Parallel-group studies

Parallel group studies are not particularly useful for IVIVC development, as by definition, subjects receive only one treatment and so there would be no reference for each subject for individual deconvolution. This becomes less problematic as the variability of the drug declines. Thus, it may be acceptable for a low variability drug to use a mean reference profile for deconvolution of the mean profile for each ER treatment. 

Bousquet, J, Tosserard, B., and Medley, H.V., Double-blind parallel group study to compare the long term clinical efficacy and safety of two different methods of administering inhaled fluticasone propionate in chronic severe asthmatic patients, Eur. Resp. J., 8 427S (1995). 

Johnson JR, Bumell-Nugent M, Lossignol D, Ganae-Motan ED, Potts R, Fallon MT. (2010) Multicenter, double-blind, randomized, placebo-controlled, parallel-group study of the efficacy, safety, and tolerability of THC CBD extract and THC extract in patients with intractable can correlated pain. J Pain Symptom Manage 39 167-179. 

Biederman J, Krishnan S, Zhang Y, McGough JJ, Findling RL. (2007) Efficacy and tolerability of lisdexamfetamine dimesylate (NRP-104) in children with attention-deficit/hyperactivity disorder A Phase 111, multicenter, randomized, double-blind, forced-dose, parallel-group study. Clin Ther 29 450 63. 

Gadow et al. (1995), however, found no increase in tics in a placebo-controlled trial of methylphenidate in children with ADHD and a tic disorder. Other trials of stimulants in such children have found little or no average increase in tic severity scores, but clinically significant increases of tics in a handful of subjects severe enough to prompt discontinuation of the stimulant (Castellanos et al., 1997 Law and Schachar, 1999) or to require addition of a medication to control their tic symptoms (Gadow et al., 1999). A multicenter, doubleblind, placebo-controlled, parallel group study of methylphenidate and clonidine, used alone or in combination in 136 children with ADHD and a comorbid... 

Bruggeman, R., van der Linden, C., Buitelaar, J.K., Gericke, G.S., Hawkridge, S.M., and Temlett, J.A. (2001) Risperidone versus pimozide in Tourette s disorder a comparative double-blind parallel-group study. / Clin Psychiatry 62 50—56. 

The efficacy and tolerability of paroxetine was examined in a multinational, double-blind, placebo-controlled, parallel-group study with 399 patients with OCD (Zohar et al. 1994). Two hundred one patients received paroxetine (mean dose = 37.5 mg), 99 received CMI (mean dose = 113.1 mg), and 99 received placebo. Paroxetine was of comparable efficacy to CMI, and both were significantly more effective than was placebo. 

Biederman I, Lopez FA, Boellner SW, et al A randomized, double-blind, placebo-controlled, parallel-group study of SLI381 (Adderall XR) in children with attention-deficit/hyperactivity disorder. Pediatrics 110 258-266, 2002... 

In a double-blind, parallel-group study, Bondareff et id. (2000) compared the SSRI sertraline and the tricyclic compound nortriptyline with regard to their efficacy and safety in a group of 210 outpatients 60 years and older. The patients met the DSM-DI-R criteria for major depressive episode and had a minimum score of 18 on the Hamilton Rating Scale for Depression. Their mean age was about 68 years, most patients were white and about 60% were female the severity of depression was rated as moderate in more than 70% and as severe in more than 20% of the cases. The daily doses of sertraline were between 50 and 150 mg, and those of nortriptyline were 25 100 mg the treatment lasted 12 weeks. In addition to clinical rating scales and self-assessment instruments, patients took the following tests of cognitive performance ... 

Cassano, G.B., Jori, M.C., on behalf of the AMIMAJOR investigators Efficacy and safety of amisulpride 50mg versus paroxetine 20 mg in major depression a randomized, double-blind, parallel group study, bit. Clin. Psvchopharmacol. 17, 27-32, 2002. 

Zander M, Madsbad S, Madsen JL, Holst JJ. Effect of 6-week course of glucagon-like peptide 1 on glycaemic control, insulin sensitivity, and beta-cell function in type 2 diabetes a parallel-group study. Lancet 2002 359(9309) 824-30. 

In a randomized, parallel-group study, there were fewer episodes of nocturnal and serious hypoglycemia when insulin glargine was compared with once- or twice-daily protamine zinc insulin (13,14). Other adverse reactions and reactions at the injection sites were identical. 

Insulin aspart, insulin lispro, and buffered regular insulin in continuous subcutaneous insulin infusion have been compared in an open, randomized, parallel-group study in 146 patients (24). HbAlc, hypoglycemic episodes, and blockages of pumps or infusion sets did not differ. 

Intravenous conivaptan had no effects on the electrocardiogram in a randomized, single-blind, placebo- and positive-controlled, parallel-group study, in which an intravenous loading dose of conivaptan of 20 mg was followed by a continuous infusion of 40 or 80 mg/day for 4 days or moxifloxacin 400 mg/day for 4 days (9). 

There are two forms of the f-test, and each is applicable for sets of measurements that have been obtained in different ways. The method of data collection precisely and uniquely determines which of these two forms of statistical analysis is appropriate. Section 7.6 introduced the independent groups Mest, which is appropriate for the analysis of data collected during a study employing a parallel group study design. Another form of the Mest is called the dependent measures t-test. This test is sometimes called the related measures Mest, the repeated measures Mest, or the Mest for matched pairs. The name dependent measures Mest has been chosen here since the contrast with the word independent in the name independent groups Mest is clear. 

Barnett,A.H.,Dreyer,M.,Lange,P., and Serdarevic-Pehar, M. (2006), An open,randomized, parallel-group study to compare the efficacy and safety profile of inhaled human insulin (exubera) with glibenclamide as adjunctive therapy in patients with type 2 diabetes poorly controlled on metformin, Diabetes Care, 29,1818-1825. 

Eriksen, B. (1999), A randomized, open, parallel-group study on the preventive effect of an estradiol-releasing vaginal ring (Estring) on recurrent urinary tract infections in postmenopausal women, Am. J. Obstet. Gynecol., 180,1072-1079. 

In a placebo-controlled, parallel-group study of buspir-one and amantadine in 57 patients with fluoxetine-induced sexual dysfunction, there was an overall improvement in all three treatment groups and no significant differences between them (68). These data suggest that anecdotal reports of treatment benefit in SSRI-induced sexual dysfunction should be regarded with caution. 

Peuskens J. Risperidone in the treatment of patients with chronic schizophrenia a multi-national, multi-centre, doubleblind, parallel-group study versus haloperidol. Risperidone Study Group. Br J Psychiatry 1995 166(6) 712-26. 

Ziprasidone is apparently well tolerated, with a limited potential to cause extrapyramidal adverse effects or weight gain (4). Out-patients who partly respond to conventional antipsychotic drugs, risperidone, or olanzapine may have improved control of psychotic symptoms after switching to ziprasidone, according to the results of a reanalysis of 6-week, multicenter, randomized, open, parallel-group studies in patients with schizophrenia who had previously taken conventional antipsychotic drugs (n = 108), olanzapine (n = 104), or risperidone (n = 58) these results have been published in two different journals (5, 6). 

The psychomotor and amnesic effects of single oral doses of lorazepam 2 mg were studied in 48 healthy subjects in a double-blind, placebo-controlled, randomized, parallel-group study (9). The effects were assessed by a battery of subjective and objective tests that explored mood and vigilance, attention, psychomotor performance, and memory. Vigilance, psychomotor performance, and free recall were significantly impaired by lorazepam. 

The safety and tolerability of once-daily oral metrifonate has been evaluated in patients with probable mild to moderate Alzheimer s disease in a randomized, doubleblind, placebo-controlled, parallel-group study (9). Metrifonate was given to 29 patients as a loading dose (2.5 mg/kg) for 2 weeks, followed by maintenance dose (1 mg/kg) for 4 weeks 10 patients received placebo. The proportion of patients who had at least one adverse event was comparable in the two groups metrifonate 76%, placebo 80%. Selected adverse events, defined as those for which the incidence in the metrifonate and placebo group differed by at least 10%, were diarrhea, nausea, leg cramps, and accidental injury. The adverse events were predominantly mild and transient. Those who took metrifonate had a significantly lower heart rate. Metrifonate had no clinically important effect on laboratory tests, such as liver function tests, and did not affect exercise tolerance or pulmonary function. 

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