Testing on animals is expensive, ethically controversial, and poorly predictive of the response in humans. Conventional two-dimensional (2D) cellular assays do not accurately reflect the drug response in vivo. To overcome these limitations, biotechnologists are developing three-dimensional (3D) cultures. 3D cultures provide more accurate compound screening and can eliminate toxic and ineffective substances at an early stage. Moreover, 3D cultures can accomplish the 3R agenda (refinement, reduction, and replacement) for the replacement of toxicity testing on animals. We provide an up-to-date overview on the patents in the field.