Preferences for Risks and Benefits of Islet Cell Transplantation for Persons With Type 1 Diabetes With History of Episodes of Severe Hypoglycemia: A Discrete-Choice Experiment to Inform Regulatory Decisions

Background. The advisory panel for US Food and Drug Administration (FDA) recently endorsed pancreatic islet cell transplantation (ICT) therapy for suboptimally controlled type 1 diabetes (T1D), and FDA approval is under consideration. An important part of regulatory approval includes the patient perspective, through discrete choice. We developed a discrete-choice instrument and used it to determine how 90 people with T1D weigh the risks and benefits of ICT to inform regulatory decisions. Methods. Sawtooth software created a random, full-profile, balanced-overlap experimental design for a measure with 8 attributes of ICT risks/benefits, each with 3 to 5 levels. We asked 18 random task pairs, sociodemographics, diabetes management, and hypoglycemia questions. Analysis was performed using random parameters logistic regression technique. Results. The strongest preference was for avoiding the highest chance (15%) of serious procedure-related complications (beta = -2.03, P < 0.001). The strongest positive preference was for gaining 5-y insulin independence (beta = 1.75, P < 0.001). The desire for 5-y HbA1C-defined clinical treatment success was also strong (beta = 1.39, P < 0.001). Subgroup analysis suggested strong gender differences with women showing much higher preferences for all benefits (68% higher for 5-y insulin independence), and men were generally more risk averse than women. Those with high versus low diabetes distress showed 3 times stronger preference for 5-y insulin independence but also twice preference to avoid risks of serious complications. Conclusions. Despite showing the most preference for avoiding serious ICT complications, people with T1D had a strong preference for achieving ICT benefits, especially insulin independence. We identified important attributes of ICT and demonstrated that patients are willing to make these trade-offs, showing support for the introduction of ICT.

Automated summary

This study investigated the preferences of 90 type 1 diabetes patients for the risks and benefits of pancreatic islet cell transplantation (ICT) therapy through a discrete choice instrument. The results showed that patients had the strongest preference for avoiding serious complications, while also strongly desiring insulin independence and clinical treatment success.