Cost-effectiveness analysis of Chlamydia trachomatis screening in Dutch pregnant women

Chlamydia trachomatis infections during pregnancy may have serious consequences for women and their offspring. Chlamydial infections are largely asymptomatic. Hence, prevention is based on screening. The objective of this study was to estimate the cost-effectiveness of C. trachomatis screening during pregnancy. We used a health-economic decision analysis model, which included potential health outcomes of C. trachomatis infection for women, partners and infants, and premature delivery. We estimated the cost-effectiveness from a societal perspective using recent prevalence data from a population-based prospective cohort study among pregnant women in the Netherlands. We calculated the averted costs by linking health outcomes with health care costs and productivity losses. Cost-effectiveness was expressed as net costs per major outcome prevented and was estimated in base-case analysis, sensitivity, and scenario analysis. In the base-case analysis, the costs to detect 1000 pregnant women with C. trachomatis were estimated at €527,900. Prevention of adverse health outcomes averted €626,800 in medical costs, resulting in net cost savings. Sensitivity analysis showed that net cost savings remained with test costs up to €22 (test price €19) for a broad range of variation in underlying assumptions. Scenario analysis showed even more cost savings with targeted screening for women less than 30 years of age or with first pregnancies only. Antenatal screening for C. trachomatis is a cost-saving intervention when testing all pregnant women in the Netherlands. Savings increase even further when testing women younger than 30 years of age or with pregnancies only.</p

Potential cost-effectiveness of a new infant tuberculosis vaccine in South Africa--implications for clinical trials: a decision analysis.

Novel tuberculosis vaccines are in varying stages of pre-clinical and clinical development. This study seeks to estimate the potential cost-effectiveness of a BCG booster vaccine, while accounting for costs of large-scale clinical trials, using the MVA85A vaccine as a case study for estimating potential costs. We conducted a decision analysis from the societal perspective, using a 10-year time frame and a 3% discount rate. We predicted active tuberculosis cases and tuberculosis-related costs for a hypothetical cohort of 960,763 South African newborns (total born in 2009). We compared neonatal vaccination with bacille Calmette-Guérin alone to vaccination with bacille Calmette-Guérin plus a booster vaccine at 4 months. We considered booster efficacy estimates ranging from 40% to 70%, relative to bacille Calmette-Guérin alone. We accounted for the costs of Phase III clinical trials. The booster vaccine was assumed to prevent progression to active tuberculosis after childhood infection, with protection decreasing linearly over 10 years. Trial costs were prorated to South Africa's global share of bacille Calmette-Guérin vaccination. Vaccination with bacille Calmette-Guérin alone resulted in estimated tuberculosis-related costs of $89.91 million 2012 USD, and 13,610 tuberculosis cases in the birth cohort, over the 10 years. Addition of the booster resulted in estimated cost savings of$7.69-$16.68 million USD, and 2,800-4,160 cases averted, for assumed efficacy values ranging from 40%-70%. A booster tuberculosis vaccine in infancy may result in net societal cost savings as well as fewer active tuberculosis cases, even if efficacy is relatively modest and large scale Phase III studies are required

Markov process used to estimate vaccination rates, acquisition of latent TB infection and active disease.

<p>Markov process used to estimate vaccination rates, acquisition of latent TB infection and active disease.</p

Sample subtree showing potential drug resistance and treatment outcomes after diagnosis of active TB disease.

<p>Sample subtree showing potential drug resistance and treatment outcomes after diagnosis of active TB disease.</p

Vaccine-Associated Costs.

<p>Cost scenarios gathered in part by interview with Oxford Emergent Tuberculosis Consortium.</p

Sample Size and Research Cost for Different Booster Vaccine Efficacy Values.

<p>Length of follow-up 2 years.</p><p> assumed active TB risk = 2% in control arm;</p><p> lower limit confidence interval set to >30%;</p><p> Power 90%;</p><p> Significance level = .05.</p><p>†The estimated cost of Phase IIB (clinical trials plus start-up costs), added to the cost of Phase III trials to give a final research and development cost.</p

Predicted Outcomes with Varying Efficacy Values for BCG+Booster Vaccine.

<p>Cost expressed in $million US 2012.</p><p>†Expressed in thousands.</p

Sensitivity Analysis.

<p>Best Case Scenario.</p><p><b>Halved</b>: Booster Vaccine Cost per Dose; Probability of TB Diagnosis; ART protection from EHIV progression.</p><p><b>Doubled</b>: Probability of Drug-Resistant TB, HIV Prevalence at Birth; Cost per DOTS visit.</p><p><b>BCG + Booster Vaccine Efficacy</b> = <b>85% relative to BCG alone.</b></p><p>†Worst Case Scenario:</p><p><b>Halved:</b> Probability of Drug-Resistant TB; HIV Prevalence at Birth; Cost per DOTS visit.</p><p><b>Doubled</b>: Booster Vaccine Cost per Dose.</p><p><b>ART</b> protection against progression from asymptomatic HIV infection to AIDS = 90%.</p><p><b>Probability</b> of TB Diagnosis = 90%.</p><p><b>BCG + Booster Vaccine Efficacy</b> = <b>30% relative to BCG alone.</b></p