Gastrointestinal adverse events remain a key limitation of incretin-based therapies for type 2 diabetes mellitus (T2DM). A dose-response analysis published in Diabetes, Obesity and Metabolism evaluated whether structured dose-escalation regimens influence tolerance to nausea and vomiting among individuals treated with glucagon-like peptide-1 receptor agonists and the dual glucose-dependent insulinotropic polypeptide/glucagon-like peptide-1 receptor agonist tirzepatide.

The analysis examined Phase 1 trials, which involved no or short dose escalation, and Phase 3 trials that incorporated formal dose-escalation protocols. Non-linear regression modeling was used to estimate the dose required to elicit nausea or vomiting in 50% of exposed participants (ED50). The ratio of ED50 values derived from Phase 3 versus Phase 1 trials was used as an indicator of tolerance development.

For semaglutide, administered subcutaneously and orally, and for tirzepatide, the ED50 ratio (Phase 3/Phase 1) for nausea and vomiting was significantly greater than 1, indicating higher tolerated doses following escalation protocols. Across approved incretin-based therapies, higher ED50 ratios were associated with longer escalation periods and a greater number of dose-escalation steps. The ED50 ratio was also significantly associated with reductions in hemoglobin A1c (HbA1c) and body weight observed in clinical trials.

These findings suggest that structured dose-escalation regimens are associated with greater tolerance to gastrointestinal adverse events and permit the use of higher therapeutic doses in clinical development programs.