New Regimen Makes Treating Latent Tuberculosis Infection Easier

RADM Kenneth G. Castro, MD


May 22, 2012

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Hello. I am Dr. Kenneth Castro, Director of the Division of Tuberculosis Elimination at the Centers for Disease Control and Prevention. I am happy to speak with you as part of the CDC Expert Video Commentary Series on Medscape. Today I will talk about the recently released CDC guidelines[1] for the use of a new treatment regimen for latent tuberculosis (TB) infection.

Preventing TB disease by treating those with latent TB infection is a cornerstone of the US strategy for TB elimination. This new regimen, referred to as the "12-dose regimen," is the biggest breakthrough in treatment for latent TB infection since the 1960s. This regimen reduces treatment from 270 doses given daily for 9 months to 12 once-weekly doses given for 3 months using a combination of isoniazid and rifapentine. Directly observed therapy is recommended for this regimen, and patients should undergo monthly clinical monitoring, including inquiries about side effects and a physical assessment for signs of adverse effects.

A recent large randomized controlled trial found the 12-dose regimen to be as effective for preventing TB as other treatment regimens and more likely to be completed than the current US standard regimen of 9 months of isoniazid given daily, without directly observed therapy.[2]

The 12-dose regimen doesn't replace other recommended options for treating latent TB infection. It is recommended as an equal alternative for otherwise healthy persons, 12 years of age and older, who have latent TB infection and factors that are predictive of progressing to TB disease. Such factors include recent exposure to a person with infectious TB disease, or persons who have a positive tuberculin skin test or a positive blood test for TB infection. The 12-dose regimen is also an option for HIV-infected persons who are otherwise healthy and not taking antiretroviral medicines. The regimen can be considered for other patients when it offers practical advantages, such as completion within a limited timeframe.

This new regimen is not recommended for children younger than 2 years of age. The preferred regimen for children aged 2-11 years old is 9 months of daily isoniazid. The new 12-dose regimen is also not recommended for HIV-infected persons taking antiretroviral medicines, pregnant women, women who expect to become pregnant during treatment, and persons who have latent TB infection with strains presumed to be resistant to isoniazid or rifapentine. These persons should be treated with other available regimens.

The choice between the 12-dose regimen and other approved latent TB infection treatment regimens depends on several factors, including the feasibility of providing directly observed therapy, drug availability, patient monitoring, expectation of treatment completion, and the preferences of the patient and the prescribing physician.

For more information about latent TB infection, visit the CDC Website.

Web Resources

CDC Tuberculosis

CDC. Treatment Options for Latent Tuberculosis Infection

CDC. Recommendations for use of an isoniazid-rifapentine regimen with direct observation to treat latent Mycobacterium tuberculosis infection.

RADM Kenneth G. Castro, MD, has served, since January 1993, as director, Division of Tuberculosis Elimination, National Center for HIV, Viral Hepatitis, STD, and TB Prevention (NCHHSTP), US Centers for Disease Control and Prevention (CDC). In this role, Dr. Castro leads the team of technical experts devoted to tuberculosis (TB) elimination efforts in the United States: his division sponsors TB prevention, control, and research activities throughout the nation and other parts of the world. Since 1995, he has served as co-Chair of the US Federal Tuberculosis Task Force. Recognizing the importance and magnitude of global tuberculosis, Dr. Castro has advanced the involvement by the United States in global tuberculosis control efforts, serving as an expert advisor to the World Health Organization (WHO) and the International Union Against Tuberculosis and Lung Diseases. He is a founding member of the global Stop TB Partnership and member of its Coordinating and Executive Boards. He has been called upon on several occasions to provide Congressional Testimony to describe the serious public health problems posed by TB, HIV-associated TB, and multidrug resistant (MDR) TB -- both domestically and globally. Since the 2006 description of extensively drug resistant (XDR) TB, he has provided national and global leadership in the development of a coordinated response to this urgent health problem. In recent years he has also served other key leadership roles during temporary assignments, as Acting Chief Health Officer for CDC's Emergency Operations response to the 2009 pandemic Influenza A (H1N1) in May 2009, and as Acting Incident Commander of CDC's Emergency Operations response to the 2010 Haiti Earthquake in late January 2010 -- while the Incident Commander traveled to Haiti.

In an unusual distinction afforded to a division director, Castro, a Commissioned Corps Officer in the US Public Health Service, was promoted to the flag rank of Assistant Surgeon General (RADM, O-7), in May 2000. In September 2008, RADM Castro was designated Commanding Flag Officer, CDC/ATSDR Commissioned Corps. In this capacity he acts as the Flag representative with oversight for > 900 Commissioned Officers at CDC/ATSDR.

Prior to serving as director of CDC's Division of TB Elimination, Castro worked as the assistant director for TB and HIV, Office of HIV/AIDS at CDC from May to December 1992. He was appointed to the office of the Associate Director of HIV/AIDS to coordinate CDC-wide HIV-associated TB activities in May 1992, after serving for almost two years as the assistant chief of the epidemiology branch in the Division of HIV/AIDS in the National Center for Infectious Diseases. From July 1989 until August 1990, he served as special assistant to the director for science in the Division of HIV/AIDS. Castro began his career with CDC in 1983 as an Epidemic Intelligence Service (EIS) officer with the AIDS Program, where he became a staff medical epidemiologist after completing the EIS training in 1985.

A physician-scientist trained in epidemiology, Dr. Castro has a specialty in internal medicine and subspecialty in infectious diseases. He received his bachelor's degree in 1974 from the University of Puerto Rico; completed post-graduate biology studies at Northeastern University in Boston in 1976, and his medical doctorate from the State University of New York at Stony Brook School of Medicine in 1980. He completed his internal medicine postgraduate training in 1983 at the residency program in social medicine at the Montefiore Medical Center, Albert Einstein College of Medicine in New York. From 1988 until 1989, he completed a fellowship in infectious diseases at the Emory University School of Medicine, where his work focused on describing the increase in the number of people with TB and its association with the HIV/AIDS epidemic. In 2008-2009, he completed the National Preparedness Leadership Institute Program at the Harvard School of Public Health and Harvard Kennedy School of Government. Dr. Castro also holds an academic appointment as adjunct clinical faculty member of the Division of Infectious Diseases, Department of Medicine, Emory School of Medicine, and has hospital privileges at the infectious diseases clinic at Grady Health System in Atlanta.

An award-winning author of more than 125 scholarly publications, Dr. Castro serves as a peer reviewer for numerous scientific journals and is an associate editor for the journals International Journal of Tuberculosis and Lung Disease and Emerging infectious Diseases. He also maintains memberships in the leading scientific societies in his field. A native Puerto Rican, Castro speaks fluent Spanish, and has frequently served as advisor to the Puerto Rico Department of Health, the Pan American Health Organization, World Health Organization, and several Ministries of Health in countries where TB and HIV constitute major public health problems. In 2008 Dr. Castro was recognized by the Hispanic Officers Advisory Committee, US Public Health Service Commissioned Corps with the prestigious Juan Carlos Finlay award.


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