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The feasibility of formulating mini-tablets with 1 mm diameter on a rotary-die press in comparison to mini-tablets of 2 mm was investigated. To gain insight into the production of 1 mm mini-tablets, three model drugs of different compression characteristics were chosen, namely quinine hydrochloride, ibuprofen and spray-dried gentian extract. A high drug load in combination with robust and reproducible mechanical properties was requested. Depending on the individual drug substance, mini-tablets were produced by direct compression or after roll-compaction/dry granulation. The tensile strength, mass, and their variation coefficients were determined to assess the mechanical properties of the tablets. The content uniformity and the dissolution behavior of selected batches were analyzed.For the first time 1 mm mini-tablets could be successfully produced by direct compression (90% quinine hydrochloride; 90% dried gentian extract) and after roll compaction (70% ibuprofen). Depending on the applied compression pressure, 1 mm mini-tablets with quinine hydrochloride exhibited robust mechanical properties (e.g. median tensile strength of 2.02 N/mm2) with equal or lower variance of distribution compared to the 2 mm compacts. With respect to content uniformity of dosage forms, 1 mm mini-tablets containing 80% quinine hydrochloride met the requirements of the European Pharmacopeia (AV = 6.8).