There has been a constant evolution in the pharmaceutical market concerning the new technologies imbibed in delivering drug substances for various indications. This is either market-driven or technology-driven to improve the overall therapeutic efficacy and patients’ quality of life. The pharmaceutical industry has experienced rapid growth in the area of complex injectable products because of their effectiveness in the unmet market. These novel parenteral products, viz, the nanoparticles, liposomes, microspheres, suspensions, and emulsions, have proven their worth as “Safe and Effective” products. However, the underlying challenges involved in the development, scalability, and characterization of these injectable products are critical. Moreover, the guidelines available do not provide a clear understanding of these complex products, making it difficult to anticipate the regulatory requirements. Thus, it becomes imperative to comprehend the criticalities and develop an understanding of these products. This review discusses various complexities involved in the parenteral products such as complex drug substances, excipients, dosage forms, drug administration devices like pre-filled syringes and injector pens, and its different characterization tools and techniques. The review also provides a brief discussion on the regulatory aspects and associated hurdles with other parenteral products.

Graphical abstract

中文翻译：

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复杂注射产品的视野不断扩大：开发和监管方面的考虑

制药市场一直在不断发展，涉及为各种适应症输送药物的新技术。这要么是市场驱动，要么是技术驱动，以提高整体治疗效果和患者的生活质量。由于复杂注射剂产品在未满足的市场中的有效性，制药行业在复杂注射剂产品领域经历了快速增长。这些新型注射用产品，即纳米颗粒、脂质体、微球、悬浮液和乳剂，已证明其作为“安全有效”产品的价值。然而，这些可注射产品的开发、可扩展性和表征所涉及的潜在挑战至关重要。此外，可用的指南并未提供对这些复杂产品的清晰理解，很难预测监管要求。因此，理解关键因素并加深对这些产品的理解变得势在必行。本综述讨论了肠胃外产品中涉及的各种复杂性，例如复杂的原料药、赋形剂、剂型、给药装置（如预装注射器和注射笔）及其不同的表征工具和技术。该评论还简要讨论了监管方面以及与其他肠外产品相关的障碍。预装注射器和注射笔等药物管理设备及其不同的表征工具和技术。该评论还简要讨论了监管方面以及与其他肠外产品相关的障碍。预装注射器和注射笔等药物管理设备及其不同的表征工具和技术。该评论还简要讨论了监管方面以及与其他肠外产品相关的障碍。

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