Placebo studies

Phase II investigates the compound s efficacy and safety in controlled clinical trials for a specific therapeutic indication. To eliminate as many competing factors as possible, Phase II trials are narrowly controlled. They are characterized as small—several hundred subjects with the indicated disease or symptoms—and are closely monitored. The control may be either a placebo study arm or an active control arm. The endpoint measured may be the clinical outcome of interest or a surrogate. Phase II trials may last for several months or even several years. Early pilot trials to evaluate safety and efficacy are called Phase Ila. Later trials, called Phase lib, are important tests of the compound s efficacy. These trials may constitute the pivotal trials used to establish the drug s safety and efficacy. At least one pivotal trial (most frequently a large, randomized Phase III study) is done. Only about one third of compounds entered into Phase II will begin Phase III studies [61],... 

Meyer B. (1986a). [Multicenter randomized double-blind drug vs. placebo study of the treatment of tinnitus with Ginkgo biloba extract]. Presse Med. 15(31) 1562-64. 

Horak F Immunotherapy with sublingual birch pollen extract. A short-term double blind placebo study. J Investig Allergol Clin Immunol 1998 8/3 165—171. 

Coble PA, Kupfer DJ, Spiker DG, Neil JF, McPartland RJ (1979) EEG sleep in primary depression a longitudinal placebo study. J Affect Disord 1 131-138... 

Zaleplon and triazolam have been compared in two concurrent multicenter, randomized, double-blind, placebo-controlled crossover studies in chronic insomniacs (12). Study 1 compared zaleplon (10 and 40 mg) with triazolam (0.25 mg) and placebo study 2 compared zaleplon (20 and 60 mg) with triazolam (0.25 mg) and placebo. All doses of zaleplon produced significant reductions in... 

The VEGF trap was later evaluated as an intravitreal injection in a phase I trial, structured without a placebo study arm. Three patients at each of 4 dose levels (0.05-, 0.15-, 0.5-, and 1.0-mg) have received the study medication. Preliminary results note that excess foveal thickness was reduced by at least 70% in 75% of patients, and acuity was stable or improved in 75% of subjects. Although this drug is in preliminary clinical trials, it offers an approach to VEGF inhibition that is different from aptamer or monoclonal antibody strategies. 

Cadranel, J.F., El Younsi, M., Pidoux, B., Zylberberg, P., Benhamou, Y., Valla, D., Opolon, P. Flumazenil therapy for hepatic encephalopathy in cirrhotic patients a double-blind pragmatic randomized, placebo study. Eur. X. Gastroenterol. Hepatol. 1995 7 325-329... 

Duarte C, Baehre M, Gharakhanian S, Leynadier F French Azelastine Study Group. Treatment of severe seasonal rhinoconjunctivitis by a combination of azelastine nasal spray and eye drops a double-bhnd, double-placebo study. J Investig Allergol Chn Immunol 2001 11(1) 34-40. 

Caplan RA, Ready LB, Oden RV, Matsen FA 3rd, Nessly ML, Olsson GL. Transdermal fentanyl for postoperative pain management. A double-blind placebo study. JAMA 1989 261(7) 1036-9. 

Suppose, as an example, we now apply 2 1 and 3 1 allocation to the active/placebo study considered in Section 7.4.3.3.I. Just the results for 95% power will be used (Table 7.15). 

Although these two studies suggest that donepezil may be effective in treating children and adolescents with autism, the results are not conclusive and more double-blind placebo studies need to be carried out. 

Taillandier J, Aimnar A, Rabourdin JP, Ribeyre JP, Pichon J, Niddam S, Pierart H (1986) Treatment of cerebral aging disorders with Ginkgo biloba extract. A longitudinal multicenter double-blind drug vs. placebo study. Presse Med 15(31) 1583-1587... 

Lanthony P, Cosson JP (1988) The course of color vision in early diabetic retinopathy treated with Ginkgo biloba extract. A preliminary double-blind versus placebo study. J Fr Ophtahnol ll(10) 671-674... 

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