In-depth interviews of patients with primary immunodeficiency who have experienced pump and rapid push subcutaneous infusions of immunoglobulins reveal new insights on their preference and expectations

Purpose: Patients with primary immunodeficiency (PID) often receive immunoglobulin replacement therapy (IgRT). Physicians and patients have the choice between various methods of administration. For subcutaneous immunoglobulin infusions, patients may use an automated pump (P) or push the plunger of a syringe (rapid push [RP]). P infusions are performed once a week and last around 1 hour. RP decreases the duration of administration, but requires more frequent infusions.

Patients and methods: Eight out of 30 patients (coming from a single center) who had participated in the cross-over, randomized, open-label trial comparing P and RP participated in a focus group or underwent in-depth interviews. Patients had a long history of home-based subcutaneous immunoglobulin using P. The trial suggested that RP had slightly greater interference on daily life than P, but similar efficacy and better cost-effectiveness. When asked about the delivery method they had preferred, around one-third of patients pointed out RP rather than P. In-depth interviews may reveal unforeseen reasons for patients' preferences.

Results: Interviews underlined the complexity of the relationship that the patients maintain with their disease and IgRT. Even if they recognized the genetic nature of the disease and claimed PID was a part of them, patients tried not to be overwhelmed by the disease. IgRT by P was well integrated in patients' routine. By contrast, RP too frequently reminded the patients of their disease. In addition, some patients pointed out the difficulty of pushing the plunger due to the viscosity of the product. Coming back too frequently, RP was not perceived as time saving over a week. Long-lasting use of P could partly explain patients' reasonable reluctance to change to RP.

Conclusion: In-depth interviews of PID patients highlighted unforeseen reasons for patients' preference that the physician needs to explore during the shared medical decision-making process.