Laboratory safety data, clinical trials

Laboratory safety data When the CRFs arrive at the data manager s office, questions will arise relating to laboratory safety data. Queries may occur at the investigator site and advice can be requested from the pharmaceutical physician associated with the clinical trial in the sponsor company. 

Drug Levels in Plasma. Drug levels may also be measured in a clinical trial. Such levels are usually part of a pharmacokinetic analysis but also provide important safety data. This information would be particularly relevant in cases of suspected or actual drug overdosage, drug interactions, to correlate medicine levels with toxic events, or in other situations. It must be clarified whether free levels of the drug and/or the protein bound will be measured by the laboratory. 

The conduct of toxicology studies in laboratory animals has been driven by experience, historical precedence, and governmental requirements, and the results of these studies usually, and reasonably, have led to restrictions on the use, or method of use, of the chemicals concerned [1], The primary objective of pharmaceutical preclinical safety evaluation is to provide information essential for the initiation of clinical trials. Scientific rationale and controlled reproducible data are used to show that the initial human risk is so low as to be ethically and practically acceptable in relation to the medical value of the information to be obtained from humans. Preclinical safety studies performed throughout the course of product development facilitate and may guide work... 

It is common practice to employ outside laboratories to perform testing for safety and efficacy measures in clinical trials. Along with the results, these laboratories will also provide the units and normal ranges for the tests performed. Since the laboratories are typically utilized by many patients in a study or even across studies, it is practical for the units and ranges to be received and entered once in the system and then linked internally to the patient data to which they apply. This principle of centrally storing values that can be shared across the system is also desirable for maintaining the conversion factors used in deriving lab results into standardized units. 

Data may be organized by type of data, such as adverse events, laboratory data, demography, physical exam, etc. Since many of these categories of data exist across clinical trials, standard file structures can be designed and implemented. This standardization allows for the reuse of validated software as well as facilitates the pooling of data across studies for use in project safety summaries and other data reporting across studies. 

The safety of continuous itraconazole (50-200 mg/day for up to 3 months) in the treatment of onychomycosis and dermatomycosis has been reviewed, using pnblished and unpublished data from clinical trials (15). The overall incidence of adverse events in patients who took continuous itraconazole (21%) differed little from that in patients who took either topical miconazole or oral placebo (18%). The most frequently reported adverse events were gastrointestinal disorders (6.7%), headache (4.2%), and skin disorders (2.7%). No data were given on the incidence of serious adverse events attributed to itraconazole. Among laboratory abnormalities, clinically significant rises in liver function tests occurred in 3.4% of 527 patients treated with itraconazole (2.6% in patients treated with 50-200 mg/day for dermatomycosis versus 6.6% in patients treated with 200 mg/day for 3 months for onychomycosis). 

Safety monitoring in clinical studies can be both data and labor intensive. In the context of later-stage therapeutic exploratory and therapeutic confirmatory trials, the collection of laboratory data is no exception. Typically, participants in clinical trials provide blood or urine samples at every clinic visit. There is an expansive range of clinical chemistry tests that can be conducted using these samples. 

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