An update on microneedle in insulin delivery: Quality attributes, clinical status and challenges for clinical translation

Diabetes mellitus is a significant chronic illness and a major community health issue caused by a glucose metabolic imbalance. Insulin therapy is required for patients with type 1 and type 2 diabetes mellitus. The most frequent form of administration is still subcutaneous injection. Non-invasive insulin administration solutions are being researched because they have the potential to reduce discomfort, anxiety, and distress in patients. The majority of glucose sensing modalities and most insulin therapy entail the transference of physical constituents through the skin. In such a pursuit, microneedles can accomplish the stated requirement in a painless or less invasive approach while also affording a myriad of other technical benefits. A better comprehension of the human skin, its fundamental architecture as a polymeric film, and its significance as a functional biological unit are thus mandated for the iterative design of a non-invasive, bioengineered delivery system such as microneedles. The quality attributes of the microneedle fabrication necessitate the development and approval of critical assessment and evaluation methodologies. The present review elaborates upon the application of microneedles for the suitable delivery of insulin. The existing usability, needful quality attributes, along with the challenges associated with the manufacture and/scale-up, clinical translation, and regulatory clearance, are also discussed. Also included is a brief statement on the current clinical status of the microneedles-based insulin delivery system. [Display omitted]