A team of researchers led by Prof Ashwini Nangia, from University of Hyderabad has improved the shelf life of an important brain cancer drug called temozolomide, using pharmaceutical co-crystal technique.

When exposed for longer period, temozolomide gets discoloured and loses its medicinal efficacy. Thanks to the research team, the drug which had a shelf life of just eight weeks is now being extended to 24 weeks. This new development would benefit brain cancer patients living in tropical regions including India.

“The pharmaceutical co-crystal method is relatively  a new technique and  it has been evolved just 10 years ago. Not many scientists have experimented with this technique earlier. This technique was just confined to model compounds. We have taken a lead and have succeeded in extending the shelf life of ‘temozolomide’ an important drug used for treating patients suffering from brain cancer,” explained Prof. Ashwini Nangia.

Temozolomide is the only approved drug in the last two decades for use in chemotherapy to treat aggressive brain tumour called glioblastoma multiforme. This drug, however, is unstable with poor shelf life. It loses colour and medicinal efficacy within eight weeks.

Adding further, the professor said, “Temozolomide reacts in tropical climate and this causes the drug to lose colour. It also loses its medicinal activity. For patients, it is disturbing to see a dark tablet. The formulation of the drug has some issues relating to stability. Our method improves the efficacy and aesthetic appeal of the drug.”

A part from Prof. Ashwini Nangia the other members of the research team include Jagadish Babu and Palash Sanphui. The research thoroughly mixed solids comprising temozolomide with an acid, forming pharmaceutical co-crystals. The acid effectively protects the drug from degradation, and the co-crystals showed no signs of discolouration for over six months, even in humid air. A part from increasing the shelf life the research team has also ensured that the drug keeps its medicinal properties intact for effective treatment of brain cancer. Temozolomide is stable in the presence of acid, but when white tablets of the drug are stored for an extended period, they turn light pink or tan. This discolouration is indicative of degradation by water in neutral or basic conditions, which lowers the effectiveness of the drug, and has the potential to disconcert patients. Temozolomide is also prescribed for treatment of skin cancer melanoma.

Preliminary assessment of the pharmacological properties of the co-crystals suggests that they could be suitable for use in formulation development, Prof. Nangia said. “In drug development, the efficacy of the active drug ingredient is important, but proper formulation is also essential to ensure that the administered drug acts as it should. Our research also revealed that acids could protect powders of the drug from discolouration and loss of activity,” he explained.

Government is the main source of funding for this research. The three funding bodies are Department of Science and Technology (DST), Council for Scientific and Industrial Research (CSIR) and university grants commission. The clinical trial part of the research is being funded by Department of Biotechnology.