Operational research as a mechanism to improve treatment outcomes for drug-resistant TB in the WHO European Region.

In 2022, the WHO European Region accounted for 15.1% of all incident rifampicin-resistant/multidrug-resistant TB (RR/MDR-TB) cases. Most occurred in 18 high-priority countries of eastern Europe and central Asia, many of which joined an initiative led by the WHO Regional Office for Europe. The aim was to introduce three, fully oral, 9-month modified shorter treatment regimens (mSTR) to treat RR/MDR-TB under operational research conditions. The three regimens were: 1) bedaquiline + linezolid + levofloxacin + clofazimine + cycloserine (BdqLzdLfxCfzCs); 2) BdqLzdLfxCfz + delamanid (Dlm) for children over 6 years of age and adults; and 3) DlmLzdLfxCfz for children under 6 years of age. The project aimed to enhance treatment success, facilitate mSTR implementation, promote quality of care and build research capacity, while also contributing to global knowledge on all-oral mSTR use. Between April 2020 and June 2022, >2,800 patients underwent mSTR treatment in the WHO European Region. This unique experience promoted further collaboration with national tuberculosis programmes, health authorities, experts and donors within and outside Europe, with a focus on implementing operational research and improving the quality of care in high TB burden countries of the region. In the hope of encouraging others to adopt this model, we have described the principles of the initiative, its strengths and weaknesses and next steps.

En 2022, la Région européenne de l'OMS a recensé 15,1% de l'ensemble des cas de TB résistante à la rifampicine/multirésistante aux médicaments (RR/MDR-TB). La majorité de ces cas ont eu lieu dans 18 pays hautement prioritaires d'Europe orientale et d'Asie centrale, parmi lesquels de nombreux ont adhéré à une initiative dirigée par le Bureau régional de l'OMS pour l'Europe. L'objectif était de mettre en place trois schémas thérapeutiques modifiés plus courts de 9 mois, entièrement oraux, (mSTR, pour l'anglais "fully oral, 9-month modified shorter treatment regimens ¼) pour le traitement de la RR/MDR-TB dans le cadre d'une recherche opérationnelle. Ces trois schémas étaient les suivants 1) bédaquiline + linézolide + lévofloxacine + clofazimine + cyclosérine (BdqLzdLfxCfzCs) ; 2) BdqLzdLfxCfz + delamanid (Dlm) pour les enfants de plus de 6 ans et les adultes ; et 3) DlmLzdLfxCfz pour les enfants de moins de 6 ans. Le projet visait à améliorer l'efficacité des traitements, à faciliter l'application des mSTR, à promouvoir la qualité des soins et à renforcer les capacités de recherche, tout en contribuant aux connaissances mondiales sur l'utilisation des mSTR par voie orale. Entre avril 2020 et juin 2022, plus de 2 800 patients ont reçu un traitement par mSTR dans la Région Européenne de l'OMS. Cette expérience unique a encouragé la continuation de la collaboration avec les programmes nationaux de lutte contre la TB, les autorités sanitaires, les experts et les donateurs tant en Europe qu'à l'étranger. L'accent est mis sur la mise en œuvre de la recherche opérationnelle et l'amélioration de la qualité des soins dans les pays de la région où la TB est fortement prévalente. Nous avons détaillé les principes de l'initiative, ses avantages et ses inconvénients, dans l'espoir d'inciter d'autres pays à suivre cet exemple, tout en exposant les étapes à venir.

Evaluating newly approved drugs in combination regimens for multidrug-resistant tuberculosis with fluoroquinolone resistance (endTB-Q): study protocol for a multi-country randomized controlled trial.

BACKGROUND: Treatment for fluoroquinolone-resistant multidrug-resistant/rifampicin-resistant tuberculosis (pre-XDR TB) often lasts longer than treatment for less resistant strains, yields worse efficacy results, and causes substantial toxicity. The newer anti-tuberculosis drugs, bedaquiline and delamanid, and repurposed drugs clofazimine and linezolid, show great promise for combination in shorter, less-toxic, and effective regimens. To date, there has been no randomized, internally and concurrently controlled trial of a shorter, all-oral regimen comprising these newer and repurposed drugs sufficiently powered to produce results for pre-XDR TB patients. METHODS: endTB-Q is a phase III, multi-country, randomized, controlled, parallel, open-label clinical trial evaluating the efficacy and safety of a treatment strategy for patients with pre-XDR TB. Study participants are randomized 2:1 to experimental or control arms, respectively. The experimental arm contains bedaquiline, linezolid, clofazimine, and delamanid. The control comprises the contemporaneous WHO standard of care for pre-XDR TB. Experimental arm duration is determined by a composite of smear microscopy and chest radiographic imaging at baseline and re-evaluated at 6 months using sputum culture results: participants with less extensive disease receive 6 months and participants with more extensive disease receive 9 months of treatment. Randomization is stratified by country and by participant extent-of-TB-disease phenotype defined according to screening/baseline characteristics. Study participation lasts up to 104 weeks post randomization. The primary objective is to assess whether the efficacy of experimental regimens at 73 weeks is non-inferior to that of the control. A sample size of 324 participants across 2 arms affords at least 80% power to show the non-inferiority, with a one-sided alpha of 0.025 and a non-inferiority margin of 12%, against the control in both modified intention-to-treat and per-protocol populations. DISCUSSION: This internally controlled study of shortened treatment for pre-XDR TB will provide urgently needed data and evidence for clinical and policy decision-making around the treatment of pre-XDR TB with a four-drug, all-oral, shortened regimen. TRIAL REGISTRATION: ClinicalTrials.Gov NCT03896685. Registered on 1 April 2018; the record was last updated for study protocol version 4.3 on 17 March 2023.

Outcomes of WHO-conforming, longer, all-oral multidrug-resistant TB regimens and analysis implications.

BACKGROUND: Evidence of the effectiveness of the WHO-recommended design of longer individualized regimens for multidrug- or rifampicin-resistant TB (MDR/RR-TB) is limited.OBJECTIVES: To report end-of-treatment outcomes for MDR/RR-TB patients from a 2015-2018 multi-country cohort that received a regimen consistent with current 2022 WHO updated recommendations and describe the complexities of comparing regimens.METHODS: We analyzed a subset of participants from the endTB Observational Study who initiated a longer MDR/RR-TB regimen that was consistent with subsequent 2022 WHO guidance on regimen design for longer treatments. We excluded individuals who received an injectable agent or who received fewer than four likely effective drugs.RESULTS: Of the 759 participants analyzed, 607 (80.0%, 95% CI 77.0-82.7) experienced successful end-of-treatment outcomes. The frequency of success was high across groups, whether stratified on number of Group A drugs or fluoroquinolone resistance, and ranged from 72.1% to 90.0%. Regimens were highly variable regarding composition and the duration of individual drugs.CONCLUSIONS: Longer, all-oral, individualized regimens that were consistent with 2022 WHO guidance on regimen design had high frequencies of treatment success. Heterogeneous regimen compositions and drug durations precluded meaningful comparisons. Future research should examine which combinations of drugs maximize safety/tolerability and effectiveness.

Concordance of three approaches for operationalizing outcome definitions for multidrug-resistant TB.

BACKGROUND: The WHO provides standardized outcome definitions for rifampicin-resistant (RR) and multidrug-resistant (MDR) TB. However, operationalizing these definitions can be challenging in some clinical settings, and incorrect classification may generate bias in reporting and research. Outcomes calculated by algorithms can increase standardization and be adapted to suit the research question. We evaluated concordance between clinician-assigned treatment outcomes and outcomes calculated based on one of two standardized algorithms, one which identified failure at its earliest possible recurrence (i.e., failure-dominant algorithm), and one which calculated the outcome based on culture results at the end of treatment, regardless of early occurrence of failure (i.e., success-dominant algorithm).METHODS: Among 2,525 patients enrolled in the multi-country endTB observational study, we calculated the frequencies of concordance using cross-tabulations of clinician-assigned and algorithm-assigned outcomes. We summarized the common discrepancies.RESULTS: Treatment success calculated by algorithms had high concordance with treatment success assigned by clinicians (95.8 and 97.7% for failure-dominant and success-dominant algorithms, respectively). The frequency and pattern of the most common discrepancies varied by country.CONCLUSION: High concordance was found between clinician-assigned and algorithm-assigned outcomes. Heterogeneity in discrepancies across settings suggests that using algorithms to calculate outcomes may minimize bias.

Evaluating newly approved drugs for multidrug-resistant tuberculosis (endTB): study protocol for an adaptive, multi-country randomized controlled trial.

BACKGROUND: Treatment of multidrug- and rifampin-resistant tuberculosis (MDR/RR-TB) is expensive, labour-intensive, and associated with substantial adverse events and poor outcomes. While most MDR/RR-TB patients do not receive treatment, many who do are treated for 18 months or more. A shorter all-oral regimen is currently recommended for only a sub-set of MDR/RR-TB. Its use is only conditionally recommended because of very low-quality evidence underpinning the recommendation. Novel combinations of newer and repurposed drugs bring hope in the fight against MDR/RR-TB, but their use has not been optimized in all-oral, shorter regimens. This has greatly limited their impact on the burden of disease. There is, therefore, dire need for high-quality evidence on the performance of new, shortened, injectable-sparing regimens for MDR-TB which can be adapted to individual patients and different settings. METHODS: endTB is a phase III, pragmatic, multi-country, adaptive, randomized, controlled, parallel, open-label clinical trial evaluating the efficacy and safety of shorter treatment regimens containing new drugs for patients with fluoroquinolone-susceptible, rifampin-resistant tuberculosis. Study participants are randomized to either the control arm, based on the current standard of care for MDR/RR-TB, or to one of five 39-week multi-drug regimens containing newly approved and repurposed drugs. Study participation in all arms lasts at least 73 and up to 104 weeks post-randomization. Randomization is response-adapted using interim Bayesian analysis of efficacy endpoints. The primary objective is to assess whether the efficacy of experimental regimens at 73 weeks is non-inferior to that of the control. A sample size of 750 patients across 6 arms affords at least 80% power to detect the non-inferiority of at least 1 (and up to 3) experimental regimens, with a one-sided alpha of 0.025 and a non-inferiority margin of 12%, against the control in both modified intention-to-treat and per protocol populations. DISCUSSION: The lack of a safe and effective regimen that can be used in all patients is a major obstacle to delivering appropriate treatment to all patients with active MDR/RR-TB. Identifying multiple shorter, safe, and effective regimens has the potential to greatly reduce the burden of this deadly disease worldwide. TRIAL REGISTRATION: ClinicalTrials.gov Identifier NCT02754765. Registered on 28 April 2016; the record was last updated for study protocol version 3.3, on 27 August 2019.

Introducing new and repurposed TB drugs: the endTB experience.

In 2015, the initiative Expand New Drug Markets for TB (endTB) began, with the objective of reducing barriers to access to the new and repurposed TB drugs. Here we describe the major implementation challenges encountered in 17 endTB countries. We provide insights on how national TB programmes and other stakeholders can scale-up the programmatic use of new and repurposed TB drugs, while building scientific evidence about their safety and efficacy. For any new drug or diagnostic, multiple market barriers can slow the pace of scale-up. During 2015-2019, endTB was successful in increasing the number of patients receiving new and repurposed TB drugs in 17 countries. The endTB experience has many lessons, which are relevant to country level introduction of new TB drugs, as well as non-TB drugs and diagnostics. For example: the importation of TB drugs is possible even in the absence of registration; emphasis on good clinical monitoring is more important than pharmacovigilance reporting; national guidelines and expert committees can both facilitate and hinder innovative practice; clinicians use new and repurposed TB drugs when they are available; data collection to generate scientific evidence requires financial and human resources; pilot projects can drive national scale-up.

Global programmatic use of bedaquiline and delamanid for the treatment of multidrug-resistant tuberculosis.

SETTING: The World Health Organization recommended two new drugs, bedaquiline (BDQ) and delamanid (DLM), for the treatment of multidrug-resistant tuberculosis (MDR-TB) in 2013 and 2014, respectively. An estimated one third of patients with MDR-TB would benefit from the inclusion of these drugs in their treatment regimens. DESIGN: A convenience sample of 36 countries voluntarily reported monthly data on cumulative programmatic use of new drugs to the Drug-Resistant TB Scale-Up Treatment Action Team between 1 July 2015 and 31 June 2017. Programmatic use was defined as treatment for MDR-TB with newer drugs outside of clinical trials or compassionate use. RESULTS: A total of 10 164 persons were started on BDQ and 688 started on DLM during the reporting period. Only 15.7% of the 69 213 persons estimated to need newer drugs over the study period were reported to have received them. CONCLUSION: While there has been significant progress in some countries, uptake of the newer drugs has not kept pace with a conservative estimate of need; fewer than 20% of persons likely to benefit from either BDQ or DLM have received them. Concerted efforts are needed to ensure that the newer drugs are made available more widely for persons with MDR-TB in need of these therapeutic options.

Presumptive treatment of multidrug-resistant tuberculosis in household contacts.

SETTING: Multidrug-resistant tuberculosis (MDR-TB) is a growing global health threat that often requires presumptive treatment in the absence of drug susceptibility testing (DST) results. OBJECTIVE: To compare two approaches to the treatment of MDR-TB contacts with no DST results who develop TB disease. DESIGN: We conducted a retrospective cohort study of adults treated for TB disease who were contacts of patients living with MDR-TB. Subjects had been treated according to one of two presumptive treatment strategies: 1) regimens containing exclusively first-line drugs, and 2) regimens that included both first- and second-line drugs that were adjusted if and when DST results became available. The primary endpoint was a composite of death and treatment failure. RESULTS: Household contacts of MDR-TB patients who developed TB disease and were treated with first-line regimens were significantly more likely to experience unfavorable end-of-treatment outcomes than those treated with presumptive MDR-TB regimens (RR 2.88, 95%CI 1.24-6.68). CONCLUSION: Household contacts of MDR-TB patients who develop TB disease but have no DST results should receive regimens containing second-line drugs selected based on the infecting strain of the index patient. Regimens containing only first-line anti-tuberculosis drugs significantly increase the risk of unfavorable outcomes.

WHO guidelines for the programmatic management of drug-resistant tuberculosis: 2011 update.

The production of guidelines for the management of drug-resistant tuberculosis (TB) fits the mandate of the World Health Organization (WHO) to support countries in the reinforcement of patient care. WHO commissioned external reviews to summarise evidence on priority questions regarding case-finding, treatment regimens for multidrug-resistant TB (MDR-TB), monitoring the response to MDR-TB treatment, and models of care. A multidisciplinary expert panel used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to develop recommendations. The recommendations support the wider use of rapid drug susceptibility testing for isoniazid and rifampicin or rifampicin alone using molecular techniques. Monitoring by sputum culture is important for early detection of failure during treatment. Regimens lasting ≥ 20 months and containing pyrazinamide, a fluoroquinolone, a second-line injectable drug, ethionamide (or prothionamide), and either cycloserine or p-aminosalicylic acid are recommended. The guidelines promote the early use of antiretroviral agents for TB patients with HIV on second-line drug regimens. Systems that primarily employ ambulatory models of care are recommended over others based mainly on hospitalisation. Scientific and medical associations should promote the recommendations among practitioners and public health decision makers involved in MDR-TB care. Controlled trials are needed to improve the quality of existing evidence, particularly on the optimal composition and duration of MDR-TB treatment regimens.

Bacteriologic monitoring of multidrug-resistant tuberculosis patients in five DOTS-Plus pilot projects.

BACKGROUND: Multidrug-resistant tuberculosis programs in DOTS-Plus pilot sites in five countries. OBJECTIVES: To calculate sputum conversion time and its relationship to treatment outcome, document the frequency of culture reversions and examine concordance of smear and culture to assess the potential consequences of monitoring by smear microscopy alone. DESIGN: Retrospective cohort analysis of 1926 patients receiving individualized, second-line therapy. RESULTS: Among 1385 sputum culture-positive cases at baseline, 1146 (83%) experienced at least one culture conversion during treatment. Conversion, however, was not sustained in all patients: 201 (15%) experienced initial culture conversion and at least one subsequent culture reversion to positive; 1064 (77%) achieved sustained culture conversion. Median time to culture conversion was 3 months. Among 206 patients whose nal conversion occurred 7-18 months after the initiation of therapy, 71% were cured or had completed treatment. CONCLUSIONS: Prolonged treatment for patients with delayed conversion may be beneficial, as 71% of late converters still achieved cure or completed treatment. This has implications for programs with de ned end points for treatment failure. The interval between rst and nal conversion among patients whose initial con- version is not sustained raises concern with respect to the ongoing debate regarding duration of treatment and the definition of cure.

Treating multidrug-resistant tuberculosis in Tomsk, Russia: developing programs that address the linkage between poverty and disease.

Tuberculosis (TB) and multidrug-resistant TB (MDR-TB) are diseases of poverty. Because Mycobacterium tuberculosis exists predominantly in a social space often defined by poverty and its comorbidities--overcrowded or congregate living conditions, substance dependence or abuse, and lack of access to proper health services, to name a few--the biology of this organism and of TB drug resistance is intimately linked to the social world in which patients live. This association is demonstrated in Russia, where political changes in the 1990s resulted in increased socioeconomic inequality and a breakdown in health services. The effect on TB and MDR-TB is reflected both in terms of a rise in TB and MDR-TB incidence and increased morbidity and mortality associated with the disease. We present the case example of Tomsk Oblast to delineate how poverty contributed to a growing MDR-TB epidemic and increasing socioeconomic barriers to successful care, even when available. The MDR-TB pilot project implemented in Tomsk addressed both programmatic and socioeconomic factors associated with unfavorable outcomes. The result has been a strengthening of the overall TB control program in the region and improved case-holding for the most vulnerable patients. The model of MDR-TB care in Tomsk is applicable for other resource-poor settings facing challenges to TB and MDR-TB control.

Adverse reactions among patients being treated for MDR-TB in Tomsk, Russia.

BACKGROUND AND SIGNIFICANCE: Treatment of multidrug-resistant tuberculosis (MDR-TB) is challenging because of the toxicity of second-line medications. Little is known about whether adverse events impact treatment outcome. METHODS: We conducted a retrospective case series of 244 MDR-TB patients enrolled in Tomsk between 10 September 2000 and 10 September 2002. Adverse reactions were determined by laboratory data and/or clinical criteria. A multiple logistic regression model was performed to determine whether the occurrence of adverse reactions was associated with poor treatment outcome. RESULTS: In this cohort, 76.0% were cured, 6.6% failed, 4.9% died and 11.5% defaulted. Adverse events were observed in 73.3% of patients, occurring in 74.8% of patients who were adherent (taking at least 80% of prescribed doses) and 59.1% of non-adherent individuals (P = 0.11). The impact of adverse events on outcome was modified by non-adherence; among adherent patients, the occurrence of any adverse reaction was associated with treatment cure (adjusted odds ratio 3.24, 95% confidence interval 1.56-6.70). CONCLUSION: Adverse reactions occurred frequently in MDR-TB patients in Tomsk, Russia, but did not negatively impact treatment outcome. The occurrence of adverse reactions among adherent patients was associated with treatment cure.

Treatment outcomes in an integrated civilian and prison MDR-TB treatment program in Russia.

SETTING: Multidrug-resistant tuberculosis (MDR-TB) is a major problem in countries of the former Soviet Union in both the civilian and prison sectors. OBJECTIVE: To evaluate outcomes of the MDR-TB treatment program (DOTS-Plus) in Tomsk, Russia. DESIGN: Retrospective case series of all patients enrolled in this program between 10 September 2000 and 10 September 2002. The program involves both the civilian and penitentiary TB services in Tomsk. Poor treatment outcome was defined as death, default and treatment failure. RESULTS: Among the 244 patients who received treatment, 77% were cured, 5% died, 7% failed, and 12% defaulted. In a multivariable analysis, alcohol consumption during treatment and the presence of both cavitary and bilateral disease were found to be the strongest predictors of poor treatment outcome. CONCLUSIONS: The integration of civilian and penitentiary TB services in the Tomsk MDR-TB treatment program has resulted in high cure rates and low rates of default. However, alcohol use among patients with MDR-TB is associated with poor treatment outcomes. Better understanding and programmatic alcohol interventions are needed if large-scale treatment of MDR-TB is to be successful in areas with high rates of alcohol use disorders.

Representative drug susceptibility patterns for guiding design of retreatment regimens for MDR-TB.

BACKGROUND: There is no gold standard on how national tuberculosis programs should design retreatment regimens. Often drug susceptibility testing (DST) is not available for all patients, and representative DST patterns in patient populations are used to guide therapy. OBJECTIVES: To examine DST patterns in different patient populations based on previous treatment and to estimate the number of effective anti-tuberculosis agents in several retreatment regimens. METHODS: We reviewed DST results from patients treated with individualized regimens in Peru between January 1998 and July 2004. We stratified patients into four groups based on previous treatment exposure from Group 1 who had failed only one regimen to Group 4 who had failed three regimens. We compared resistance frequencies across the four groups. In Groups 1 and 3, the number of likely effective agents under six possible retreatment regimen scenarios was estimated. RESULTS: Resistance to second-line drugs was significantly higher in groups with more previous courses of treatment. A few retreatment regimens could be identified that would allow at least 80% of patients to receive at least four likely effective drugs. CONCLUSION: Because it is associated with resistance frequencies, previous treatment exposure can serve to guide the design of non-individualized MDR-TB regimens.

Speaking the same language: treatment outcome definitions for multidrug-resistant tuberculosis.

SETTING: Globally it is estimated that 273000 new cases of multidrug-resistant tuberculosis (MDR-TB, resistance to isoniazid and rifampicin) occurred in 2000. To address MDR-TB management in the context of the DOTS strategy, the World Health Organization and partners have been promoting an expanded treatment strategy called DOTS-Plus. However, standard definitions for MDR-TB patient registration and treatment outcomes do not exist. OBJECTIVE: To propose a standardized set of case registration groups and treatment outcome definitions for MDR-TB and procedures for conducting cohort analyses under the DOTS-Plus strategy. DESIGN: Using published definitions for drug-susceptible TB as a guide, a 2-year-long series of meetings, conferences, and correspondence was undertaken to review published literature and country-specific program experience, and to develop international agreement. RESULTS: Definitions were designed for MDR-TB patient categorization, smear and culture conversion, and treatment outcomes (cure, treatment completion, death, default, failure, transfer out). Standards for conducting outcome analyses were developed to ensure comparability between programs. CONCLUSION: Optimal management strategies for MDR-TB have not been evaluated in controlled clinical trials. Standardized definitions and cohort analyses will facilitate assessment and comparison of program performance. These data will contribute to the evidence base to inform decision makers on approaches to MDR-TB control.

Retreatment management strategies when first-line tuberculosis therapy fails.

SETTING: Public ambulatory centers in northern Lima, Peru. OBJECTIVE: To compare two retreatment strategies in Category I failures. DESIGN: Retrospective cohort study of Category I failures enrolled between February 1997 and October 2001. Strategy A was a nationwide approach, applying a Category II regimen; if that regimen failed, a standardized regimen including second-line drugs was used. Strategy B was a pilot protocol designed to diagnose and treat multidrug-resistant tuberculosis (MDR-TB); this strategy included drug susceptibility testing (DST) and eliminated the Category II regimen. RESULTS: Of 125 patients that Category I failed to cure, 73 entered Strategy A and 52 entered Strategy B. Almost 90% of those with DST results had MDR-TB. Strategy B was three times more likely than Strategy A to cure patients (79% vs. 38%, RR = 2.9, 95% CI 1.7-5.1) and five times more likely to cure patients than the Category II regimen alone (79% vs. 15%, RR 5.2, 95% CI 3.0-9.2). Strategy B also significantly reduced delays to MDR-TB diagnosis and to the initiation of MDR-TB therapy. CONCLUSIONS: Under program conditions, a retreatment strategy based on DST and eliminating the Category II regimen can improve clinical outcomes among Category I treatment failures found to have active, infectious MDR-TB.

Clinical and programmatic considerations in the treatment of MDR-TB in children: a series of 16 patients from Lima, Peru.

SETTING: Since 2000, the directly observed treatment, short-course (DOTS) strategy has been expanded in several countries to include treatment of multidrug-resistant tuberculosis (MDR-TB). This strategy is known as DOTS-Plus. Tuberculosis is a common cause of morbidity and mortality for children throughout the developing world. Children may also be infected with MDR-TB, yet most developing countries do not specifically address pediatric MDR-TB. OBJECTIVE: To present the intermediate outcomes of the first 16 children enrolled in the Peruvian DOTS-Plus program and to demonstrate the tolerability of second-line anti-tuberculosis drugs. RESULTS: Three children completed therapy and are cured, one child had bacteriologic and clinical failure after 12 months of therapy and died of respiratory insufficiency, and 12 have intermediate outcomes demonstrating favorable clinical, bacteriologic, and radiographic evidence of improvement after 9-19 months of therapy. CONCLUSIONS: Of the 16 pediatric DOTS-Plus patients, 15 have tolerated therapy well and have had favorable clinical evolution. However, the diagnosis of pediatric MDR-TB is often extremely delayed due to reliance on the adult case definition and should be changed to prevent progressive, chronic illness in such children. Programmatic changes could facilitate earlier diagnosis and treatment of pediatric MDR-TB in Peru and in other DOTS-Plus programs.

Use of a kinetic energy orifice as a probe of metastable dissociation in Fourier transform ion cyclotron resonance mass spectrometry.

Although Fourier transform ion cyclotron resonance mass spectrometry is a powerful tool in the qualitative observation of gas phase reactions, ion detection is on the millisecond time scale, orders of magnitude longer than typically found when using a sector instrument. Observations of short-lived species such as chemically activated adduct ions can be accomplished using selective ion excitation as a probe of intermediate lifetime. Whereas ion elimination has been shown to be effective in monitoring ion lifetimes on the microsecond time scale, problems associated with detecting ions produced with high kinetic energies limits the technique. Use of a kinetic energy orifice as an ion skimmer effectively eliminates ions near the center of the ion cell at relatively low kinetic energies. By modifying a single section cell to include a kinetic energy orifice, the lifetimes of chemically activated adduct ions have been investigated.

The PACE model: description and impressions of a capitated model of long-term care for the elderly.

The Program of All-Inclusive Care for the Elderly (PACE) is an innovative model of comprehensive long-term medical and social services. The system receives monthly capitation payments from Medicare and Medicaid for clients who are nursing-home eligible. PACE was developed originally by On Lok Senior Health Services in San Francisco's Chinatown in the late 1970s. PACE is based upon the concept of maintaining the independence, autonomy and dignity of frail and disabled elders nearing the end of life (Sapir, 1996). The program's underlying principle is to keep participants (PACE program enrollees) in the community for as long as it remains medically, socially, and economically feasible (Shen and Iverson, 1992). There is also a strong intention to preserve and support the older adult's family unit.

Anti-tumor vaccine adjuvant effects of IL-2 liposomes in mice immunized against MCA-102 sarcoma.

MCA-102, a murine sarcoma previously reported to be non-immunogenic in C57/BL6 murine tumor models was used in a tumor vaccine preparation which included liposome encapsulated IL-2 as an adjuvant. C57/BL6 mice were immunized in the right hind footpad with irradiated MCA-102 murine sarcoma cells on days 0, 7, and 21 with or without IL-2 liposome adjuvant at 25,000 IL-2 units/injection. Mice were challenged with live tumor in the right flank on day 35. Survival of mice given IL-2 liposomes with irradiated MCA-102 cells was significantly prolonged over mice given tumor antigen with saline, and non-immunized mice. In addition, mice which received the IL-2 liposome adjuvant also had prolonged survival over those mice immunized with the additional control adjuvants of free IL-2 or dimyristoyl phosphatidyl choline (DMPC) lipid in the form of empty liposomes. IL-2 liposome plus tumor antigen also yielded a significant local protective response against live MCA-102 tumor challenge. When live tumor was injected into the site of previous immunizations on day 21 after two immunizations, the IL-2 liposome adjuvant group showed significantly delayed local growth of tumor compared to animals immunized without adjuvant, or with the adjuvants of empty liposomes or free IL-2. Finally, immunized mice were challenged with irradiated tumor cells and saline intradermally in the ears and delayed type hypersensitivity (DTH), an indicator of helper T cell response, was measured.(ABSTRACT TRUNCATED AT 250 WORDS)