Multidrug co-crystals: towards the development of effective therapeutic hybrids.

Co-crystals have garnered the interest of the pharmaceutical industry with the introduction of regulatory guidelines by the US Food and Drug Administration (FDA) as a result of expanded patent portfolios. The Phase II clinical success of tramadol and celecoxib co-crystal for the treatment of acute pain followed by a recent reflection paper published by the European Medicines Agency (EMA) have further boosted the development of drug-drug co-crystals. Here, we shed light on the developments of drug-drug co-crystals and highlight future perspectives for exploring new therapeutic hybrids deploying drug-drug, drug-nutraceuticals and drug-inorganic salt combinations with improved pharmaceutical and biopharmaceutical performance.