The present disclosure relates generally to drug delivery systems and related methods of use. The drug delivery systems can include one or more particles, each of which can include a biologically active compound dispersed therein. The drug delivery systems can also be configured to exhibit zero-order or near-zero-order release of the biologically active compound. The particles can be cylindrical or rod-like in shape, and can include a polymeric inner matrix having a biologically active compound dispersed therein, and a polymeric outer layer disposed at least partially around the inner matrix.