Robbin F. Itzler

Interpreting Indirect Treatment Comparisons and Network Meta-Analysis for Health-Care Decision Making: Report of the ISPOR Task Force on Indirect Treatment Comparisons Good Research Practices: Part 1

Evidence-based health-care decision making requires comparisons of all relevant competing interventions. In the absence of randomized, controlled trials involving a direct comparison of all treatments of interest, indirect treatment comparisons and network meta-analysis provide useful evidence for judiciously selecting the best choice(s) of treatment. Mixed treatment comparisons, a special case of network meta-analysis, combine direct and indirect evidence for particular pairwise comparisons, thereby synthesizing a greater share of the available evidence than a traditional meta-analysis. This report from the ISPOR Indirect Treatment Comparisons Good Research Practices Task Force provides guidance on the interpretation of indirect treatment comparisons and network meta-analysis to assist policymakers and health-care professionals in using its findings for decision making. We start with an overview of how networks of randomized, controlled trials allow multiple treatment comparisons of competing interventions. Next, an introduction to the synthesis of the available evidence with a focus on terminology, assumptions, validity, and statistical methods is provided, followed by advice on critically reviewing and interpreting an indirect treatment comparison or network meta-analysis to inform decision making. We finish with a discussion of what to do if there are no direct or indirect treatment comparisons of randomized, controlled trials possible and a health-care decision still needs to be made.

Conducting indirect-treatment-comparison and network-meta-analysis studies: Report of the ISPOR task force on indirect treatment comparisons good research practices: Part 2

Evidence-based health care decision making requires comparison of all relevant competing interventions. In the absence of randomized controlled trials involving a direct comparison of all treatments of interest, indirect treatment comparisons and network meta-analysis provide useful evidence for judiciously selecting the best treatment(s). Mixed treatment comparisons, a special case of network meta-analysis, combine direct evidence and indirect evidence for particular pairwise comparisons, thereby synthesizing a greater share of the available evidence than traditional meta-analysis. This report from the International Society for Pharmacoeconomics and Outcomes Research Indirect Treatment Comparisons Good Research Practices Task Force provides guidance on technical aspects of conducting network meta-analyses (our use of this term includes most methods that involve meta-analysis in the context of a network of evidence). We start with a discussion of strategies for developing networks of evidence. Next we briefly review assumptions of network meta-analysis. Then we focus on the statistical analysis of the data: objectives, models (fixed-effects and random-effects), frequentist versus Bayesian approaches, and model validation. A checklist highlights key components of network meta-analysis, and substantial examples illustrate indirect treatment comparisons (both frequentist and Bayesian approaches) and network meta-analysis. A further section discusses eight key areas for future research.

The Incidence of Herpes Zoster in a United States Administrative Database

BACKGROUND: Few recent studies have reported data on the incidence of herpes zoster (HZ) in U.S. general clinical practice.OBJECTIVE: To estimate the age- and sex-specific incidence of HZ among U.S. health plan enrollees.DESIGN: Data for the years 2000 to 2001 were obtained from the Medstat MarketScan database, containing health insurance enrollment and claims data from over 4 million U.S. individuals. Incident HZ cases were identified through HZ diagnosis codes on health care claims. The burden of HZ among high-risk individuals with recent care for cancer, HIV, or transplantation was examined in sub-analyses. Overall incidence rates were age- and sex-adjusted to the 2000 U.S. population.PARTICIPANTS: MarketScan U.S. health plan enrollees of all ages.MEASUREMENTS AND MAIN RESULTS: We identified 9,152 incident cases of HZ (3.2 per 1,000 person-years) (95% confidence interval [CI], 3.1 to 3.2 per 1,000]. Annual HZ rates per 1,000 person-years were higher among females (3.8) than males (2.6) (P<.0001). HZ rates rose sharply with age, and were highest among individuals over age 80 (10.9 per 1,000 person-years) (95% CI, 10.2 to 11.6). The incidence of HZ per 1,000 person-years among patients with evidence of recent care for transplantation, HIV infection, or cancer (10.3) was greater than for individuals without recent care for these conditions (3.0) (P<.0001).CONCLUSIONS: The overall incidence of HZ reported in the present study was found to be similar to rates observed in U.S. analyses conducted 10 to 20 years earlier, after age- and sex-standardizing estimates from all studies to the 2000 U.S. population. The higher rate of HZ in females compared with males contrasts with prior U.S. studies.

Safety and efficacy of the pentavalent human-bovine (WC3) reassortant rotavirus vaccine in healthy premature infants.

Background: Premature infants seem to be at greater risk of hospitalization from rotavirus gastroenteritis than term infants. Safety and efficacy of the pentavalent human-bovine (WC3) reassortant rotavirus vaccine were assessed in premature infants enrolled in the large-scale, blinded, placebo-controlled rotavirus efficacy and safety trial (REST). Methods: Healthy infants 6–12 weeks of chronologic age at study entry were randomized to receive 3 oral doses of pentavalent rotavirus vaccine or placebo at 4- to 10-week intervals. Infants born at ≤36 weeks of gestational age were eligible if thriving at the time of enrollment. Safety and efficacy were retrospectively assessed in these premature infants comparing vaccine with placebo recipients. Cases of rotavirus gastroenteritis were defined as forceful vomiting and/or ≥3 watery or looser-than-normal stools within a 24-hour period, accompanied by detection of rotavirus antigen in the stool. Results: A total of 2070 infants between 25 and 36 gestational weeks received at least 1 dose of vaccine or placebo; 1005 vaccine recipients and 1061 placebo recipients were evaluable for safety. Serious adverse events occurred in 55 vaccine recipients (5.5%) and 62 placebo recipients (5.8%). In a nested substudy of 308 premature infants evaluable for detailed safety (154 in each group), the frequencies of fever, diarrhea, vomiting, and irritability were comparable between vaccine and placebo recipients. Overall, 3 doses of the pentavalent vaccine reduced the rate of hospitalizations and emergency department visits in premature infants due to rotavirus gastroenteritis by 100% (95% CI: 82.2–100) compared with placebo. The vaccine also prevented 73.0% (95% CI: −2.2–95.2) of rotavirus gastroenteritis cases of any severity. Conclusions: In this post hoc analysis of healthy premature infants, the pentavalent rotavirus vaccine was generally well-tolerated and substantially reduced rotavirus-attributable hospitalizations and emergency department visits compared with placebo. Overall, vaccine safety and efficacy seemed to be generally comparable to the results in the REST study population as a whole. These results support vaccinating healthy premature infants on the same schedule as term infants.

RotaTeq, a pentavalent rotavirus vaccine: efficacy and safety among infants in Europe

A pentavalent human-bovine reassortant oral rotavirus vaccine, RotaTeq, was evaluated among nearly 70,000 infants in the Rotavirus Efficacy and Safety Trial (REST), of which 30,523 were from Europe. All infants were followed for serious adverse events as well as hospitalizations and emergency department (ED) visits. All adverse events, health care utilization, and RVGE regardless of severity were evaluated in the clinical efficacy cohort (N=2686) in Finland. RotaTeq was 98.3% (95% CI, 90.2-100%) and 68.0% (95% CI 60.3-74.4%) efficacious against severe rotavirus gastroenteritis (RVGE) and all RVGE due to any serotype for two rotavirus seasons post-vaccination. The combined rate of hospitalizations and ED visits due to RVGE of any serotype was reduced by 94.5% (95% CI, 91.3-96.8%) for up to 2 years after vaccination. There were no statistically significant differences between RotaTeq and placebo for any of the safety outcomes. In Europe, RotaTeq was highly efficacious and well tolerated.

Efficacy of a pentavalent rotavirus vaccine in reducing rotavirus-associated health care utilization across three regions (11 countries)

OBJECTIVE To evaluate the effect of a human-bovine reassortant pentavalent rotavirus vaccine (PRV) on health care encounters in nearly 70 000 subjects randomized in three regions - Europe, the United States, and Latin America/the Caribbean - in the Rotavirus Efficacy and Safety Trial (REST). METHODS Healthy 6- to 12-week-old infants received 3 doses of PRV or placebo at 4- to 10-week intervals. The exact binomial method for ratios of Poisson counts was used to evaluate the effect of PRV on the rate of rotavirus-related hospitalizations and emergency department (ED) visits involving rotavirus G-types 1-4 occurring > or =14 days after the third dose of vaccine for up to 2 years. RESULTS In fully vaccinated infants, reductions in rotavirus-associated hospitalizations and ED visits were 94.7% (95% CI: 90.9, 96.9) in Europe, 94.9% (95% CI: 84.0, 98.9) in the United States, and 90.0% (95% CI: 29.4, 99.8) in the Latin American/Caribbean regions. CONCLUSIONS PRV reduced hospitalizations and ED visits within each region in REST. Results were consistent across regions and across the overall study cohort.

Health Care Utilization and Cost Burden of Herpes Zoster in a Community Population

OBJECTIVE To conduct a population-based study to assess health care utilization (HCU) and costs associated with herpes zoster (HZ) and its complications, including postherpetic neuralgia (PHN) and nonpain complications, in adults aged 22 years and older. PATIENTS AND METHODS Medical record data on HCU were abstracted for all confirmed new cases of HZ from January 1, 1996, through December 31, 2001, among residents of Olmsted County, Minnesota. Herpes zoster-related costs were estimated by applying the Medicare Payment Fee Schedule to health care encounters and mean wholesale prices to medications. All costs were adjusted to 2006 US dollars using the medical care component of the Consumer Price Index. RESULTS The HCU and cost of the 1669 incident HZ cases varied, depending on the complications involved. From 3 weeks before to 1 year after initial diagnosis, there were a mean of 1.8 outpatient visits and 3.1 prescribed medications at a cost of

Incremental 1-Year Medical Resource Utilization and Costs for Patients with Herpes Zoster from a Set of US Health Plans

720 for cases without PHN or nonpain complications compared with 7.5 outpatient visits and 14.7 prescribed medications at a cost of

Acute/Subacute Herpes Zoster

3998 when complications, PHN, or nonpain complications were present. CONCLUSION The annual medical care cost of treating incident HZ cases in the United States, extrapolated from the results of this study in Olmsted County, is estimated at

Cost-effectiveness of introducing a rotavirus vaccine in developing countries: The case of Mexico

1.1 billion. Most of the costs are for the care of immunocompetent adults with HZ, especially among those 50 years and older.