Alzheimer Disease: Gordon B

Doody RS, Geldmacher DS, Gordon B, Perdomo CA, Pratt RD, Anonymous00078. · Department of Neurology, Baylor College of Medicine, 6550 Fannin Street, Suite 1801, Houston, TX 77030-3498, USA. · Arch Neurol. · Pubmed #11255446 links to  free full text

Abstract: BACKGROUND: Donepezil hydrochloride is a selective acetylcholinesterase inhibitor approved for the symptomatic treatment of mild to moderately severe Alzheimer disease (AD). Controlled clinical trials of up to 24 weeks have demonstrated that donepezil treatment (5 and 10 mg/d) significantly improves cognition and global function. OBJECTIVE: To investigate the long-term benefits of donepezil treatment in patients with AD. DESIGN: Multicenter, open-label, 144-week extension of 2 US phase 3, double-blind, placebo-controlled clinical trials: a 15-week study (12 weeks of treatment followed by a 3-week placebo washout) and a 30-week study (24 weeks of treatment followed by a 6-week placebo washout). INTERVENTIONS: All patients (N = 763) initially received donepezil, 5 mg/d, for 6 weeks, after which an increase to 10 mg/d was encouraged. MEASURES: Primary efficacy measures were the Alzheimer's Disease Assessment Scale-cognitive subscale and the Clinical Dementia Rating-Sum of the Boxes. RESULTS: After the shorter 3-week placebo washout, donepezil-associated benefits remained above original baseline values for an additional 24 weeks of open-label treatment. Benefits on Alzheimer's Disease Assessment Scale-cognitive subscale scores for patients who received 10 mg/d in the double-blind study were evident compared with the other groups for 108 weeks of open-label treatment. In contrast, donepezil-associated benefits were lost after the 6-week placebo washout, and scores decreased below original baseline values for all patient groups. Although scores improved relative to the new open-label study baseline scores after drug use was restarted, patients remained below original baseline values. The most common adverse events were associated with the nervous and digestive systems and were generally mild and transient; 17% of patient discontinuations were associated with adverse events. CONCLUSIONS: Donepezil is an effective and safe drug for the long-term symptomatic treatment of mild to moderately severe AD for up to 144 weeks (2.8 years), and sustained treatment may confer some advantages.

Chang WP, Koelsch G, Wong S, Downs D, Da H, Weerasena V, Gordon B, Devasamudram T, Bilcer G, Ghosh AK, Tang J. · Protein Studies Program, Oklahoma Medical Research Foundation, 825 NE 13th Street, Oklahoma City, OK 73104, USA. · J Neurochem. · Pubmed #15189343 No free full text.

Abstract: We have previously reported structure-based design of memapsin 2 (beta-secretase) inhibitors with high potency. Here we show that two such inhibitors covalently linked to a "carrier peptide" penetrated the plasma membrane in cultured cells and inhibited the production of beta-amyloid (Abeta). Intraperitoneal injection of the conjugated inhibitors in transgenic Alzheimer's mice (Tg2576) resulted in a significant decrease of Abeta level in the plasma and brain. These observations verified that memapsin 2 is a therapeutic target for Abeta reduction and also establish that transgenic mice are suitable in vivo models for the study of memapsin 2 inhibition.