Development of efavirenz cocrystals from stoichiometric solutions by spray drying technology

Efavirenz (EFA) is an oral human immunodeficiency virus type-1 drug with extremely poor aqueous solubility. The present study investigates the potential of spray drying as a technique for generation of EFA cocrystals. Efavirenz-Glutaric acid cocrystal (EGC) was selected as model cocrystal system for this study. The EGC cocrystals were further characterized by DSC, XRD, FTIR, HSM and dissolution studies. The thermal evaluation of cocrystals indicates complete different melting endotherm, the HSM studies were in good agreement with DSC study. The unique 2θ values apart from EFA and glutaric acid indicates EGC cocrystal formation. FTIR studies also confirmed formation of hydrogen bonding between EFA and glutaric acid. The cocrystals showed improved solubility and dissolution rate leading to faster absorption and a may have better bioavailability of the active drug.