New liquid oral formulations of hydroxychloroquine: a physicochemical stability study

Abstract Objectives Hydroxychloroquine (HCQ) presents many drug properties that increase its therapeutic use. There are, indeed, different research pathways in numerous autoimmune, inflammatory, and infectious diseases, as well as in cancerology. HCQ is only marketed as HCQ sulfate in film-coated or coated tablets for oral use. No pediatric liquid form is currently available on the market. The purpose of the present study is to develop oral liquid formulations for HCQ at 50 mg/mL with two different oral vehicle suspensions, namely ORA-Plus®/ORA-Sweet® (ORA) and Syrspend® SF PH 4 (SYR). Methods The suspension stability was assessed in different storage conditions (4 and 25 °C). A high-pressure liquid chromatography (HPLC) stability-indicating method with UV detection was developed to determine HCQ concentrations in the different formulations, and detect potential degradation products. Physical parameters, e.g. pH and osmolality were also monitored during the period of the stability study. Results HCQ concentration, osmolality, and pH remained stable for 90 days at 4 and 30 °C for HCQ in 50% ORA-Plus®/50% ORA-Sweet®. For HCQ suspension in SYR, the suspension remained stable 90 days at 4 °C and 60 days at 30 °C. Conclusions For all preparations, no significant physical or chemical modification was noticed during the period of the study.