The role of an initial single-blind placebo period in phase I clinical trials.
The effect of an initial single-blind placebo period in a phase I clinical trial was assessed in 12 volunteers who underwent five weekly treatment periods, consisting of treatment on the first day and a six-day wash-out period. An initial single-blind placebo period was followed by three different single doses of a platelet-aggregation factor inhibitor and another placebo period, under a double-blind Latin square design. Reports of abnormal symptoms were collected using a questionnaire designed by our group. A total of 13 abnormal symptoms were reported during the first period and only nine for the following four periods, indicating a clear placebo period effect. These preliminary results suggest that an initial single-blind period may be usefully included in phase I clinical trials.
Unité de Pharmacologie Clinique, Hôpital Cardiologique, Lyon, France.
P
P
Nony
J P
JP
Boissel
P
P
Girard
L
L
Lion
M C
MC
Haugh
S
S
Fareh
B
B
De Breyne
D017321:Clinical Trials, Phase I as Topic / Q000379:methods*; D004311:Double-Blind Method; D006801:Humans; D008297:Male; D015990:Placebo Effect; D010972:Platelet Activating Factor / Q000037:antagonists & inhibitors*; D010975:Platelet Aggregation Inhibitors / Q000009:adverse effects; D016037:Single-Blind Method; D011795:Surveys and Questionnaires
D010972:Platelet Activating Factor; D010975:Platelet Aggregation Inhibitors