Strategies for inhibiting the burst release effect in peptide long-acting release delivery systems

Peptide medications are essential for the treatment of numerous illnesses and offer several benefits, including minimal toxicity and excellent specificity. Nevertheless, issues including peptide medicines' short in vivo half-life and poor oral bioavailability have significantly restricted the clinical use of many peptide medications with lengthy therapy cycles. Extended single injection cycles and fewer injections are possible with long-acting formulations. In situ gel and microsphere formulations are among the most promising for the long-acting administration of peptide drugs; however, the burst release effect that occurs during the initial stage of administration of these two formulations may raise the risk of adverse drug reactions, making this a critical problem that requires immediate attention. With the goal of providing a thorough theoretical foundation and useful advice for the optimization of the performance of these two types of long-acting injections, as well as encouraging the advancement of the technology of long-acting administration of peptide drugs, this paper examines the causes of the burst release effect of in situ gel and microsphere formulations from the physicochemical properties of peptide drugs, polymer matrix, solvent, and preparation process, among other aspects. Additionally, it seeks to increase patient drug compliance and the effectiveness of peptide medications.