In situ forming depot (ISFD) long-acting injectables (LAI) are liquid formulations that form a drug reservoir upon contact with an aqueous environment, such as subcutaneous tissue or specific local delivery sites. These bioresorbable systems offer minimally invasive administration and customizable release profiles, making them suitable for various therapeutic areas, including central nervous system disorders, oncology, or pain management, to name a few. BEPO® technology, utilizing polyethylene glycol-polyester block copolymers in an organic solvent like DMSO, stands out as ISFD LAI for its flexibility in release kinetics and duration, ranging from days to 1 year. The versatility of BEPO® extends to both intraarticular and systemic administrations, with the ability to modulate drug release kinetics by adjusting formulation parameters. This adaptability allows for the sustained release of small molecules, peptides, and macromolecules over periods from days to months, addressing chronic conditions requiring consistent therapeutic levels. Preclinical studies have confirmed the biocompatibility and safety of BEPO® formulations, particularly when using DMSO as an excipient. Products like Uzedy®, a long-acting injectable of risperidone for schizophrenia, and ongoing clinical trials for olanzapine and celecoxib formulations, demonstrate its clinical potential. The future of BEPO® technology looks promising with the development of BEPO® Star, which utilizes branched polyethylene glycol-polyester copolymers for enhanced release control and injectability, potentially expanding its applications across various medical fields.