Current modalities for osteoarthritis (OA) treatment are partially safe and effective, and only alleviate the disease symptomatology, but do not modify progression and structural changes of the disease. At present, there is no approved safe and effective disease-modifying OA drug (DMOAD) for clinical application. Therefore, there is an urgent need for discovery of DMOAD in order to treat OA. Hopefully, the new DMOADs would also pave the way for better understanding of OA pathophysiology. Given the fact that there is still no adequate remedy that will modify the course of OA, a number of emerging pathways and promising agents with possible DMOAD effect arise targeting cartilage, synovial membrane, and subchondral bone, or using stem cell therapy, and gene therapy. All these methodologies will be described and discussed in this review. Available treatment methodologies for OA are unsatisfactory. In order to properly treat OA in the future, more realistic option will be the use of multiple drugs, instead of single therapy, which is likely to be ineffective in the treatment of such heterogeneous diseases. Which combination of drugs with DMOAD effect will be suitable for the treatment of OA, remains to be determined in future studies.