[Critical value of bilirubin in the selection of healthy volunteers in for phase I]. / Valeur seuil de la bilirubine pour la sélection des voloñtaires sains en phase I.

10% of young male healthy volunteers have a total bilirubin value over 20 mumol/l; thus such a value appears not relevant as screening cut off point in clinical pharmacology. This study was intended to confirm if a 27 mumol/l cut off point previously defined by the authors does not support a risk. This study dealt with 487 subjects who had together measurements of total bilirubin value and lab. tests of liver cytolysis, cholestasis or hemolysis during the selection process. 48 subjects (9.8%) had a total bilirubin value over 20 mumol/l. Correlation tests do not provide arguments of cytolysis, cholestasis or hemolysis and there was no argument in favor of Gilbert's syndrome. Out of 48 hyperbilirubinemic subjects only 22 were included in clinical pharmacology studies. In more than 60%, the total bilirubin value returned to normal spontaneously and in no case appeared a significant clinical, biological, pharmacokinetic or dynamic abnormality. Except a possible increase of slow acetylor frequency, the medical literature analysis does not show any relevant modification in metabolism, pharmacokinetics or pharmacodynamics until a 40 mumol/l value of total bilirubin. Thus, the 27 mumol/l value of total bilirubin previously proposed is confirmed as a useful limit that does not lead to an additional risk.

Upper limit of plasma alanine amino transferase during phase I studies.

In Phase I clinical studies, the maximum tolerated dose has to be determined by a case by case analysis sometimes using a laboratory adverse effect, e.g. an increase in alanine amino transferase (ALT). For this reason a threshold to discriminate between significant or non significant adverse changes in ALT is required particularly in Phase I studies, in order to deal with the very common "close to the limit values". Previous methods (limit of normal range or normal range plus an arbitrary margin) do not solve this problem. The authors propose a new method taking into account the threshold used as inclusion criteria for ALT (R) and the range of spontaneous variations measured under identical Phase I study conditions (V). The (R) and (V) thresholds, respectively, are defined as 50 IU.l-1 and a 50% increase, from baseline. Thus an ALT value is recognized as a "significant adverse experience" if it exceeds 50 IU.l-1 above an increase from baseline exceeding 50% of the baseline value. To highlight the value of the method, it was implemented in a one year period including 8 studies and 134 subjects. The sensitivity, specificity and positive predictive value of various methods were compared. The results showed the following: Six out of 134 subjects had significant adverse changes in ALT (4%); and all these 6 subjects were detected by the proposed new method without error. Eight subjects including two false positives, were detected by an use of the normal range limit, and only 4 were detected using, the 10% margin.(ABSTRACT TRUNCATED AT 250 WORDS)

Adverse events in phase one studies: a study in 430 healthy volunteers.

All the clinical, laboratory and electrocardiographic adverse events detected during 24 Phase I studies in the same unit over a 5 y period are reported here. 430 healthy male volunteers were involved, corresponding to 5488 days of follow-up. The overall incidence of adverse events was 13.5%, with a significant difference between active drug (15.3%) and placebo (7.4%) treatments. There were 69 distinct types of adverse events. Headache was the most frequent symptom (2%). There were severe adverse events in 20 cases (0.36%), with an incidence of 20/430 per subject (4.6%). There were no deaths or life-threatening events. Although the main objective of Phase I studies is to determine the maximum dose tolerated, cause-effect relationships with adverse events are hard to establish, because of the frequency of adverse events with placebo, and because of the limited number of subjects included such studies.

Adverse events in phase-I studies: a report in 1015 healthy volunteers.

OBJECTIVE: This report describes all clinical, laboratory and electrocardiographical adverse events detected in healthy volunteers in a phase-I centre over a 10-year period: 54 phase-I studies are involved, including 1015 healthy young volunteers (993 males) who received 1538 treatments (23 different active drugs or placebo) corresponding to 12143 days of follow-up. This updates a similar report published previously in the European Journal of Clinical Pharmacology. METHODS: Adverse events were defined as all events noted in case-report forms. Incidence of adverse events was defined as the ratio between the number of adverse events and the number of follow-up days. Severity was rated as death, life-threatening, severe or minor. Incidences or occurrence rates were compared using the Chi-squared test with Yates' correction. RESULTS: The overall incidence of adverse events was 12.8% with a significant difference between active-drug (13.7%) and placebo (7.9%) treatments. There were 1558 adverse events of 110 distinct kinds. Only for three (headache, diarrhoea and dyspepsia) was the incidence superior to 10 per thousand. Most of these adverse events were also observed with placebo. Ninety-seven percentage of adverse events were of minor intensity; forty three (3%) were rated as severe, including nine worrying cases - six malaises with loss of consciousness, one atrial fibrillation, one hyperthyroidism and one bicytopenia. Some of the adverse events were not related to the tested drugs, but to a vagal reaction or to study conditions. There was no death or life-threatening event. The global rate of occurrence was one adverse event per treatment, one and a half per subject and one out of eight follow-up days. No difference in the overall incidence with placebo was observed between the two successive 5-year periods. CONCLUSIONS: This report confirms that adverse events in phase I studies are very common, usually of minor intensity and rarely severe; even though exceptional, life-threatening adverse events are possible. Adverse events occurring in phase I are rarely published, leading to lack of information. Thus, authors invite clinical research organization (CROs) and phase-I centres to regularly publicise at least severe adverse events; they also suggest that the life-threatening adverse events reported to health authorities should be publicised, for example by the World Health Organization (WHO).

Laboratory data in healthy volunteers: reference values, reference changes, screening and laboratory adverse event limits in Phase I clinical trials.

OBJECTIVE: Laboratory data are key evaluation procedures for Phase I clinical pharmacology for two reasons. Firstly, laboratory data are used within the screening process to exclude subjects with asymptomatic diseases, which could result in increased danger to themselves or confuse interpretation of the study results. Secondly, during study implementation, safety evaluation and in particular maximum tolerated dose determination have to be done by a case-by-case analysis, sometimes using laboratory adverse events (LAEs). Thus, relevant limits are needed to discriminate between a usual common variation and a significant abnormality, which is considered to be a LAE. This report presents laboratory data distribution, reference values and reference changes and, based on previously published new methods, suggests inclusion limits at screening and laboratory adverse event limits for analysis during study implementation. SUBJECTS AND METHODS: Nine hundred and twenty-seven young healthy male volunteers were recruited in one centre (Association de Recherche Thérapeutique). A standard screening process was carried out. Protocols were approved by the local ethics committee. Blood sampling was performed in the same conditions. Reference values (at screening and at baseline) were determined by a non-parametric procedure selecting 2.5% and 97.5% of the distribution of data. Reference changes were also defined as the 2.5-97.5% interval of distribution of the variations between the end of treatment and baseline. Inclusion limit and LAE limit methods of determination used had been specified in previous articles. RESULTS: Detailed results of laboratory data distribution, reference values at screening and at baseline, reference changes, inclusion limits and LAE limits are presented in tables with number of subjects, mean, median, standard deviation, minimal and maximal values and the 2.5-97.5% interval for each laboratory parameter. CONCLUSION: The key aims of this paper are to provide clinical pharmacologists with data, reference values or changes obtained in the real conditions of Phase I study implementation, and to propose relevant limits, either for screening as inclusion limits, or during studies as LAE limits. Thus, these data, reference values and specific limits improve the capacity to screen healthy volunteers and to analyse LAEs during Phase I studies.