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S S Ellenberg

Publications and source records attributed to S S Ellenberg.

At least 19 recordsLinked to original sources
PubMed1998

Comparative safety of two recombinant hepatitis B vaccines in children: data from the Vaccine Adverse Event Reporting System (VAERS) and Vaccine Safety Datalink (VSD).

BACKGROUND: Preliminary review of data from the Vaccine Adverse Event Reporting System (VAERS), 1991-1994, revealed that more serious adverse events were reported in children who received a specific brand of recombinant hepatitis B (HepB) vaccine. OBJECTIVE: To compare the post-marketing safety experience of the two recombinant HepB vaccines licensed for use in infants and children in the United States. DESIGN: Review of a case series derived from passive surveillance data in the national VAERS. A retrospective cohort study using data from one health maintenance organization participating in Vaccine Safety Datalink (VSD), a computerized record linkage system. POPULATIONS STUDIED: U.S. children, ages birth-10 years for whom adverse events after HepB vaccine were reported to VAERS, 1991-1994. Children, ages birth-6 years, who received HepB vaccine at Kaiser Permanente Medical Care Program, Northern California, 1991-1994. MAIN OUTCOME MEASURES: VAERS reporting rates for each vaccine by manufacturer were calculated from the numbers of reported events occurring within 30 days of HepB vaccination and the number of doses distributed by the manufacturers. VSD event rates for each vaccine were calculated from the numbers of hospitalization or emergency room visits within 30 days of HepB vaccination and the number of vaccine doses administered to the cohort. RESULTS: In VAERS, higher rates of serious events (i.e., life threatening or resulting in hospitalization or permanent disability) were reported in children who received Vaccine A vs. Vaccine B (relative risk [RR]: 3.13-8.18, P < 0.01), particularly by those vaccinated in the private (RR: 7.62-28.58, P < 0.01), but not public sector (RR: 2.12, P = 0.19). Similar types of events were reported in recipients of both vaccines. In contrast, analysis of VSD data showed no significant difference in rates of hospitalization or ER visits in children who received either HepB vaccine (RR: 0.96-1.25, P > 0.05). CONCLUSIONS: Our investigation reveals that it is unlikely there is a true difference between rates of serious events temporally associated with the two HepB vaccines in children. This study demonstrates the dual roles played by VAERS and VSD in providing a more complete picture of the post-marketing safety profile of childhood vaccines, and underscores the importance of using other analytic studies to evaluate findings from passive surveillance systems of adverse events.

Adverse Drug Reaction Reporting Systems↗
PubMed1998

Report of a US public health service workshop on hypotonic-hyporesponsive episode (HHE) after pertussis immunization.

Hypotonic-hyporesponsive episode (HHE) is a term used to describe a somewhat heterogenous group of clinical disorders that have been reported primarily in association with whole-cell pertussis vaccination. A 1991 review by the Institute of Medicine determined that the evidence available was indeed consistent with a causal relation between whole-cell pertussis-diphtheria-tetanus immunization and HHE, but that the evidence was insufficient to indicate a causal relationship between HHE and the subsequent development of permanent neurologic damage. More recent data from clinical trials conducted in Europe suggest that HHE also occurs after vaccination with acellular pertussis vaccines. The US Food and Drug Administration, in collaboration with the US Public Health Service, sponsored a workshop on HHE in Rockville, Maryland, on June 19, 1997. The primary goals of the workshop were to develop a case definition of HHE and to evaluate the general design and feasibility of possible studies of HHE using the federal Vaccine Adverse Event Reporting System (VAERS), a national passive surveillance system. The goals of such studies would be to understand better the acute HHE event and to evaluate the possibility of long-term sequelae. Case Definition. There has been no generally accepted definition of HHE, and a standard definition would be useful for vaccine safety work and would potentially facilitate interstudy comparisons of the growing number of licensed vaccines containing acellular pertussis components. The workshop defined HHE as an event of sudden onset occurring within 48 hours of immunization, with duration of the episode ranging from 1 minute to 48 hours, in children younger than 10 years of age. All of the following must be present: 1) limpness or hypotonia, 2) reduced responsiveness or hyporesponsiveness, and 3) pallor or cyanosis or failure to observe or to recall skin coloration. HHE is not considered to have occurred if there is a known cause for these signs (eg, postictal), if urticaria is present during the event, if normal skin coloration is observed throughout the episode, or if the child is simply sleeping. This inclusive (sensitive) case definition will allow investigators, through the technique of stratification according to certain characteristics (eg, time from vaccination to onset of HHE), to attempt to hone the definition and make it more specific. Refinement of the definition of HHE has been hindered by the lack of information on its pathophysiology and by the lack of pathognomonic signs, symptoms, and diagnostic tests. Another hindrance is that by the time the child presents for medical evaluation, the signs of HHE often have normalized. Moreover, different mechanisms may be involved in different individuals whose events meet this workshop's HHE definition. Further Study of HHE. Probably the most important question about HHE is whether it has any permanent sequelae. The workshop assessed the possible contribution VAERS-based studies could make to answering this question and found substantial methodologic problems; however, ongoing studies in Sweden and The Netherlands have the potential to provide useful information on this question. The most useful contribution of VAERS data would be in a descriptive study of HHE, with a possible case-control study of factors that may affect the risk of HHE after vaccination, rather than a study of possible permanent sequelae. The workshop participants felt that a detailed descriptive study of approximately 100 HHE events reported during a 1- to 2-year period could provide a more in-depth description of HHE cases in greater numbers than has been published previously, but the study would not address the issue of long-term sequelae of HHE. Better descriptive data may lead to new hypotheses concerning risk factors, etiology, and pathophysiology of HHE that might be evaluated further by studying subsequent cases and controls from VAERS or from other sources, depending on the hypoth

Adverse Drug Reaction Reporting Systems↗
PubMed1997

HIV vaccines.

Explore the source record for details and available documents.

AIDS Vaccines↗
PubMed1997

Syncope after immunization.

OBJECTIVE: To describe the individual characteristics, clinical features, and morbidity associated with syncope following immunization. DESIGN: Large case series. SETTING: United States, 1990 through 1995. SUBJECTS: Reports to the national Vaccine Adverse Event Reporting System (VAERS), a passive surveillance system. An additional 3 reports of head injury (documented by medical records) were obtained through the National Vaccine Injury Compensation Program. MAIN OUTCOME MEASURES: Syncope, syncope and hospitalization, or syncope and head injury within 12 hours of vaccination. RESULTS: A total of 697 cases of syncope after vaccination was reported. Age younger than 20 years was reported for 77.4%; 57.5% were female. Hospitalization was reported in 9.6%. Of the 571 syncope events with known time, 511 occurred 1 hour or less after vaccination. Of these, 323 (63.2%) occurred 5 minutes or less, 454 (88.8%) occurred 15 minutes or less, and 500 (97.8%) occurred 30 minutes or less after vaccination. Tonic or clonic movements, which have been associated with the anoxia of vasovagal syncope, were reported in 30.4% of syncopal episodes occurring 15 minutes or less after and in 12.8% of those occurring 15 minutes or longer after vaccination (P < .001). Six patients suffered skull fracture, cerebral bleeding, or cerebral contusion after falls; 3 of these patients required neurosurgery. Falls occurred 15 minutes or less after vaccination, in or near the clinic or office. Ages ranged from 12 to 28 years; 5 of 6 were male. Follow-up revealed substantial residual impairment in 2 patients. CONCLUSIONS: Prevention of injury from syncope after vaccination and of syncope itself may be possible in many cases. Vaccinators should be aware that patients exhibiting presyncopal signs and symptoms around the time of immunization need to be evaluated carefully and may need to be assisted to sit or lie down after immunization until free of symptoms.

Accidental Falls↗
PubMed1997

Descriptive epidemiology of adverse events after immunization: reports to the Vaccine Adverse Event Reporting System (VAERS), 1991-1994.

OBJECTIVE: To provide an overview of the data, function, and performance of the Vaccine Adverse Event Reporting System. DESIGN: Descriptive and correlational analyses. SETTING: United States, 1991 through 1994. SUBJECTS: Reports to the Vaccine Adverse Event Reporting System, a passive national surveillance system, that represents temporal (but not necessarily causal) relationships between vaccinations and adverse events. MAIN OUTCOME MEASURES: Demographic variables, birth weight, vaccine type, severity of adverse event after immunization. RESULTS: A total of 38,787 adverse events was reported during the study period without a clearly increasing or decreasing trend in the annual number of total reports or deaths. Of the deaths with known age, 72.4% were reported in the first year of life, and 63.7% of these were male. The peak age for death reports was 1 to 3 months, with a gradual decline through age 9 months, after which death was relatively rare. Adverse events with onset of symptoms the day of vaccination accounted for 45.5% of total reports; 20.4% had onset of symptoms the following day. Onset within 2 weeks after vaccination was noted for 92.5% of all reports. Simultaneous administration of multiple vaccines was noted in 75.7% of reports for immunizations at ages younger than 20 years. In contrast, among those 20 years or older, only 6.0% of reports named multiple vaccines. Wide geographic variations were noted in adverse event reporting rates for children younger than 2 years, and the states with the lowest reporting rates of less serious events included the most populous states. CONCLUSIONS: The peak age of deaths at ages 1 to 3 months could be expected on the basis of prior studies showing that sudden infant death syndrome deaths peak at that age, that most deaths in the Vaccine Adverse Event Reporting System are attributed to sudden infant death syndrome, and that sudden infant death syndrome has not been associated with vaccination. The large number of reports and national coverage of the Vaccine Adverse Events Reporting System make it useful for monitoring the safety of vaccine lots and for accumulating case series to detect or better understand adverse events that may occur too rarely to be assessed in clinical trials or in the larger studies that are sometimes carried out by manufacturers after vaccine licensure (phase IV studies).

Adolescent↗
PubMed1997

Informed consent: protection or obstacle? Some emerging issues.

There is widespread consensus on the need for informed consent procedures in medical research. Nevertheless, aspects of the informed consent process remain controversial, and innovative approaches to research may raise new issues and concerns. The randomized consent design for clinical trials, proposed by Zelen (N Engl J Med 1979; 300:1242-1245), permitted physicians to randomize patients without consent, then obtain informed consent from only those patients randomized to the experimental (as opposed to the standard treatment) arm. More recently, the proposal has been made to allow waiver of informed consent for study of patients in emergency circumstances who may be temporarily incapable of providing such consent, and for whom no family member is immediately available to give a "proxy" consent (Biros M.H. et al. JAMA 1995; 273:1283-1287). The medical community and federal regulatory policy have responded differently to these proposals.

Emergency Treatment↗
PubMed1995

The data and safety monitoring board and acquired immune deficiency syndrome (AIDS) clinical trials.

The urgency of the Acquired immune deficiency syndrome (AIDS) epidemic has mandated that multiple therapeutic approaches be developed and that these approaches be evaluated through clinical trials. To oversee these trials, the National Institute of Allergy and Infectious Diseases (NIAID) has created three large clinical trial programs monitored by a Data and Safety Monitoring Board (DSMB). For each clinical trial, this Board uses a standardized approach employing contemporary biostatistical, medical, and ethical principles. The DSMB is responsible for reviewing interim data on clinical trial performance, treatment safety and efficacy, and overall study progress. If interim results provide convincing evidence of either excessive adverse effects or significant treatment benefit, the DSMB may recommend early termination of the trial to the NIAID and the study investigators. The responsibility, organization, and operating procedures of this DSMB are presented and illustrated through three clinical trials sponsored by NIAID and monitored by the Board. The rationale and operational model for the DSMB may be a useful example for the development of similar review processes in other HIV clinical trial settings.

Advisory Committees↗
PubMed1993

The use of external monitoring committees in clinical trials of the National Institute of Allergy and Infectious Diseases.

Randomized clinical trials are being conducted and/or sponsored by all scientific divisions of the National Institute of Allergy and Infectious Diseases (NIAID). External committees to review the progress of ongoing trials and to make recommendations to the Institute concerning continuation or termination are an integral part of many of these trials. These committees have evolved considerably from the ad hoc committees, called together when a need arose, which were used beginning in the mid 1970s. Currently, there are many monitoring committees operating for NIAID-sponsored trials. They function in a variety of ways, based partially on historical precedent and partially on the specialized requirements of the particular trial; there is no 'standard operating procedure' for the Institute, or even for divisions within the Institute. One of the major issues faced in establishing the data and safety monitoring board for AIDS treatment trials was access to the meetings of this board and to the reports of interim data that the board reviewed. After much discussion, procedures were established that restrict such access to a very limited group of programme and statistical centre staff. These procedures, while remaining controversial, appear necessary to ensure confidentiality and the integrity of the clinical trials process.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Do large, simple trials have a place in the evaluation of AIDS therapies?

Would trials enrolling large numbers of patients and that would require the collection of a relatively small amount of baseline and follow-up data be useful in evaluating treatments for AIDS? It seems worth considering whether widely available large, simple trials, especially those focused on optimizing dosage regimens of existing drugs, could serve the dual purpose of answering important patient management questions and improving the access of indigent populations to marketed therapies.

Acquired Immunodeficiency Syndrome↗
PubMed1990

Adjuvant therapy in stage I and stage II epithelial ovarian cancer. Results of two prospective randomized trials.

About a third of patients with ovarian cancer present with localized disease; despite surgical resection, up to half the tumors recur. Since it has not been established whether adjuvant treatment can benefit such patients, we conducted two prospective, randomized national cooperative trials of adjuvant therapy in patients with localized ovarian carcinoma (International Federation of Gynecology and Obstetrics Stages Ia to IIc). All patients underwent surgical resection plus comprehensive staging and, 18 months later, surgical re-exploration. In the first trial, 81 patients with well-differentiated or moderately well differentiated cancers confined to the ovaries (Stages Iai and Ibi) were assigned to receive either no chemotherapy or melphalan (0.2 mg per kilogram of body weight per day for five days, repeated every four to six weeks for up to 12 cycles). After a median follow-up of more than six years, there were no significant differences between the patients given no chemotherapy and those treated with melphalan with respect to either five-year disease-free survival (91 vs. 98 percent; P = 0.41) or overall survival (94 vs. 98 percent; P = 0.43). In the second trial, 141 patients with poorly differentiated Stage I tumors or with cancer outside the ovaries but limited to the pelvis (Stage II) were randomly assigned to treatment with either melphalan (in the same regimen as above) or a single intraperitoneal dose of 32P (15 mCi) at the time of surgery. In this trial (median follow-up, greater than 6 years) the outcomes for the two treatment groups were similar with respect to five-year disease-free survival (80 percent in both groups) and overall survival (81 percent with melphalan vs. 78 percent with 32P; P = 0.48). We conclude that in patients with localized ovarian cancer, comprehensive staging at the time of surgical resection can serve to identify those patients (as defined by the first trial) who can be followed without adjuvant chemotherapy. The remaining patients with localized ovarian cancer should receive adjuvant therapy, and with adjuvant melphalan or intraperitoneal 32P should have a five-year disease-free survival of about 80 percent.

Adult↗
PubMed1990

Issues in the design of drug trials for AIDS.

Although the fundamental principles that drive the design, conduct, and analysis of clinical trials are as applicable to AIDS as to other diseases, there is no question that we have been confronted with unusually difficult challenges in studying therapeutic approaches in this disease area. Treatments are being developed that show great promise, but when investigated further some may be seen to offer no clinical benefit and others may do active harm through toxicity. A group of biostatisticians, meeting in association with the AIDS Clinical Trials Group (ACTG), has discussed and written a report on a number of issues, primarily related to principles of study design, with the goal of stimulating thought on new study designs and the timely implementation of well-designed trials to identify effective treatment strategies for HIV-infected populations. These issues include (1) progression of clinical trials through phases, (2) choices of outcomes, (3) breadth and complexity of clinical trials (eligibility criteria and "low-tech" trials, (4) alternative designs to be used in randomized trials, and (5) the concept of randomized clinical trials as a desirable option, both for patients and for science. The current HIV epidemic makes the requirements of obtaining valid scientific comparisons more important, not less so, but the challenge is to expedite this process.

Acquired Immunodeficiency Syndrome↗