CSIR-National Chemcial Laboratory (NCL) has developed an anti-tuberculosis cocrystal drug, pitched to be a promising one through its stable formulation of 4-FDC (4 drugs fixed dosage). Tuberculosis is still rampant among Indians and is one of the main killer diseases globally.
As per the recommendation by the World health Organisation (WHO), Rifampicin (RIF), Isoniazid (INH), Pyrazinamide (PZA), and Ethambutol dihydrochloride (EDH) drugs are used for the treatment of TB. The use of fixed dose combination (2-drug, 3-drug and 4-drug FDCs) for the treatment of tuberculosis was first recommended in 1994 by the WHO and International Union against Tuberculosis and Lung Disease (IUATLD).
In 1999, the 4-drug FDC tablet was included in the WHO Model List of Essential Drugs inclusive of these four drugs. The 4-FDC tablets, however, had quality and stability issues, including poor bio-availability of Rifampicin and instability during its storage, which raised concerns on the utility of this FDC. It was essential to address the quality and stability issues.
The team of NCL researchers, led by Prof A K Nangia, studied the reasons for instability caused to 4-FDC chemical structures. The researchers developed pharmaceutically stable cocrystals so that the drug would not form any by-products even while it would inhibit cross-section between Isoniazid and Rifampicin. The team demonstrated a five-fold increased stability levels in the newly devised cocyrstal combination meant for TB.
Sharing the biggest advantage, Nangia said, “Stable cocrystal drug with longer shelf life will improve the prospects of transport logistics and inventory management of TB drugs.”