New Delhi: According to various reports, almost 25% of the world’s population is latently (inactively) infected with tuberculosis (TB) and almost 3,816 people die every day. The epidemiological data from World Health Organization (WHO) suggests that India accounts for almost 26% of total world TB cases, which is almost ~ 2,640,000 cases in 2020.
Currently, doctors are using combination therapy to combat the TB infection and this includes four drugs (daily for months): rifampicin (RIF), isoniazid (INH), pyrazinamide (PYZ), and ethambutol (EMB). Although these methods are efficient to control TB to a great extent, but irregular medicine, ignorance of caregivers and patients, and inefficient drug delivery/management systems can give a rise to drug-resistant bacteria that are difficult to treat. Surprisingly India has the highest burden (total 465,000 cases) of TB patients with multidrug-resistant (MDR) TB and it is alarming to find out a different strategy.
In a recently published study in “Nanoscale” journal (of Royal Society of Chemistry), the researchers from the Regional Centre for Biotechnology (RCB) and the National Institute of Immunology (NII) (under the guidance of Dr. Avinash Bajaj from RCB and Dr. Vinay Nandicoori from NII) discovered a new approach to address this issue.
What is TB-Gel and how can it be useful?
TB-Gel is a novel drug delivery method, with which these drug combinations can be released in a controlled manner for a long period. According to one of the first authors, Dr. Vijay Soni (currently working at Weill Cornell Medicine New York), “We have developed a hydrogel-based delivery system (derived from a low molecular weight bile acid peptide) where we have entrapped four first-line anti-TB drugs (namely Isoniazid, Rifampicin, Pyrazinamide, and Ethambutol) in it, and we called it TB-Gel. The TB-Gel maintained its integrity, elasticity, and strength, and can easily pass through the syringe. It is non-immunogenic (harmless) and implantable under the skin and can release these four drugs (in the therapeutic range) for a prolonged period (up to 15 days in mice).
Is it biocompatible?
Researchers have done extensive studies in mice and checked the drug release rate with changing porosity of the hydrogel. They have also infected mice with tuberculosis and checked the efficacy of TB-Gel as compared to the oral drug delivery system.
Dr. Sanjay Pal (another first author, currently working at National Cancer Institute, USA) mentioned that in their “TB infection mice model”, TB-Gel treated mice showed significantly lower infection as compared to the group of mice that were administered with daily oral doses. “As TB-Gel can maintain the optimum drug levels in the blood, without taking daily oral medications, therefore we found that it reduces the systematic toxicity and side effects of these drugs. Hence this system can lessen the requirement of regular dosing, it can be very helpful for TB treatment management and decreases the likelihood of drug resistance emergence.”
Novel TB-Gel can release four front line anti-TB drugs and outperforms the oral doses of this combination. Thus reducing the TB infection in mice efficiently. (Image Credit: Nanoscale and Authors)
Why TB-Gel is needed?