Advancing pharmacovigilance through academic-legal collaboration: the case of gadolinium-based contrast agents and nephrogenic systemic fibrosis-a Research on Adverse Drug Events and Reports (RADAR) report.

OBJECTIVE: To compare and contrast three databases, that is, The International Centre for Nephrogenic Systemic Fibrosis Registry (ICNSFR), the Food and Drug Administration Adverse Event Reporting System (FAERS) and a legal data set, through pharmacovigilance and to evaluate international nephrogenic systemic fibrosis (NSF) safety efforts. METHODS: The Research on Adverse Drug events And Reports methodology was used for assessment-the FAERS (through June 2009), ICNSFR and the legal data set (January 2002 to December 2010). Safety information was obtained from the European Medicines Agency, the Danish Medicine Agency and the Food and Drug Administration. RESULTS: The FAERS encompassed the largest number (n = 1395) of NSF reports. The ICNSFR contained the most complete (n = 335, 100%) histopathological data. A total of 382 individual biopsy-proven, product-specific NSF cases were analysed from the legal data set. 76.2% (291/382) identified exposure to gadodiamide, of which 67.7% (197/291) were unconfounded. Additionally, 40.1% (153/382) of cases involved gadopentetate dimeglumine, of which 48.4% (74/153) were unconfounded, while gadoversetamide was identified in 7.3% (28/382) of which 28.6% (8/28) were unconfounded. Some cases involved gadobenate dimeglumine or gadoteridol, 5.8% (22/382), all of which were confounded. The mean number of exposures to gadolinium-based contrast agents (GBCAs) was gadodiamide (3), gadopentetate dimeglumine (5) and gadoversetamide (2). Of the 279 unconfounded cases, all involved a linear-structured GBCA. 205 (73.5%) were a non-ionic GBCA while 74 (26.5%) were an ionic GBCA. CONCLUSION: Clinical and legal databases exhibit unique characteristics that prove complementary in safety evaluations. Use of the legal data set allowed the identification of the most commonly implicated GBCA. ADVANCES IN KNOWLEDGE: This article is the first to demonstrate explicitly the utility of a legal data set to pharmacovigilance research.

Reporting of serious adverse events during cancer clinical trials to the institutional review board: an evaluation by the research on adverse drug events and reports (RADAR) project.

Global introspection is considered an unreliable method for attribution of causality of serious adverse events (SAEs), yet remains widely used for cancer drug clinical trials. Here, we compare structured case abstraction (SCA) to the routine method for detecting, evaluating, and reporting ADEs during cancer drug clinical trials to an Institutional Review Board (IRB). We obtained all SAE reports (2001-2008) received by one IRB for six clinical trials involving bevacizumab or oxaliplatin for treatment of gastrointestinal cancers. We compared the routine IRB SAE method to SCA for adverse event detection and causality attribution. Of 205 adverse events, 182 events (75%) were not reported; of these, 6 (20%) of 30 SAEs requiring an IRB report were unreported. For the 10 item Naranjo score, the amount of information useful for causality attribution was higher with SCA than the routine method (6.0 vs. 2.4 items, P < .0001). One-fifth of SAEs requiring an IRB report were unreported to the IRB via the routine method. SCA provided more useful information as to whether an SAE was caused by a cancer drug exposure. Our results suggest that SCA may improve SAE detection and the accuracy of attribution of causality during cancer drug clinical trials.

Rituximab-associated hepatitis B virus (HBV) reactivation in lymphoproliferative diseases: meta-analysis and examination of FDA safety reports.

BACKGROUND: Rituximab has been associated with hepatitis B virus reactivation (HBV-R). However, the characteristics and scope of this association remain largely undefined. METHODS: We completed a comprehensive literature search of all published rituximab-associated HBV-R cases and from the Food and Drug Administration (FDA) Adverse Event Reporting System (AERS) MedWatch database. Literature and FDA cases were compared for completeness, and a meta-analysis was completed. RESULTS: One hundred and eighty-three unique cases of rituximab-associated HBV-R were identified from the literature (n = 27 case reports, n = 156 case series). The time from last rituximab to reactivation was 3 months (range 0-12), although 29% occurred >6 months after last rituximab. Within FDA data (n = 118 cases), there was a strong signal for rituximab-associated HBV-R [proportional reporting ratio = 28.5, 95% confidence interval (CI) 23.9-34.1; Empiric Bayes Geometric Mean = 26.4, 95% CI 21.4-31.1]. However, the completeness of data in FDA reports was significantly inferior compared with literature cases (P < 0.0001). Among HBV core antibody (HBcAb(+)) series, the pooled effect of rituximab-based therapy showed a significantly increased risk of HBV-R compared with nonrituximab-treated patients (odds ratio 5.73, 95% CI 2.01-16.33; Z = 3.33, P = 0.0009) without heterogeneity (χ(2) = 2.12, P = 0.5473). CONCLUSIONS: The FDA AERS provided strong HBV-R safety signals; however, literature-based cases provided a significantly more complete description. Furthermore, meta-analysis of HBcAb(+) series identified a more than fivefold increased rate of rituximab-associated HBV-R.

Quality of methods for assessing and reporting serious adverse events in clinical trials of cancer drugs.

The validity of information regarding drug toxicity in humans depends on the quality of the methods and instruments used to assess adverse drug events (ADEs). This study evaluates the quality of instruments used to assess and report ADEs to institutional review boards (IRBs) at US cancer centers. Forms from all 49 National Cancer Institute (NCI)-designated centers were assessed for utility in abstracting event type, severity, and causality; patient demographics; safety monitoring; and consequent changes in the conduct of the relevant study. Of the 55 items considered essential for ADE reporting, one item (event description) was present on all the forms. Seventy-eight percent of the instruments prompted for global introspection of the investigator, a method known to be unreliable. Of the 34 items that our panel of experts considered essential for event description, the median number of items present was four (domain = 1-11). The use of a validated tool to describe and assess event type, severity, and causality may lead to more timely, accurate identification of safety signals in cancer treatment.

Application of software design principles and debugging methods to an analgesia prescription reduces risk of severe injury from medical use of opioids.

A prescription is a health-care program implemented by a physician or other qualified practitioner in the form of instructions that govern the plan of care for an individual patient. Although the algorithmic nature of prescriptions is axiomatic, this insight has not been applied systematically to medication safety. We used software design principles and debugging methods to create a "Patient-oriented Prescription for Analgesia" (POPA), assessed the rate and extent of adoption of POPA by physicians, and conducted a statistical process control clinical trial and a subsidiary cohort analysis to evaluate whether POPA would reduce the rate of severe and fatal opioid-associated adverse drug events (ADEs). We conducted the study in a population of 153,260 hospitalized adults, 50,576 (33%) of whom received parenteral opioids. Hospitalwide, the use of POPA increased to 62% of opioid prescriptions (diffusion half-life = 98 days), while opioid-associated severe/fatal ADEs fell from an initial peak of seven per month to zero per month during the final 6 months (P < 0.0016) of the study. In the nested orthopedics subcohort, the use of POPA increased the practice of recording pain scores (94% vs. 72%, P < 0.00001) and the use of adjuvant analgesics (95% vs. 40%, P < 0.00001) and resulted in fewer opioid-associated severe ADEs than routine patient-controlled analgesia (PCA) (0% vs. 2.7%, number needed to treat (NNT) = 35, P < 0.015). The widespread diffusion of POPA was associated with a substantial hospitalwide decline in opioid-associated severe/fatal ADEs.

Relation of plasma oxytocin and prolactin concentrations to milk production in mothers of preterm infants: influence of stress.

Responses of oxytocin and PRL to mechanical breast pumping and the influence of physiological indicators of stress were measured at 2, 4, and 6 weeks postpartum to determine potential causes of inadequate milk production in 18 women with prematurely delivered, nonnursing (<1500 g) infants. Median milk production was similar to that reported in breastfeeding mothers, but a third of mothers were producing less than half as much by week 6. Plasma oxytocin was similar to that previously reported for breastfeeding mothers. The oxytocin area under the curve (AUC) for breast-pumping sessions (70 min) was correlated at each occasion (r = 0.37, 0.58, and 0.55, respectively) with milk yield. Unlike reports of PRL levels in breast-feeding women, PRL AUC declined between weeks 2 and 6 weeks postpartum (P = 0.03); significant increases in plasma PRL occurred in response to pumping at 2 and 4 weeks, but not at 6 weeks. Salivary amylase, a measure of alpha-adrenergic activity, was highly negatively correlated on each occasion with PRL AUC (r = -0.58, -0.68, and -0.86, respectively), but not with oxytocin. Salivary cortisol was negatively correlated to a lesser degree. We hypothesize that deficiencies in preterm lactation are mediated in part upon stress-induced suppression of PRL secretion through an adrenergic mechanism.

Pharmaceutical care of postoperative nausea and vomiting: balanced scorecard for outcomes.

Using the balanced scorecard to measure outcomes, a multidisciplinary team worked to improve antiemetic therapy and decrease postoperative nausea and vomiting. Patient satisfaction measures were nausea and pain scales (10 cm, nonnumbered, visual analog). The quality measure was number of vomiting episodes. Cost measures were length of postoperative stay and antiemetic requirement. Institutional learning was assessed by spread of prescribing changes beyond the first cohort of patients. Intervention subjects were providers of general anesthesia in two cohorts of patients (60 and 346) undergoing laparoscopic cholecystectomy. Outcome assessment revealed low nausea and vomiting scores throughout the study, and antiemetic use decreased 50%. There were no deteriorations in pain scores or length of stay. Balanced scorecard measurements suggest no adverse unintended outcomes consequent to changes in prescribing behavior. Balanced scorecard processes assisted consensus among pharmacists, nurses, and physicians that may have accelerated behavioral changes.

A randomized controlled trial of filgrastim as an adjunct to antibiotics for treatment of hospitalized patients with community-acquired pneumonia. CAP Study Group.

Because of the critical role of neutrophils in host defenses, it was hypothesized that stimulation of neutrophil production and function with Filgrastim would improve the outcome of hospitalized patients with community-acquired pneumonia. To test this hypothesis, a randomized, placebo-controlled, multicenter trial of Filgrastim (300 micrograms/day up to 10 days) as an adjunct to antibiotics was conducted for these patients. Outcome measures included time to resolution of morbidity (TRM, a composite measure of temperature, respiratory rate, blood oxygenation, and chest radiograph), 28-day mortality, length of stay, and adverse events. Filgrastim increased blood neutrophils 3-fold, but TRM, mortality, and length of hospitalization were not affected. Treatment, however, accelerated radiologic improvement and appeared to reduce serious complications (e.g., empyema, adult respiratory distress syndrome, and disseminated intravascular coagulation). Filgrastim administration was safe and well tolerated in these patients. Additional trials are needed to establish the value of this approach to treatment of infectious diseases.

Ascitic fluid albumin and water flows in patients with alcoholic cirrhosis: effects of peritoneovenous shunting.

Ascites labeled albumin and water kinetics were studied at steady state by intercompartmental clearances in cirrhotic patients whose ascites volumes ranged from 6.4 to 25.2 L. In 20 patients mean (+/- SD) ascitic fluid albumin clearance (equivalent to lymphatic absorption) was 3.5 +/- 1.9 L/day. In seven of them, lymphatic absorption was 3.4 +/- 0.8 L/day, total water absorption from ascitic fluid (outflow equals inflow at steady state) was 125.8 +/- 21.5 L/day. Vascular capillary water absorption (total minus lymphatic) was 122.4 +/- 21.4 L per 24 hours. Lymphatic absorption was less than 4% of total but accounted for all albumin absorbed (13.2 +/- 6.2 gm/day). Maximum lymphatic absorption was less than 10 L per 24 hours; peritoneovenous shunting augmented this function. Mean inflow water albumin concentration was 0.11 +/- 0.06 gm/L. If plasma albumin were diluted to concentration in ascites, calculated water inflow required would be 2.82 L/day. Actual inflow was 47 times that required. The major volume outflow path was through peritoneal venous capillaries; water and small-radius solute absorption through this route increased inflow water albumin concentration to ascites level. Concurrently, whole ascitic fluid was absorbed without sieving through lymphatics. Observed ascites albumin concentration in subjects with advanced cirrhosis was produced by water absorption from a large volume of dilute solution rather than dilution of a small inflow volume, in which albumin concentration originally was hyperoncotic to ascitic fluid. Large-volume transperitoneal water diversion from sources in high-pressure, extrahepatic splanchnic capillaries to absorption through parietal nonportal, low-pressure, peritoneal venous capillaries would significantly reduce portal plasma flow into liver and have deleterious systemic hemodynamic consequences.

Particle concentration fluorescence immunoassay of gentamicin.

We report the development of a particle concentration fluorescence immunoassay (PCFIA) for gentamicin using commercially available reagents. The solid phase consists of 0.8 microns polystyrene spheres to which gentamicin antibody is noncovalently bound. Fluorescein-labeled gentamicin serves as the tracer. The assay is carried out on 96-well reaction plates and read using an automated instrument. The assay is accurate over the range of gentamicin concentrations commonly encountered in clinical practice, with day-to-day coefficients of variation of 3-7%. As little as 0.01 mg/L of gentamicin can be detected when sample predilution is omitted. PCFIA is compared with Abbott TDX fluorescence polarization immunoassay for the measurement of serum gentamicin concentrations in routine clinical specimens.

Urinary excretion of cocaine, benzoylecgonine, and ecgonine methyl ester in humans.

The excretion kinetics of cocaine (C) and its two major metabolites, benzoylecgonine (BZ) and ecgonine methyl ester (EME), were determined by collecting all urine for 30 h from 5 cocaine users (subjects C, D, E, F, and G) given bolus doses followed by exponential cocaine infusions that delivered doses of 253 (subject C), 444 (subjects D, E, and F), and 700 mg (subject G). Plasma cocaine, urine cocaine, BZ, and EME were measured by gas chromatography, with a nitrogen detector. Elimination half-times for EME and BZ, estimated from semilog plots of excretion rates vs. time, averaged 3.1 and 4.5 h respectively, in agreement with our previous report. Urinary recovery in D, E, and F was 27-41% of the dose, with 14-17% as BZ, 12-21% as EME, and 2% as cocaine. Subject C excreted very little EME--5-6-fold less than the mean for the other subjects and amounting to only 3% of the dose. Cocaine disposition in subject G, who received the largest dose and attained plasma levels of 3000 ng/mL, showed some characteristics of a nonlinear process.

Acute tolerance to cocaine in humans.

There is controversy as to whether acute tolerance develops to the principal effects of cocaine in humans. The studies described here demonstrate the phenomenon of acute tolerance to cocaine chronotropic and subjective effects and the rate and extent of tolerance development. Stable plasma cocaine concentrations were produced and then maintained in volunteer cocaine users by administering an intravenous cocaine injection followed by a cocaine infusion designed to compensate for the plasma clearance of cocaine. The euphoric effect (high) intensified to a peak at about 1 hour and then declined toward baseline at 4 hours despite the presence of constant plasma cocaine levels. The chronotropic effect reached a peak within 10 minutes and then declined, with a half-life of 31 +/- 13 (mean +/- SD) minutes toward a plateau at 33% +/- 21% of its peak intensity. Tolerance development was quantified as an exponential process, with a rate constant (tolerance factor) accounting for the progressive alteration of the cocaine concentration-effect relationship.

Theophylline distribution kinetics analyzed by reference to simultaneously injected urea and inulin.

Theophylline distribution kinetics were studied after i.v. injection in five anesthetized dogs. [14C]Urea and inulin were injected simultaneously as reference compounds to measure body fluid spaces and to calculate compartmental blood flows and permeability coefficient-surface area products for transcapillary exchange. The distribution of all three compounds was modeled with three-compartment systems in which the central compartment corresponds to intravascular space. The total volume of theophylline distribution averaged 0.72 +/- 0.09 liters/kg (+/- S.D.), indicating net tissue binding as reflected in a tissue/intracellular water partition coefficient of 1.17 +/- 0.10. Cardiac output measurements averaged 4.78 +/- 0.95 liters/min and were similar to the sum of compartmental blood flows estimated from the intercompartmental clearances of urea and inulin (4.62 +/- 1.10 liters/min) and to the sum of theophylline intercompartmental clearances (5.10 +/- 1.29 liters/min). Theophylline intercompartmental clearance to each peripheral compartment was faster than expected from its free-water diffusion coefficient and was similar to estimated compartmental blood flow. It is possible that theophylline transcapillary exchange is carrier mediated and that its rapidity contributes to the frequency of adverse reactions after i.v. administration of this drug.

Pharmacokinetic studies of highly purified human prolactin in normal human subjects.

Previous estimates of PRL pharmacokinetics have been made using radioiodinated human PRL (hPRL) infusions or by measuring serum PRL disappearance following prolactinoma resection. The recent purification of hPRL in significant quantities made it possible to measure the clearance and volume of distribution directly. Studies were also carried out to determine absorption and clearance after im injection. In five normal men whose endogenous PRL secretion was suppressed by dopamine, a loading dose of hPRL (70-90 micrograms) followed by a constant infusion (1.39-2.9 ng/min) produced steady state serum PRL levels of 15.2-25.4 ng/mL by 30-60 min. The calculated mean volume of distribution was 7.3 +/- 2.9 (+/- SD) L. The calculated MCR was 71 +/- 19 mL/min X m2, and the calculated production rate was 802 +/- 377 micrograms/24 h X m2. The plasma disappearance half-life following discontinuation of the infusion was 37 +/- 10 min. The PRL infusate consisted primarily (75.6%) of a 22.5 K dalton species, probably PRL monomer, a component eluting at 45K daltons (16.1% of the total radioimmunoreactivity), probably dimer, and a small amount of a larger mol wt species. Serum obtained during dopamine infusion but before hPRL infusion contained 68.1% of the 22.5K, 7.2% of the 45K, and 24.7% of the larger mol wt moieties. During hPRL infusion in two men there was a relative decrease in the proportion of PRL monomer to 55% and 69% and a relative increase in the PRL dimer to 33% and 18%, respectively. hPRL was injected im in doses of 1, 2, 4, and 8 micrograms/kg without prior dopamine infusion. No significant changes in serum PRL levels occurred after the 1 and 2 micrograms/kg doses (n = 5). After the 4 micrograms/kg dose (n = 8), mean serum PRL levels rose from 10.0 +/- 1.8 (+/- SEM) ng/mL to peak levels of 13.1 +/- 1.8 ng/mL (P less than 0.01). After the 8 micrograms/kg dose (n = 7), PRL levels rose from 9.3 +/- 1.6 to 16.5 +/- 1.8 ng/mL (P less than 0.01). The PRL rise began between 60 and 80 min after injection; peak levels occurred at 160-180 min. In two men given 8 micrograms/kg who were sampled for an additional 3 h, PRL levels peaked at 200-220 min and began to fall by 220-240 min, but had not returned to baseline by 6 h. There were no side-effects of PRL administration, although the 8 micrograms/kg dose caused transient local discomfort.(ABSTRACT TRUNCATED AT 400 WORDS)

Effect kinetics of N-acetylprocainamide-induced QT interval prolongation.

We attempted to correlate clinical response with the effects of N-acetylprocainamide (NAPA) on the QT interval in five patients with stable chronic ventricular arrhythmias. A 15 mg/kg dose of NAPA was administered and a pharmacokinetic-pharmacodynamic model was used to relate plasma NAPA concentrations to changes in corrected QT interval (QTc). NAPA volume of distribution, elimination clearance, and elimination half-life averaged 1.37 +/- 0.19 L/kg, 174 +/- 63 ml/min, and 8.2 +/- 1.4 hours, respectively (mean +/- SD), and NAPA renal clearance averaged 1.9 +/- 0.6 times creatinine clearance. QTc prolongation was characterized by a linear-effect model in the first four patients and averaged 2.4 msec for every microgram per milliliter NAPA in a hypothetic biophase. QTc prolongation in patient 5 was exaggerated and was analyzed with an Emax model. Nonetheless, NAPA did not control this patient's arrhythmia. Conversely, patient 1 subsequently developed torsade de pointes even though QTc prolongation in this patient was comparable to that in patients 2 through 4, who responded satisfactorily to NAPA. We conclude that QT interval changes during initial NAPA administration do not reliably predict subsequent clinical response.

Effects of changing salt and water balance on renal kallikrein, kininogen and kinin.

The kallikrein-kininogen-kinin system (KKK) has been implicated in the renal sodium excretion response to changes in dietary sodium. However, both increases and decreases in the activity of this system have been observed when urinary sodium excretion is augmented by a variety of maneuvers. To further evaluate the potential physiologic role of this system, we measured three components of the KKK system in urine. Total kallikrein, intact kininogen, and kinin were measured twice in normal individuals during balance on both a high (250 mEq/day) or low (10 mEq/day) sodium intake. A consistent and significant reduction in the activity of all three components of the KKK system was noted during the high salt intake. Furthermore, during the high sodium intake, further acute reductions in components of this system were observed when an acute saline but not water load was administered. The consistent response of the various components of the KKK system to both acute and chronic sodium loading suggests that the system is physiologically linked to the regulation of sodium balance. However, the directional changes argue against a primary natriuretic effect of this system.