Long acting parenteral formulations are preferred over conventional formulations for the treatment of chronic diseases. Prevalence of such diseases provoked the interest of researchers and pharmaceutical industries in the development of long acting parenteral formulations. The regulatory guidelines and pharmacopoeia have remained silent on dissolution methods for long acting parenteral formulations due to their diverse nature. The lack of compendial method for dissolution testing increases the duration of approval process for long acting parenteral formulations. This article reviews various dissolution methods used to study in vitro drug release profile of long acting parenteral formulations. Compendial as well as noncompendial methods, such as- rotating dialysis cell, dialysis tube, rotating bottle, shaking flask, single drop, inverted cup and incubation, are used by researchers for drug release profile of long acting parenteral formulations. This review article also highlights the advantages and disadvantages of reported dissolution methods along with the suitability of these methods for particular type of long acting formulation. The compiled work will help the researchers in designing the biorelevant dissolution method and expedite the development of long acting parenteral formulations.

Overexpression of the gonadotropin-releasing hormone receptor (GnRH-R) plays a vital role in the advancement of reproductive malignancies such as ovarian, endometrial, and prostate cancer. Peptidomimetic GnRH antagonists are a substantial therapeutic development, providing fast and reversible suppression of gonadotropins by directly blocking GnRH-R. Unlike typical GnRH agonists, these antagonists prevent the early hormonal flare, have a faster onset of action, and have a lower risk of cardiovascular problems. These characteristics qualify GnRH antagonists as revolutionary therapy for diseases such as advanced prostate cancer, endometriosis, uterine fibroids, and in vitro fertilization procedures. Key GnRH peptide antagonists authorized by the regulatory agencies include Cetrorelix, Ganirelix, Abarelix, Degarelix, and Teverelix. Assisted reproductive technologies (ART) are dominated by Cetrorelix and Ganirelix, while Degarelix and Abarelix have shown significant promise in treating advanced prostate cancer. Teverelix appears as a next-generation GnRH antagonist with an ideal mix of efficacy and safety, showing promise in a variety of reproductive and hormone-dependent illnesses. This review investigates the pharmacological role of GnRH in reproductive physiology and its consequences in disease, emphasizing structural advances in third- and fourth-generation GnRH antagonists. All GnRH peptide-based antagonists were analyzed in detail for formulation strategy, pharmacokinetics, effectiveness, and safety. This review also emphasizes GnRH antagonists’ clinical promise, providing insights into their evolution and the possibility for future research in developing safer, more effective treatments for complicated hormonal diseases.