PATIENT TREATMENT PREFERENCES AMONG JAPANESE PATIENTS WITH CHRONIC GLOMERULONEPHRITIS：DISCRETE CHOICE EXPERIMENT

For chronic glomerulonephritis, including IgA nephropathy(IgAN), novel drugs have been developed in recent years. As treatment options diversify, a treatment strategy developed with consideration of patients’ preferences may lead to improvements in treatment satisfaction and clinical outcomes. The objective was to identify the treatment preference for chronic glomerulonephritis, which has not been previously reported in Japan.

The present survey was conducted as a web-based questionnaire survey using the discrete choice experiment (DCE) approach. Eligibility criteria for this survey were patients who had been diagnosed with chronic glomerulonephritis using a kidney biopsy and who had not undergone dialysis. The attributes and levels were based on literature review, the results of clinical trials of chronic glomerulonephritis treatments, and the expert opinion. The following attributes were set in DCE: “treatment effect on eGFR”, “period of confirmed safety”, “administration method and frequency” and “copayment at the reception”. The survey was conducted with patients who met the eligibility criteria and consented to participate in the survey. The strength of preference between the levels of each attribute was evaluated using preference weight. The contribution of each attribute to treatment preference was evaluated using relative importance.

The survey included 286 participants, with a mean age of 55.7 years. IgAN was the most common type of chronic glomerulonephritis currently being treated, accounting for 187 participants (65.4%). Of these, 84 had undergone tonsillectomy. Among 103 patients with IgAN who had not undergone tonsillectomy, 77 stated that they would prefer to try medication rather than surgery. Of the 49 patients with IgAN who responded that they were currently receiving steroid treatment, 10 patients responded that they did not want to continue taking steroids, and 22 patients responded that they would be willing to switch if a novel treatment were launched. Additionally, a survey revealed that 92.0% of patients with chronic glomerulonephritis proactively desired to receive information from their physicians about novel treatments upon their launch. When selecting a novel treatment for chronic glomerulonephritis, the most important treatment attribute was “treatment effect on eGFR”, followed by “copayment at the reception" and “administration method and frequency". Patients showed a stronger preference for oral formulations taken once or twice daily than for injectable formulations administered once or twice weekly or monthly. Among patients covered by public medical expense subsidy program, “administration method and frequency” was the second most important attribute after “treatment effect on eGFR”.

The observed preferences for existing treatments and need for information about new drugs suggest a strong patient demand for novel therapeutic options. Our findings suggest that for novel treatments, patients prefer non-invasive oral formulations with a high treatment effect on eGFR and a low copayment. Differences of preferences observed in the subgroup analysis suggest the need for individualized treatment selection. These results can be used to inform patient-centered treatment plans when novel chronic glomerulonephritis treatments are launched in Japan in the future.