Nontuberculous mycobacteria (NTM) are Mycobacteriaceae species that can cause the onset of illness in humans. NTM are present naturally in the soil and air but are not the causative agents of tuberculosis. These bacteria have been classified as nontuberculosis to differentiate them from the tuberculosis-causing bacteria, also known as the Mycobacterium tuberculosis complex.
Despite the fact that NTM are everywhere in the environment, in many countries, the conditions they cause are not reportable. The key reason is that person-to-person transmission of the disease cannot be substantiated. Because of this lack of substantiation, the condition is officially not a concern to public health. Generally because the condition has not raised many “red flags,” investigators have also not made much movement towards comprehending the significance of the condition, in determining preventive measures, or in optimizing treatment protocols.
Moreover, it is often difficult to pinpoint the location and timing of personal exposure. It is difficult to understand why certain members of the population develop NTM infections, while others do not. Not many clinical trials on the subject have been undertaken and those that have, for the most part, have been small and non-randomized. These trials do indicate that the rates of recurring NTM pulmonary disease are high. Researchers are not sure if treatment failures or re-infection is causing certain people to develop the disease again.
A growing number of NTM conditions should spur the development of reliable diagnostics and novel medicines, which would address the disease. Current small clinical trials must give way to larger-scale randomized trials. Such studies would facilitate optimum drug discovery - creating those medicines which would bring about the best health outcomes with the least toxicity - and the development of the best treatment protocols.
These organisms may cause less harm if how they evolve and are transmitted is better understood. Even research related to Mycobacterium tuberculosis might be applicable to NTM research and yield benefits for treating NTM. It might be possible to design a blood assay similar to a tuberculosis diagnostic.
One company, Insmed, Bridgewater, NJ, USA, is developing and investigating treatments for rare lung diseases. It is conducting a randomized, phase III, open-label study, to determine the effectiveness of liposomal amikacin for inhalation as part of a several-drug treatment plan for patients with NTM disease caused by the mycobacterium avium complex (MAC). In addition to determining how helpful the therapy would be for current treatment plans, the research would shed light on any side effects amikacin might cause.
A Strategic Plan
One organization, NTM Info and Research Inc., Coral Gables, FL, USA, is focused specifically on improving the lives of those infected with NTM, partly through research and education efforts. As part of its strategic plan, the company sponsors Rapid Information Pilot Studies (RIPS), which provide information on important research in order to obtain funding for large-scale research. In addition, it supports multi-centered efforts aimed at helping those suffering from NTM, as well as helping clinicians and NTM scientists. The organization also works with various patient support groups. NTM Info and Research funds or co-funds analyze patient vulnerabilities, and study the sources of and treatments for NTM. It examines the prevalence of the disease in the USA.
The RIPS program funds short-term scientific investigations with the aim of generating longer-term research. Individual studies may receive funding of up to $50,000 each, and are completed in a year or less. The research results form the basis for funding large scale, multi-centered studies. Research completed to date includes Pulmonary NTM in Showers and the Genome Sequence of Mycobacterium abscessus.
Currently-recruiting clinical trials involve identifying priorities and roadmaping research into bronchiectasis. Additionally, a survey is being conducted on the use of proton pump inhibitors for treating gastroesophageal reflux disease and related conditions. Information gained in this survey may determine future NTM treatments.
Reviewed by Afsaneh Khetrapal BSc (Hons)