When your eye gets infected with conjunctivitis or the common Madras Eye, your doctor could prescribe a broad spectrum antibiotic called Sulfacetamide (SACT). Often, we end up applying more of the drug than perhaps necessary for treatment because of the loss of a significant portion of the active drug ingredient. The simple reason is that while administering, your eyes blink and the tears that roll out wash away much of this active ingredient.
A technique to overcome this problem and make the drug more effective has been developed by Ashwini Nangia and his doctoral student Rajesh Goud from the School of Chemistry at the University of Hyderabad (UoH). What is their solution based on? Don’t be surprised, its the familiar caffeine found in our daily morning cuppa.
They co-crystallised caffeine with SACT. This increased the availability of the drug at the site of the eye problem and rendered it more efficient. “We tried a few additives before zeroing on caffeine as the best. It reduced the solubility and increased the effective time the drug remains in the eye. This will help in lowering the drug use by 30-40 per cent, which in turn means cutting costs for patients”, he told
The duo published their findings in the peer reviewed Journal of Crystal Engineering Communication and Chemistry World.
The field of co-crystal drugs is quite nascent, with hardly any commercial product available in the market. “We have to try our candidate drug in animal and human trials, which we shall follow up soon”, he said.
What they do is help in modifying existing drugs to help in improving bio-availability, solubility or dissolution properties (which drastically improve the potency of drugs) without disturbing the basic molecule (Active Pharmaceutical Ingredient).
Earlier this year, Nangia and researchers in collaboration with the National Institute of Nutrition also reported improving the stability and shelf life of the anti-cancer drug, Temozolomide, used in treatment of brain tumour by developing a stable co-crystal.
He has established a R&D Venture, Crystalin Research at the University’s Technology Business Incubator funded by the Department of Science and Technology. Srinivasulu Aitipamula , a pharmaceutical co-crystal expert at the Institute of Chemical and Engineering Sciences, Singapore, says the identification of intermolecular interactions that can be altered by co-crystal formation is what makes this research stand out.