producing excessive or insufficient insulin •Need for re-transplantation •Concerns about the removability of the BAP in the event of malfunction •The potential requirement for immunosuppressive medication	‘’If you put it in a scaffold, you can also remove it [the BAP] out of the body. What I am really afraid of, of course, is that the scaffold will leak and that those genetically modified cells can get into the person [with type 1 diabetes], we do not know what will happen then. I mean when genetically modified cells will be used. In practice these cells could become cancer cells, and I think that is a bit scary. You can also imagine that the cancer can grow in the scaffold and grows out of it, right. So yes, then you can say that the layer can protect it. But when it is an aggressive cancer, I can also imagine that it just goes straight through it.’’ − Professional 12 ‘’You can always say beforehand: ‘Yes, we don’t know if it works for you… and if it does work, I don’t know how long it will work’… But eventually, they will be confronted with it if it turns out to work for a shorter time than they hoped, or it [the BAP] did not work at all… Yes, that uncertainty, yes, that would be a concern for me. However, it wouldn’t be a reason not to investigate it, let that be clear.‘’ − Professional 17
Inequitable access	•Concerns about excessive developmental costs, the lack of universal reimbursement policies, and resource scarcity	‘’I am concerned that people may end up paying for it [the BAP] themselves, and going directly to the company where it is manufactured, once the BAP is likely commercialized. As a result, only those with substantial funds would have access to it. That is something that plays out in healthcare anyway. In the Netherlands, it is less severe than in the United States for instance, but even here in The Netherlands, people who are poor or have a migration background receive worse care simply, because they have less money and fewer resources. The most significant predictor in the Netherlands for good health is high socio-economic status, and that will also come in play with the BAP. You see that with many novel technologies, that nice new interventions actually increase inequality because they are only available to a portion of the population.’’ – Professional 12 “If you have everything under control, your diabetes is well managed, you work hard, and it leads to perfect regulation, then you are currently being punished, because you won’t qualify for new treatment, because you are doing too well, that is how it feels for them, I can imagine.’’ − Professional 6
Provision of accurate information	•Concerns about comprehensively explaining all relevant risk •Worries that inflated hopes for a cure may impair individuals’ ability to assess risks and benefits, and anticipate the potential impact of a BAP transplant on their lives	‘’Then there is another press release in the newspaper about a new therapy successfully transplanted into some mouse, and the next day they [persons with type 1 diabetes] are in my office asking, ‘Did you see that, and when will it be available for people?’’…Well, I think that there is too much hope being offered, like, we are almost there, well definitely not. That is frustrating for people. Like I said, there are people who have hundred thousand euros in the bank for years, to be able to get a transplant. That is quite demotivating for people.‘’ – Professional 13 “I tell people in my clinic that they should focus on the [medical device] technology, because that will help them the most in the upcoming years. It will take at least 10 years before diabetes is cured, so do not hope for that.” – Professional 6
Relinquishing control	•Concerns that sudden loss of control over blood glucose levels could lead to stress for recipients •Worries that excessive reliance on BAP’s functionality may diminish self-management skills over time	“You undergo the surgery, and afterwards, the glucose levels are consistently normal, they [persons with type 1 diabetes] find that hard to believe because they are very addicted to check their blood glucose levels constantly.’’ − Professional 8 “If you are used to doing a lot self-management and suddenly that disappears, then there is a huge emptiness. How will they fill that emptiness? That is really, yes, that is really something. Psychological support is definitely needed.’’ – Professional 4
Organizational challenges	•Concerns that unclear attributions of responsibilities and ineffective multidisciplinary collaboration across disciplines could hinder implementation	‘’The conditions and responsibilities must be clearly defined. It may turn out that another team is responsible for the BAP, and perhaps we would not have any role anymore. That is entirely possible. We must prevent people from falling through the cracks, because their diabetes is resolved, ensuring they continue to be monitored in some way. We must ensure they don’t disappear from view.’’ – Professional 4 ‘’I am concerned whether people [with a BAP] can act accurately in case of an emergency. What if something goes wrong [with the BAP] and the sugar becomes disrupted? You want to prevent them [ individuals with a BAP] from ending up in the ICU with a ketoacidosis. They need to be able to recognize signals, and we need to continue repeating and educating them that.’’ – Professional 16