[Randomized clinical trial investigating three chemoprophylaxis regimens for latent tuberculosis infection in HIV-infected patients]. Latent tuberculosis infection treatment for prison inmates: a randomised controlled trial. Randomised controlled trial of isoniazid preventive therapy in South African adults with advanced HIV disease. Twice weekly tuberculosis preventive therapy in HIV infection in Zambia. Long-term effect of preventive therapy for tuberculosis in a cohort of HIV-infected Zambian adults. [Randomized trial of three regimens to prevent tuberculosis in HIV-infected patients with anergy]. [Compliance and tolerance of new antitubercular short-term chemopreventive regimens in childhood--a pilot project]. A controlled trial of 3-month, 4-month, and 6-month regimens of chemotherapy for sputum-smear-negative pulmonary tuberculosis. Results at 5 years. Hong Kong Chest Service/Tuberculosis Research Centre, Madras/British Medical Research Council. [Daily ultrashort chemotherapy and intermittent short-term chemotherapy with 4 drugs of communicable pulmonary tuberculosis treated for the first time. Results of a cooperative multicenter study].
To evaluate the adherence to, and safety of three chemoprophylaxis regimens for latent tuberculosis (TB) infection in HIV-infected patients with a positive tuberculin skin test.
                A randomized, comparative, open clinical assay was carried out in 316 HIV-infected patients in 12 Spanish hospitals. Patients were randomly assigned to one of three regimens, 108 to isoniazid for six months (6H), 103 to rifampin and isoniazid for three months (3RH), and 105 to rifampin and pyrazinamide for two months (2RZ). After completion of treatment, patients were followed-up for two years.
                The period of observation following completion of treatment was 115, 108 and 101 person-years for 6H, 3RH and 2RZ, respectively. Twenty-seven percent of patients voluntarily abandoned chemoprophylaxis and 9.7% were withdrawn due to adverse side-effects or interactions. Seven patients were withdrawn due to hepatotoxicity (5 in 6H, 2 in 3RH and 0 in 2RZ). No appreciable differences were found among the three regimens. There were 11 cases of tuberculosis during follow-up. The TB rates (cases per 100 person-years) in the three treatment groups were 3.48 in 6H, 4.63 in 3RH and 1.98 in 2RZ. With respect to 2RZ, the relative risk for TB in the 6H and 3RH regimens was 1.76 and 2.34, respectively.
                The safety of the 2RZ regimen for prophylaxis of latent TB infection in HIV patients was similar to that of the 6H and 3RH regimens. The incidence of hepatotoxicity was not higher in patients who received 2RZ. A prison in northern Taiwan.
                To compare safety and the completion rate of the 4-month daily rifampicin regimen (4R) vs. the standard 6-month daily isoniazid regimen (6H) for latent tuberculosis infection (LTBI) in prison inmates.
                This was an open-label randomised trial among human immunodeficiency virus negative male inmates. Inmates without active tuberculosis (TB) who tested positive for both the tuberculin skin test and QuantiFERON®-TB Gold In-Tube were eligible, but those with baseline glutamic pyruvic transaminase (GPT) levels ≥ 120 U/l, bilirubin levels ≥ 2.4 U/l or a platelet count < 150 k/mm(3) were excluded. The primary endpoint was any adverse event that resulted in discontinuation of LTBI treatment.
                Participants (n = 373; 14% hepatitis B surface antigen positive, 21% anti-hepatitis C virus [HCV] positive) were randomised (stratified by hepatitis B virus, HCV status and 2-year prison term) to receive either 4R or 6H under directly observed treatment. The 4R group (n = 190) was less likely to experience an adverse event leading to discontinuation of treatment (2% vs. 12%, P < 0.001 for all adverse events; 0% vs. 8%, P < 0.001 for hepatotoxicity), and more likely to complete LTBI treatment (86% vs. 78%, P = 0.041), compared with the 6H group (n = 183).
                4R is safer and has a higher completion rate than 6H as treatment for LTBI among male prison inmates. Tuberculosis (TB) preventive therapy is not effective in human immunodeficiency virus (HIV) infected adults with negative tuberculin skin tests (TSTs). However, there are insufficient data on patients with advanced HIV disease from high TB incidence areas.
                We conducted a randomised, double-blind, controlled trial comparing isoniazid (INH) with placebo among TST-negative adults with World Health Organization Stage 3 or 4 HIV disease. INH/placebo was administered for 12 months by patient-nominated supervisors. TST-positive participants were given open-label INH. Participants, who did not have access to antiretroviral therapy (ART), were followed up for 24 months with 6-monthly sputum culture and chest radiography.
                A total of 118 participants were enrolled: TST was negative in 98. In the randomised arms, the incidence of TB was 18/100 person-years (py) in the INH arm and 11.6/100 py in the placebo arm (hazard ratio 1.59, 95%CI 0.57-4.49). There were no significant differences in mortality, hospitalisation rate or CD4+ lymphocyte decline. INH/placebo adherence was 85%, and was significantly higher among participants with work-based treatment supervisors.
                We did not find any association between INH preventive therapy and reductions in incident TB among TST-negative adults with advanced HIV disease, but the study had limited statistical power. High levels of adherence were observed with patient-nominated supervisors. A randomized double-blind placebo-controlled trial was conducted to estimate the efficacy of preventive therapy for tuberculosis (TB) in HIV-infected adults in Lusaka, Zambia. The main outcome measures were the incidence of TB, mortality and adverse drug reactions.
                During a 2 year period, 1053 HIV-positive individuals without evidence of clinical TB were randomly assigned to receive 6 months of isoniazid twice a week (H), or 3 months of rifampicin twice a week (R) plus pyrazinamide (Z), or a placebo. Therapy was taken twice a week and was self administered. Subjects presenting with symptoms during the follow-up period were investigated for TB.
                The 1053 subjects in the study were followed up for a total of 1631 person-years (median = 1.8 years). Twenty-nine subjects were taken off treatment as a result of adverse drug reactions. A total of 96 cases of TB/probable TB (59 TB and 37 probable TB) were diagnosed during the study period and 185 deaths were reported. One hundred and fifteen subjects (11%) did not return to the study clinic at any time after enrolment. The incidence of TB was lower in those subjects on preventive therapy (H and RZ groups combined) compared with those on placebo (rate ratio = 0.60, 95% CI: 0.36-1.01, P = 0.057), as was the incidence of TB/probable TB (rate ratio = 0.60, 95% CI: 0.40-0.89, P = 0.013). The effect of preventive therapy was greater in those with a tuberculin skin test (TST) of 5 mm or greater, in those with a lymphocyte count of 2x10(9)/l or higher, and in those with haemoglobin of 10 g/dl or higher. There was no difference in mortality rates between the preventive therapy and placebo groups. The effect of preventive therapy declined after the first year of the study so that by 18 months the rates of TB in the treated groups were similar to that in the placebo group.
                This study has demonstrated that preventive therapy with either twice weekly isoniazid for 6 months or a combination of rifampicin and pyrazinamide for 3 months reduced the incidence of TB in HIV-infected persons in Zambia. No effect was observed on mortality. The effect was greatest in persons who had a positive TST or a lymphocyte count of 2x10(9)/l or greater, indicating that preventive therapy may be more effective in people with less advanced immunosuppression. The limited duration of the protective effect reported in this study raises the question of the need for lifelong preventive therapy or re-prophylaxis. To determine the long-term effect of preventive therapy (PT) for tuberculosis on the rates of tuberculosis, mortality and HIV progression.
                In a randomized controlled trial, 1053 HIV-positive Zambian adults received isoniazid (H) for 6 months, rifampicin plus pyrazinamide (RZ) for 3 months, or a placebo. CD4 percentage, neopterin, absolute lymphocyte count and haemoglobin were measured from enrolment (absolute CD4 cell counts from 12 months after enrolment). Because PT reduced the incidence of tuberculosis, eligible placebo subjects were offered H. Here, tuberculosis and mortality rates are compared in the three original arms (intention to treat) using data beyond the end of the trial (average follow-up 3 years; maximum 7 years).
                There were 102 cases of tuberculosis and 281 deaths (rates 3.6 and 9.0/100 person-years, respectively). There was no significant difference between the tuberculosis rates in the H and RZ groups at any time. The effect of H/RZ on tuberculosis diminished over time (P = 0.011) but the cumulative risk of tuberculosis in the first 2.5 years was significantly lower in the H/RZ group than the placebo group (rate ratio 0.55; 95% confidence interval 0.32-0.93; P = 0.028). There was no significant effect of PT on mortality or progression markers. Tuberculosis was associated with an increased mortality (adjusted rate ratio 1.96; 95% confidence interval 1.21-3.18; P = 0.006).
                Both PT regimens protect against tuberculosis for at least 2.5 years but appear to have no effect on HIV progression or mortality. These results may be used in cost-effectiveness models of PT. To evaluate the efficacy of three regimens of prophylactic therapy for tuberculosis in HIV-infected patients with anergy.
                Prospective, multi-center, randomized, comparative, and open clinical trial. Anergy was defined as absence of induration in response to three antigens (PPD, Candida albicans and parotiditis antigen) applied by the Mantoux method. Patients were randomized into one of the following prophylactic treatment groups: isoniazid for six months (6H), rifampin plus isoniazid for three months (3RH), rifampin plus pyrazinamide for two months (2RZ) or no treatment (NT). After completion of treatment, patients were followed up for two years.
                A total of 319 patients were included in the study, 83 in the 6H regimen, 82 in 3RH, 77 in 2RZ and 77 in NT. The observation period following treatment was 88, 96, 81 and 126 person-years, respectively, for 6H, 3RH, 2RZ and NT. There were 11 cases of tuberculosis during the follow-up period. The tuberculosis rates (cases per 100 person-years) were 3.4, 3.1, 1.2 and 3.1 for 6H, 3RH, 2RZ and NT respectively, with relative risks in regimens 6H, 3RH and 2RZ with respect to NT of 1.07 (0.24-4.80), 0.98 (0.22-4.4) and 0.39 (0.04-3.48), all statistically non-significant. Twenty-nine patients died during the follow-up period, none due to tuberculosis, and no appreciable differences were found among the groups.
                The results showed no significant decrease in the risk of developing tuberculosis with any of the evaluated regimens and, therefore, do not support the use of antituberculosis chemoprophylaxis in anergic HIV-infected patients. Efficacy of preventive chemotherapy in tuberculosis-infected children depends to a great extend on medical compliance and drug tolerability. Two new short-course chemoprevention-regimes of tuberculosis--four months Rifampin (A) and two months Rifampin plus Pyrazinamide (B)--were compared with the well established regimen of six months Isoniacid (C). 150 children (mean age 3.6 years with Tb conversion) were randomly allocated to these three regimens. 13 patients were non-compliant, in terms of interview, urinary INH-test strips, urine colour and prescription frequency: 7 in group C and 3 in group A and B, respectively. Adverse effects were observed in 5 patients: 3 in group C and 1 in group A and B. 1 child (group B) developed tuberculosis two years after stopping short course chemoprevention. Good compliance (94%) as well as neglectable risks of adverse effects (2%) justify further controlled studies to evaluate the efficacy of short course chemoprevention in childhood. Of 1,710 Chinese patients with radiologically active pulmonary tuberculosis but with sputum negative for acid-fast bacilli on four or more initial microscopic examinations who were studied for 5 yr, 592 (35%) had one or more initial sputum cultures positive for Mycobacterium tuberculosis. These 592 patients were randomly allocated to receive streptomycin, isoniazid, rifampin, and pyrazinamide daily for 4 months or 3 times a week for either 4 or 6 months. The remaining 1,118 patients with all their initial cultures negative were randomly allocated to receive the same four drugs daily for 3 months or 3 times a week for either 3 or 4 months. There were no bacteriologic failures during chemotherapy, and the relapse rates for the 4-month regimens during the 5 yr were 2% in 293 patients with drug-susceptible cultures initially (95% confidence limits, 1 to 5%); 8% in 59 patients with cultures resistant to isoniazid, streptomycin, or both drugs, but susceptible to rifampin initially; and 4% in 325 patients with all their cultures negative initially (95% confidence limits, 1 to 7%). The combined relapse rate for the 3-month regimens was 7% in 709 patients with all their cultures negative initially (95% confidence limits, 5 to 9%). In Hong Kong, 4 months of chemotherapy is now used routinely in the treatment of patients with smear-negative pulmonary tuberculosis, whether their initial sputum cultures are positive or negative. Three short-course regimens, all comprising isoniazide (H), rifampicine (R), streptomycine (S) and pyrazinamide (Z), are compared in a randomized prospective cooperative clinical trial. The drugs are given daily in a 3-month regimen (3-HRSZ), twice a week in a 6-month regimen (6-HRSZ2), and in a further two-phase 6-month regimen the 4 drugs are administered 3 times a week for the first 3 months followed by the administration of HSZ twice a week (without R) for further 3 months (3-HRSZ3/3-HSZ2). The number of patients admitted to study is 80, 144 and 139 respectively. The 3-month regimen has been stopped because of a high rate of relapses. 17 p.c. of the patients admitted have to be excluded from analysis for various reasons, out of these 5.8 p.c. because of adverse reactions. Two thirds of the patients had heavily positive sputum cultures at the start. 300 patients completed therapy. At the end of therapy cultures were negative in 94 p.c., 100 p.c. and 99 p.c. respectively. The rate of bacteriological relapses is 19 p.c. in 3-HRSZ, 9 p.c. in 3-HRSZ3/3-HSZ2 and 3 p.c. in 6-HRSZ2, during a follow-up period of 3-4 years after completing therapy. The acceptability was good in all treatment groups. Adverse reactions like "flu" were rarely observed. Increased blood urea was common but in general without clinical symptoms. Elevation of ALAT and ASAT was relatively frequent but mostly transient and without clinical importance. The results served as basis for the new "Recommendation for Treatment of Tuberculosis" and are interpreted with regard to practical consequences and possibilities for further rationalisation of treatment.
Treatment of latent tuberculosis infection reduces the risk of active TB in HIV positive individuals especially in those with a positive tuberculin skin test. The choice of regimen will depend on factors such as availability, cost, adverse effects, adherence and drug resistance. Future studies should assess these aspects. In addition, trials evaluating the long-term effects of anti-tuberculosis chemoprophylaxis, the optimal duration of TB preventive therapy, the influence of level of immunocompromise on effectiveness and combination of anti-tuberculosis chemoprophylaxis with antiretroviral therapy are needed.