Tuberculosis Preventive Treatment Update - U.S. President's Emergency Plan for AIDS Relief, 36 Countries, 2016-2023.

Tuberculosis (TB) is the leading cause of death among persons with HIV. In 2022, an estimated 167,000 TB-related deaths occurred globally among persons with HIV. TB preventive treatment (TPT) helps prevent TB disease and is recommended for persons at high risk for developing TB, including those with HIV. TPT, when taken with antiretroviral treatment (ART), can reduce TB-attributable deaths among persons with HIV. In 2018, the U.S. President's Emergency Plan for AIDS Relief (PEPFAR) program committed to offer one course of TPT to all eligible clients receiving ART. This analysis describes trends in TPT initiation and completion among PEPFAR-supported programs in 36 countries in Africa, Central and South America, and Asia during fiscal years (FYs) 2017-2023. Overall, TPT initiation rates peaked in FY19, a possible sign of programmatic saturation. TPT initiation among clients who had been on ART <6 months reached 59%, and overall completion rates up to 87% were reported. Approximately 13 million persons with HIV have completed TPT since FY17, but widespread adoption of shorter regimens, patient-centered approaches, and electronic medical record systems might be needed to ensure full TPT coverage. Through PEPFAR's partnership with national HIV programs, TPT has become the standard of care for persons with HIV.

Tuberculosis preventive treatment uptake among adults living with human immunodeficiency virus: Analysis of Zimbabwe population-based human immunodeficiency virus impact assessment 2020.

BACKGROUND: Tuberculosis remains the leading cause of death by an infectious disease among people living with HIV (PLHIV). TB Preventive Treatment (TPT) is a cost-effective intervention known to reduce morbidity and mortality. We used data from ZIMPHIA 2020 to assess TPT uptake and factors associated with its use. METHODOLOGY: ZIMPHIA a cross-sectional household survey, estimated HIV treatment outcomes among PLHIV aged ≥15 years. Randomly selected participants provided demographic and clinical information. We applied multivariable logistic regression models using survey weights. Variances were estimated via the Jackknife series to determine factors associated with TPT uptake. RESULTS: The sample of 2419 PLHIV ≥15 years had 65% females, 44% had no primary education, and 29% lived in urban centers. Overall, 38% had ever taken TPT, including 15% currently taking TPT. Controlling for other variables, those screened for TB at last HIV-related visit, those who visited a TB clinic in the previous 12 months, and those who had HIV viral load suppression were more likely to take TPT. CONCLUSION: The findings show suboptimal TPT coverage among PLHIV. There is a need for targeted interventions and policies to address the barriers to TPT uptake, to reduce TB morbidity and mortality among PLHIV.

Rolling Out Xpert® MTB/RIF for TB Detection in HIV-Infected Populations:An Opportunity for Systems Strengthening.

BACKGROUND: To eliminate preventable deaths, disease and suffering due to tuberculosis (TB), improved diagnostic capacity is critical. The Cepheid Xpert® MTB/RIF assay is recommended by the World Health Organization as the initial diagnostic test for people with suspected HIV-associated TB. However, despite high expectations, its scale-up in real-world settings has faced challenges, often due to the systems that support it. OPPORTUNITIES FOR SYSTEM STRENGTHENING: In this commentary we discuss needs and opportunities for systems strengthening to support widespread scale-up of Xpert® MTB/RIF as they relate to each step within the TB diagnostic cascade, from finding presumptive patients, to collecting, transporting and testing sputum specimens, to reporting and receiving results, to initiating and monitoring treatment and, ultimately, to ensuring successful and timely treatment and cure. Investments in evidence-based interventions at each step along the cascade and within the system as a whole will augment not only the utility of Xpert® MTB/RIF, but also the successful implementation of future diagnostic tests. CONCLUSION: Xpert® MTB/RIF will only improve patient outcomes if optimally implemented within the context of strong TB programs and systems. Roll-out of this technology to people living with HIV and others in resource-limited settings offers the opportunity to leverage current TB and HIV laboratory, diagnostic and programmatic investments, while also addressing challenges and strengthening coordination between laboratory systems, laboratory-program interfaces, and TB-HIV program interfaces. If successful, the benefits of this tool could extend beyond progress towards global End TB Strategy goals, to improve system-wide capacity for global disease detection and control.

Provision of antiretroviral therapy for HIV-positive TB patients--19 countries, sub-Saharan Africa, 2009-2013.

Considerable progress has been made in the provision of life-saving antiretroviral therapy (ART) for persons with human immunodeficiency virus (HIV) infection worldwide, resulting in an overall decrease in HIV incidence and acquired immunodeficiency syndrome (AIDS)-related mortality. In the strategic scale-up of HIV care and treatment programs, persons with HIV and tuberculosis (TB) are a priority population for receiving ART. TB is the leading cause of death among persons living with HIV in sub-Saharan Africa and remains a potential risk to the estimated 35 million persons living with HIV globally. Of the 9 million new cases of TB disease globally in 2013, an estimated 1.1 million (13%) were among persons living with HIV; of the 1.5 million deaths attributed to TB in 2013, a total of 360,000 (24%) were among persons living with HIV. ART reduces the incidence of HIV-associated TB disease, and early initiation of ART after the start of TB treatment reduces progression of HIV infection and death among HIV-positive TB patients. To assess the progress in scaling up ART provision among HIV-positive TB patients in 19 countries in sub-Saharan Africa with high TB and HIV burdens, TB and HIV data collected by the World Health Organization (WHO) were reviewed. The results found that the percentage of HIV-positive TB patients receiving ART increased from 37% in 2010 to 69% in 2013. However, many TB cases among persons who are HIV-positive go unreported, and only 38% of the estimated number of HIV-positive new TB patients received ART in 2013. Although progress has been made, the combination of TB and HIV continues to pose a threat to global health, particularly in sub-Saharan Africa.

GeneXpert for TB diagnosis: planned and purposeful implementation.

Xpert MTB/RIF is a major advance for TB diagnostics, especially for multidrug-resistant (MDR) TB and HIV-associated TB. But implementation concerns including cost, technical support requirements, and challenging demands of providing second-line TB drugs for diagnosed MDR-TB cases call for gradual, careful introduction based on country circumstances.

PEPFAR support for the scaling up of collaborative TB/HIV activities.

The US President's Emergency Plan for AIDS Relief (PEPFAR) has supported a comprehensive package of care in which interventions to address HIV-related tuberculosis (TB) have received increased funding and support in recent years. PEPFAR's TB/HIV programming is based on the World Health Organization's 12-point policy for collaborative TB/HIV activities, which are integrated into PEPFAR annual guidance. PEPFAR implementing partners have provided crucial support to TB/HIV collaboration, and as a result, PEPFAR-supported countries in sub-Saharan Africa have made significant gains in HIV testing and counseling of TB patients and linkages to HIV care and treatment, intensified TB case finding, and TB infection control. PEPFAR's support of TB/HIV integration has also included significant investment in health systems, including improved laboratory services and educating and enlarging the workforce. The scale-up of antiretroviral therapy along with support of programs to increase HIV counseling and testing and improve linkage and retention in HIV care may have considerable impact on TB morbidity and mortality, if used synergistically with isoniazid preventive therapy, intensified case finding, and infection control. Issues to be addressed by future programming include accelerating implementation of isoniazid preventive therapy, increasing access and ensuring appropriate use of new TB diagnostics, supporting early initiation of antiretroviral therapy for HIV-infected TB patients, and strengthening systems to monitor and evaluate program implementation.

Opportunities and challenges for cost-efficient implementation of new point-of-care diagnostics for HIV and tuberculosis.

Stakeholders agree that supporting high-quality diagnostics is essential if we are to continue to make strides in the fight against human immunodeficiency virus (HIV) and tuberculosis. Despite the need to strengthen existing laboratory infrastructure, which includes expanding and developing new laboratories, there are clear diagnostic needs where conventional laboratory support is insufficient. Regarding HIV, rapid point-of-care (POC) testing for initial HIV diagnosis has been successful, but several needs remain. For tuberculosis, several new diagnostic tests have recently been endorsed by the World Health Organization, but a POC test remains elusive. Human immunodeficiency virus and tuberculosis are coendemic in many high prevalence locations, making parallel diagnosis of these conditions an important consideration. Despite its clear advantages, POC testing has important limitations, and laboratory-based testing will continue to be an important component of future diagnostic networks. Ideally, a strategic deployment plan should be used to define where and how POC technologies can be most efficiently and cost effectively integrated into diagnostic algorithms and existing test networks prior to widespread scale-up. In this fashion, the global community can best harness the tremendous capacity of novel diagnostics in fighting these 2 scourges.

Bicistronic lentiviruses containing a viral 2A cleavage sequence reliably co-express two proteins and restore vision to an animal model of LCA1.

The disease processes underlying inherited retinal disease are complex and are not completely understood. Many of the corrective gene therapies designed to treat diseases linked to mutations in genes specifically expressed in photoreceptor cells restore function to these cells but fail to stop progression of the disease. There is growing consensus that effective treatments for these diseases will require delivery of multiple therapeutic proteins that will be selected to treat specific aspects of the disease process. The purpose of this study was to design a lentiviral transgene that reliably expresses all of the proteins it encodes and does so in a consistent manner among infected cells. We show, using both in vitro and in vivo analyses, that bicistronic lentiviral transgenes encoding two fluorescent proteins fused to a viral 2A-like cleavage peptide meet these expression criteria. To determine if this transgene design is suitable for therapeutic applications, we replaced one of the fluorescent protein genes with the gene encoding guanylate cyclase-1 (GC1) and delivered lentivirus carrying this transgene to the retinas of the GUCY1*B avian model of Leber congenital amaurosis-1 (LCA1). GUCY1*B chickens carry a null mutation in the GC1 gene that disrupts photoreceptor function and causes blindness at hatching, a phenotype that closely matches that observed in humans with LCA1. We found that treatment of these animals with the 2A lentivector encoding GC1 restored vision to these animals as evidenced by the presence of optokinetic reflexes. We conclude that 2A-like peptides, with proper optimization, can be successfully incorporated into therapeutic vectors designed to deliver multiple proteins to neural retinal. These results highlight the potential of this vector design to serve as a platform for the development of combination therapies designed to enhance or prolong the benefits of corrective gene therapies.

Use of generic antiretroviral agents and cost savings in PEPFAR treatment programs.

CONTEXT: One of the biggest hurdles to the rapid scale-up of antiretroviral therapy in the developing world was the price of antiretroviral drugs (ARVs). Modification of an existing US Food and Drug Administration (FDA) process to expedite review and approval of generic ARVs quickly resulted in a large number of FDA-tentatively approved ARVs available for use by the US President's Emergency Plan for AIDS Relief (PEPFAR). OBJECTIVE: To evaluate the uptake of generic ARVs among PEPFAR-supported programs in Guyana, Haiti, Vietnam, and 13 countries in Africa, and changes over time in ARV use and costs. DESIGN, SETTING, AND PARTICIPANTS: An annual survey from 2005 to 2008 of ARVs purchased in 16 countries by PEPFAR implementing and procurement partners (organizations using PEPFAR funding to purchase ARVs). MAIN OUTCOME MEASURES: Drug expenditures, ARV types and volumes (assessed per pack, a 1-month supply), proportion of generic procurement across years and countries, and cost savings from generic procurement. RESULTS: ARV expenditures increased from $116.8 million (2005) to $202.2 million (2008); and procurement increased from 6.2 million to 22.1 million monthly packs. The proportion spent on generic ARVs increased from 9.17% (95% confidence interval [CI], 9.17%-9.18%) in 2005 to 76.41% (95% CI, 76.41%-76.42%) in 2008 (P < .001), and the proportion of generic packs procured increased from 14.8% (95% CI, 14.79%-14.84%) in 2005 to 89.33% (95% CI, 89.32%-89.34%) in 2008 (P < .001). In 2008, there were 8 PEPFAR programs that procured at least 90.0% of ARV packs in generic form; South Africa had the lowest generic procurement (24.7%; 95% CI, 24.6%-24.8%). Procurement of generic fixed-dose combinations increased from 33.3% (95% CI, 33.24%-33.43%) in 2005 to 42.73% (95% CI, 42.71%-42.75%) in 2008. Estimated yearly savings generated through generic ARV use were $8,108,444 in 2005, $24,940,014 in 2006, $75,645,816 in 2007, and $214,648,982 in 2008, a total estimated savings of $323,343,256. CONCLUSION: Among PEPFAR-supported programs in 16 countries, availability of generic ARVs was associated with increased ARV procurement and substantial estimated cost savings.

Expression characteristics of dual-promoter lentiviral vectors targeting retinal photoreceptors and Müller cells.

PURPOSE: Growing evidence suggests that successful treatment of many inherited photoreceptor diseases will require multi-protein therapies that not only correct the genetic defects linked to these diseases but also slow or halt the related degenerative phenotypes. To be effective, it is likely that therapeutic protein expression will need to be targeted to specific cell types. The purpose of this study was to develop dual-promoter lentiviral vectors that target expression of two proteins to retinal cones and rods, rods only, or Müller cells. METHODS: Dual-promoter lentivectors were constructed using the following promoters: Xenopus opsin promoter (XOPS)1.3, murine opsin promoter (MOPS), interphotoreceptor retinoid binding protein promoter (IRBP156), rhodopsin kinase (RK), neural retina leucine zipper (NRLL), vimentin (VIM), cluster differentiation (CD44), and glial fibrillary acidic protein (GFAP). Vectors were packaged and injected into the neural tubes of chicken embryos. The activities of the promoters alone, in duplicate, or when paired with a different promoter were analyzed in transduced, fully-developed retinas, using direct fluorescent and immunofluorescent microscopy. RESULTS: IRBP156, NRLL, and RK were active in cones and rods while XOPS1.3 was active only in rods. Of the glial promoters, only GFAP activity was restricted to Müller cells; both VIM and CD44 were active in Müller and neural cells. Dual-promoter vectors carrying IRBP156 and RK or XOPS1.3 and MOPS, in the order listed, exhibited robust expression of both reporter transgenes in cones and rods or rods only, respectively. Expression of the upstream transgene was much lower than the downstream transgene in dual-promoter vectors constructed using two copies of either RK or IRBP156. Analyses of the expression of a dual-promoter vector carrying CD44 and VIM in the order listed showed that the activity of the VIM promoter was more restricted to glial cells when paired with the CD44 promoter, while the activity of the CD44 promoter was inhibited to the extent that no CD44-driven reporter protein was detected in transduced cells. CONCLUSIONS: We have identified two dual-promoter vectors, one that targets cones and rods and one that targets rods alone. Both vectors reliably express the two proteins encoded by the transgenes they carry. When two well matched promoters are not available, we found that it is possible to target expression of two proteins to single cells using dual-promoter vectors carrying two copies of the same promoter. These vectors should be useful in studies of retina when co-delivery of a reporter protein with an experimental protein is desired or when expression of two exogenous proteins in targeted cells is required.

Role of the US President's Emergency Plan for AIDS Relief in responding to tuberculosis and HIV coinfection.

The intersection of tuberculosis (TB) and human immunodeficiency virus (HIV) infection has eroded gains made in TB control, because previously well-functioning national TB programs have been overwhelmed by the dual challenges posed by TB and HIV coinfection. The US President's Emergency Plan for AIDS Relief (PEPFAR), through its direct support of >2.4 million persons receiving HIV treatment and, in 2009, support of >308,000 HIV-infected persons receiving TB treatment, works closely with national governments and other partners to strengthen the response to TB and HIV coinfection. PEPFAR-supported activities fall within the World Health Organization's 2004 framework for collaborative TB and HIV activities, including critical interventions to (1) develop organizational methods of collaboration across the 2 programs, (2) reduce the burden of HIV infection among patients with TB, and (3) reduce the burden of TB among persons with HIV infection or AIDS. To date, PEPFAR and partners have made important gains in coverage and scope of HIV testing, referral, and antiretroviral therapy for patients with TB. TB screening of HIV-infected patients is also beginning to increase, although greater progress needs to be made in increasing access to isoniazid preventive therapy and strengthening TB infection control. Continued strategic integration of TB and HIV interventions into PEPFAR-supported programs is essential to easing the patient burden of dual infection, improving patient outcomes, and, ultimately, decreasing rates of TB in areas with a high prevalence of TB.