Background Congress has authorized the United States Food and Drug Administration (FDA) to provide industry sponsors with a 6-month extension of drug marketing rights under the Pediatric Exclusivity ...Provision if FDA-requested pediatric drug trials are conducted. The cost and economic return of pediatric exclusivity to industry sponsors has been shown to be highly variable. We sought to determine the cost of performing pediatric exclusivity trials within a single therapeutic area and the subsequent economic return to industry sponsors. Methods We evaluated 9 orally administered antihypertensive drugs submitted to the FDA under the Pediatric Exclusivity Provision from 1997 to 2004 and obtained key elements of the clinical trial designs and operations. Estimates of the costs of performing the studies were generated and converted into after-tax cash outflow. Market sales were obtained and converted into after-tax inflows based on 6 months of additional patent protection. Net economic return and net return-to-cost ratios were determined for each drug. Results Of the 9 antihypertensive agents studied, an average of 2 studies per drug was performed, including at least 1 pharmacokinetic study and a safety and efficacy study. The median cost of completing a pharmacokinetic trial was $862,000 (range $556,000 to 1.8 million). The median cost of performing safety and efficacy trials for these agents was $4.3 million (range $2.1-12.9 million). The ratio of net economic return to cost was 17 (range 4-64.7). Conclusion We found that, within a cohort of antihypertensive drugs, the Pediatric Exclusivity Provision has generated highly variable, yet lucrative returns to industry sponsors.
Background The benefit of a primary prevention implantable cardioverter-defibrillator (ICD) among patients with chronic kidney disease is uncertain. Study Design Meta-analysis of patient-level data ...from randomized controlled trials. Setting & Population Patients with symptomatic heart failure and left ventricular ejection fraction < 35%. Selection Criteria for Studies From 7 available randomized controlled studies with patient-level data, we selected studies with available data for important covariates. Studies without patient-level data for baseline estimated glomerular filtration rate (eGFR) were excluded. Intervention Primary prevention ICD versus usual care effect modification by eGFR. Outcomes Mortality, rehospitalizations, and effect modification by eGFR. Results We included data from the Multicenter Automatic Defibrillator Implantation Trial I (MADIT-I), MADIT-II, and the Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT). 2,867 patients were included; 36.3% had eGFR < 60 mL/min/1.73 m2 . Kaplan-Meier estimate of the probability of death during follow-up was 43.3% for 1,334 patients receiving usual care and 35.8% for 1,533 ICD recipients. After adjustment for baseline differences, there was evidence that the survival benefit of ICDs in comparison to usual care depends on eGFR (posterior probability for null interaction P < 0.001). The ICD was associated with survival benefit for patients with eGFR ≥ 60 mL/min/1.73 m2 (adjusted HR, 0.49; 95% posterior credible interval, 0.24-0.95), but not for patients with eGFR < 60 mL/min/1.73 m2 (adjusted HR, 0.80; 95% posterior credible interval, 0.40-1.53). eGFR did not modify the association between the ICD and rehospitalizations. Limitations Few patients with eGFR < 30 mL/min/1.73 m2 were available. Differences in trial-to-trial measurement techniques may lead to residual confounding. Conclusions Reductions in baseline eGFR decrease the survival benefit associated with the ICD. These findings should be confirmed by additional studies specifically targeting patients with varying eGFRs.
Abstract Objectives The aim of this study was to determine if the benefit of implantable cardioverter-defibrillators (ICDs) is modulated by medical comorbidity. Background Primary prevention ICDs ...improve survival in patients at risk for sudden cardiac death. Their benefit in patients with significant comorbid illness has not been demonstrated. Methods Original, patient-level datasets from MADIT I (Multicenter Automatic Defibrillator Implantation Trial I), MADIT II, DEFINITE (Defibrillators in Non-Ischemic Cardiomyopathy Treatment Evaluation), and SCD-HeFT (Sudden Cardiac Death in Heart Failure Trial) were combined. Patients in the combined population (N = 3,348) were assessed with respect to the following comorbidities: smoking, pulmonary disease, diabetes, peripheral vascular disease, atrial fibrillation, ischemic heart disease, and chronic kidney disease. The primary outcome was overall mortality, using the hazard ratio (HR) of time to death for patients receiving an ICD versus no ICD by extent of medical comorbidity, and adjusted for age, sex, race, left ventricular ejection fraction, use of antiarrhythmic drugs, beta-blockers, and angiotensin-converting enzyme inhibitors. Results Overall, 25% of patients (n = 830) had <2 comorbid conditions versus 75% (n = 2,518) with significant comorbidity (≥2). The unadjusted hazard of death for patients with an ICD versus no ICD was significantly lower, but this effect was less for patients with ≥2 comorbidities (unadjusted HR: 0.71; 95% confidence interval: 0.61 to 0.84) compared with those with <2 comorbidities (unadjusted HR: 0.59; 95% confidence interval: 0.40 to 0.87). After adjustment, the benefit of an ICD decreased with increasing number of comorbidities (p = 0.004). Conclusions Patients with extensive comorbid medical illnesses may experience less benefit from primary prevention ICDs than those with less comorbidity; implantation should be carefully considered in sick patients. Further study of ICDs in medically complex patients is warranted.
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