Serial Monitoring and Hyperimmunoglobulin versus Standard of Care to Prevent Congenital Cytomegalovirus Infection: A Phase III Randomized Trial.

INTRODUCTION: Nonrandomized studies support the potential of cytomegalovirus hyperimmunoglobulin (CMV-HyperIg) in preventing maternofetal CMV transmission, but prospective interventional studies show equivocal results. We pre-sent a prospective phase-III international randomized open-label trial on the potential effect of CMV-HyperIg following serial monitoring of CMV serostatus. METHODS: CMV-seronegative pregnant women (gestational age [GA] <14 weeks) were 1:1 randomized to monthly CMV-serostatus monitoring and CMV-HyperIg upon seroconversion (treatment), or routine prenatal care with CMV-serostatus testing at end of pregnancy (control). Ethical considerations required that control subjects with confirmed seroconversion be offered Cytotect®. The primary endpoint was the proportion of fetuses/newborns with congenital CMV infection. Secondary endpoints included neonatal CMV disease and safety during the 24-month follow-up. RESULTS: The treatment arm counted 4,800 randomized subjects: 52 seroconverted (median GA 24 [11-35] weeks), of which 45 completed follow-up. The control arm counted 4,735 randomized subjects: 42 seroconverted, of which 34 completed follow-up (evaluable data for 28 newborns) and 8 subjects chose off-label Cytotect®. Congenital CMV rates were 13/28 newborns (46.4% [CI 27.51; 66.13]) vs. 16/45 newborns (35.6% [CI 21.87; 51.22]) in control and treated arms, respectively (p = 0.46). Newborn CMV disease was mostly mild and spontaneously resolving. There were no major safety concerns. The target sample was not reached within an acceptable time frame. CONCLUSIONS: Serial monitoring of CMV serostatus with CMV-HyperIg treatment was associated with a mild nonsignificant reduction in the vertical CMV transmission rate. Studies on the optimal preventive strategy are hampered by epidemiological and ethical challenges and should focus on GA-dependent transmission rates and accurate dating of infection.

Quality assurance in non-interventional studies.

Nowadays, drug research and surveillance after authorisation becomes more and more important for several reasons. Non-interventional studies (NIS) investigate various aspects of drug use including efficacy and safety under real life conditions. Such kind of health services research should be on a high scientific, methodological and organisational level. Therefore accompanying measures to improve or to keep the quality are highly recommended. The aim of quality management is: first to avoid bias of results by using an appropriate study design and an adequate data analysis, second to assure authenticity, completeness and validity of the data and third to identify and resolve deficiencies at an early stage. Basic principles are laid down in corresponding guidelines and recommendations of authorities, institutes and societies. Various guidelines for good epidemiological practice (GEP) were published by the U.S. Food and Drug Administration (FDA) and international and regional societies for epidemiology. In addition in Germany the Federal Institute for Drugs and Medical Devices (BfArM) together with the Paul Ehrlich Institute (PEI) and the German Association of Research-Based Pharmaceutical Companies (VFA) have published respectively recommendations dealing with quality aspects of non-interventional observational studies. Key points are the advanced publishing of information about the project, developing of a study plan/protocol containing the scientific objectives, a sample size justification and a description of the planned analyses and the publishing of a summary of the results timely after completion of the study. The quality of the data can be improved by using standardized case report forms (CRF) and the CRF should be reviewed and tested before start of study by some participants. A source data verification (SDV) should be performed in randomly selected centres - in between 2% and 5% of the centres depending on the number of participating centres. Before start of statistical analysis a statistical analysis plan (SAP) should be created. The use of standardized tables and figures is highly recommended. The basis of the report writing should be the STROBE-statement "Strengthening the Reporting of Observational studies in Epidemiology Initiative" containing a checklist of 22 points to be covered in the report. The development of own standard operating procedures (SOP) describing the processes during planning, conduct and evaluation of a non-interventional study as well as the quality management and the regular training of all involved people is also highly recommended. All accompanying measures to improve or to keep the quality of the NIS should not violate the concept of non-intervention.