ispronicline and Cognition-Disorders

Targacept (formerly a subsidiary of RJ Reynolds) is developing ispronicline, the lead in a series of nicotinic acetylcholine (nACh) ligands, as a potential oral treatment for cognitive impairment, including a variety of non-Alzheimer's dementias. In July 2005, Targacept was preparing for a phase II study in patients with mild-to-moderate Alzheimer's disease.

Topics: Animals; Clinical Trials as Topic; Cognition Disorders; Humans; Molecular Structure; Neuroprotective Agents; Pyridines; Receptors, Nicotinic; Structure-Activity Relationship; Treatment Outcome

Laboratory studies have found that acute stimulation of nicotinic acetylcholine receptors improves cognition in adult attention-deficit/hyperactivity disorder (ADHD). Clinical trials of nicotinic agonists have been mixed, underscoring the need to understand the mechanisms for individual differences in clinical response. Using cognitive models within a clinical trial framework may provide insight into these differences.. This was a within-subjects, randomized, placebo-controlled double-blind trial of the nicotinic agonist AZD3480 (also termed TC-1734) at doses of 5 mg and 50 mg and placebo in adults with ADHD. The order of the 2-week treatment periods was randomized, and a 3-week wash out separated each drug treatment period. Response inhibition (Stop Signal Task [SST]) and clinical efficacy (Investigator Rated Conners Adult ADHD Rating Scale [CAARS-INV]) were the a priori primary outcome measures of cognitive and clinical effects. We hypothesized that AZD3480 treatment would improve SST performance and clinical symptoms (CAARS-INV Total ADHD Symptoms Score).. Thirty subjects were randomized, with 24 included in the intent-to-treat analyses. SST performance and total ADHD symptoms were significantly improved with 50 mg of AZD3480. CAARS-INV ratings of inattention, memory problems, and emotional lability/impulsivity were significantly improved with 50 mg of AZD3480.. These results support previous work suggesting that nicotinic agonists are viable as treatments for adult ADHD. Measuring cognitive endophenotypes related to both the disorder and mechanism of treatment may help further rational drug development for dimensional features that cross-cut psychiatric disorders.

Topics: Adolescent; Adult; Aged; Attention Deficit Disorder with Hyperactivity; Cognition Disorders; Dose-Response Relationship, Drug; Double-Blind Method; Female; Humans; Male; Middle Aged; Neuropsychological Tests; Nicotinic Agonists; Psychiatric Status Rating Scales; Pyridines; Young Adult

AZD3480 is a selective agonist of α4β2 central neuronal nicotinic receptors (NNRs). This study investigated its effects on cognition, relative to placebo, in 440 patients with stable schizophrenia who were taking a single atypical antipsychotic medication and who were active cigarette smokers. Mean age was 41 (range 19 to 55) years and the majority of patients (88%) had a diagnosis of paranoid schizophrenia. Patients were randomized to one of 3 doses of AZD3480: 5 mg, 20 mg, and 35/100 mg (depending on CYP2D6 metabolic status), or to placebo. Treatment was given once daily for 12 weeks. The primary outcome measure was change in cognitive function from baseline to Week 12, as measured by IntegNeuro computerized test battery of cognitive function scores. Secondary outcome measures included assessment of functional capacity (University of California at San Diego Performance Based Skills Assessment [UPSA2]) and adaptive function (Social Functioning Scale [SFS]). AZD3480 failed to improve cognition relative to placebo in this population of patients or in subpopulations defined by disposition, metabolic status, antipsychotic treatment, age, age of illness onset, and sex. Likewise, no improvement relative to placebo was observed in either the SFS measure of adaptive functioning or the UPSA2 measure of functional capacity. AZD3480 was generally well tolerated in the population studied.

Topics: Adult; Cognition; Cognition Disorders; Female; Humans; Male; Middle Aged; Nicotinic Agonists; Pyridines; Schizophrenia

Cognitive decline is a feature of ageing and can be defined as normal (age-associated memory impairment) or pathological (mild cognitive impairment/Alzheimer's disease). Stimulation of selective brain-specific neuronal nicotinic acetylcholine receptors might offer symptomatic treatment for normal ageing. The objective of this study was to assess the safety, tolerability and efficacy of TC-1734 (AZD3480), a selective α4β2 nicotinic agonist, in the treatment of age-associated memory impairment. A randomized placebo-controlled trial was conducted in 16 community-based centers within the USA. Subjects who met objective criteria for age-associated memory impairment were recruited between November 2004 and December 2005. Subjects were randomly assigned to receive orally 25 mg (n = 59), 50 mg (n = 68) TC-1734 (AZD3480) or placebo (n = 66) in a double-blind fashion for 16 weeks. Main outcome measures included routine clinical safety measures, tolerability, cognitive assessment via the Cognitive Drug Research computerized test battery and a Subject Global Impression Scale of Cognition (SCI-Cog). Two outcomes from the computerized test battery - a factor assessing attention and one assessing episodic memory, along with the SGI-Cog were defined as co-primary outcome variables. Baseline to Week 16 differences from placebo for 50 mg TC-1734 (AZD3480) were considered of primary importance. For 50 mg TC-1734 (AZD3480) attention factor the mean drug-placebo difference was 22.9 (95% confidence interval 4.8 to 41.4) p = 0.01 for episodic memory factor the difference was -7.6 (95% confidence interval -14.4 to -0.8), p = 0.029, and for the SGI-Cog the difference was 0.99 (95% confidence interval 0.2 to 1.8), p = 0.015. As all three co-primary outcomes were positive it can be concluded the compound likely had a beneficial effect on cognition. TC-1734 (AZD3480) appeared safe and well tolerated in this study.

Topics: Administration, Oral; Aged; Aged, 80 and over; Cognition Disorders; Dose-Response Relationship, Drug; Double-Blind Method; Female; Humans; Male; Memory Disorders; Middle Aged; Pyridines; Treatment Outcome

AZD3480 is a selective agonist of the central α4β2 and α2β2 neuronal nicotinic cholinergic receptors (NNRs). Its effects on cognition were investigated in 567 patients with mild-to-moderate Alzheimer's disease (AD) (Mini Mental State Examination [MMSE] 12-26). Mean baseline MMSE was 21 (SD ± 3.7), with 61% of patients having mild disease (MMSE 21-26). Mean age was 74 (range 58-85) years. Patients were randomized to one of 5 treatment groups: AZD3480 5 mg, 20 mg or 35/100 mg, donepezil 10 mg (active comparator) or placebo, and treated once daily for 12 weeks. The primary outcome measure was change from baseline at Week 12 on the AD Assessment Scale-Cognitive Subscale (ADAS-Cog). Neither AZD3480 nor donepezil showed a statistically significant improvement versus placebo on ADAS-Cog. Improvements in a number of secondary outcome measures (MMSE, AD Cooperative Study-Clinical Global Impression of Change (ADCS-CGIC) and Disability Assessment for Dementia [DAD]) were observed for AZD3480 and for donepezil. A post-hoc analysis on ADAS-Cog, excluding patients with very mild AD (MMSE 25-26) indicated improvement versus placebo for AZD3480 20 mg (-1.4, 95% CI: -3.0; 0.2) and donepezil (-1.0, 95% CI: -2.3; 0.3). AZD3480 was well tolerated. The study did not meet proof of concept criteria: since neither AZD3480 nor donepezil were statistically significantly superior to placebo on ADAS-Cog and was considered to be inconclusive. Further studies are required to determine the therapeutic potential of stimulating α4β2 receptors with NNRs in AD patients.

Topics: Aged; Aged, 80 and over; Alzheimer Disease; Cholinesterase Inhibitors; Cognition Disorders; Donepezil; Dose-Response Relationship, Drug; Double-Blind Method; Female; Humans; Indans; Male; Mental Status Schedule; Neuroprotective Agents; Neuropsychological Tests; Piperidines; Pyridines; Time Factors; Treatment Outcome