Colloidal carriers: a rising tool for therapy of tuberculosis

Tuberculosis (TB) is the second most deadly infectious disease, caused mainly by M. tuberculosis in humans, usually affecting the lungs; it also attacks other parts of the body. The design of novel antibiotics attempts to overcome drug resistance, to shorten the treatment course, and to reduce drug interactions with antiretroviral therapies. Overcoming technological drawbacks of these therapeutic agents as well as improving the effectiveness of the drugs by targeting the infection reservoirs remain the central aims of pharmaceutical technology. In this framework, colloidal carriers appear as one of the most promising approaches for the development of more effective and compliant medicines by releasing the drugs slowly over prolonged time periods and reducing the current costs of treatment. Due to unique physicochemical properties (ultrasmall and controllable size, large surface area to mass ratio, high reactivity, and functionalizable structure) of colloidal carriers, they can facilitate the administration of antitubercular drugs, thereby overcoming some of the limitations in traditional antitubercular therapeutics. In recent years, encapsulation of antitubercular drugs in colloidal carrier systems is emerging as an innovative and promising alternative with enhanced therapeutic effectiveness and reduced undesirable side effects of the encapsulated drugs. The present review aims to describe the current conventional as well as combination drug therapy with special consideration towards the emerging role of novel colloidal carriers designed and targeted against TB. Colloidal carriers employing drugs alone or in combination targeted towards the site of action could lead to reduction in duration of conventional treatment, higher patient fulfillment, and prevention of antitubercular drug resistance or toxicity.