Treatment intensification strategies in type 2 diabetes mellitus (T2DM) often require evaluation across diverse patient profiles to guide clinical decision-making. A prespecified subgroup analysis of the phase IV, randomized, open-label, active-controlled SURPASS-SWITCH trial, published in BMJ Open Diabetes Research & Care, assessed the efficacy and safety of switching from dulaglutide to tirzepatide in adults with T2DM across multiple baseline characteristics.

Adults with glycated hemoglobin (HbA1c) between ≥7.0% and ≤9.5%, on stable dulaglutide therapy for at least 6 months and stable oral antihyperglycemic therapy for at least 3 months, were randomized 1:1 to either continue dulaglutide with escalation to 4.5 mg or maximum tolerated dose or switch to tirzepatide with escalation to 15 mg or maximum tolerated dose. Outcomes included changes in HbA1c and body weight at week 40 across predefined subgroups, including age, baseline HbA1c, duration of diabetes, dulaglutide dose and duration, body mass index (BMI), ethnicity, and sex.

Reductions in HbA1c and body weight at week 40 were significantly greater with tirzepatide compared with dulaglutide across all prespecified subgroups. Greater HbA1c reduction was observed in participants with higher baseline HbA1c and lower BMI. Weight reduction was more pronounced in non-Hispanic or non-Latino participants. Safety profiles were similar across groups, with nausea and diarrhea reported most frequently as treatment-emergent adverse events.

These findings indicate that switching from dulaglutide to tirzepatide is associated with consistent improvements in glycemic control and body weight across a range of baseline characteristics, with a similar safety profile across subgroups.