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72/100

✓ Peer-reviewed alzhub usefulness score 72 out of 100. Treatments

Topic: Brain proteins, microglia and lab models

Plain-language summary

Aim The aim of this study was to characterize the pharmacokinetic and pharmacodynamic profile of donepezil HCl, a chemically distinct and specific acetylcholinesterase (AChE) inhibitor for the treatment of Alzheimer's disease, following administration of single oral doses. Methods This was a double-blind, randomized, single-dose, placebo-controlled, sequential-group, ascending-dose study in healthy male volunteers (n = 48). Six dose levels were investigated, ranging from 0.3 to 6.0 mg. Donepezil concentrations in plasma were determined by HPLC with UV detection. Pharmacodynamic activity was determined by the radioenzymatic measurement of erythrocyte membrane acetylcholinesterase (rbc-AChE) inhibition. Results The pharmacokinetic disposition of donepezil was observed to be both linear and dose proportional following single-dose administration. The mean peak plasma concentration (Cmax) of donepezil was observed at 4.1+/-1.5 h. The mean terminal disposition half-life was 81.5+/-22.0 h. The post-absorption phase of the plasma concentration-time curves for the 4.0 mg and 6.0 mg doses appeared to be biphasic, but the rate of donepezil clearance was independent of dose. Plasma concentrations for the 0.3, 0.6 and 0.9 mg dose groups were generally below the level of HPLC detection (2.0 ng ml(-1)), preventing accurate characterization of these doses. A direct correlation was observed between plasma donepezil concentrations and extent of AChE inhibition. For the 4.0 and 6.0 mg donepezil dose groups, maximal AChE inhibition (Emax) ranged from 33% to 35% and there was significant correlation between AChE inhibition and donepezil plasma concentration (P<0.005). Conclusions The pharmacokinetics of donepezil were found to be linear and dose proportional following the administration of single doses to healthy volunteers. A direct correlation was also observed between plasma donepezil concentrations and AChE inhibition. The extended half-life of donepezil makes it suitable for once-daily dosing.

Cite this study APA, Vancouver, BibTeX · download .bib or .ris

APA 7th

Rogers, S. L., & Friedhoff, L. T. (1998). Pharmacokinetic and pharmacodynamic profile of donepezil HCl following single oral doses. British journal of clinical pharmacology. https://doi.org/10.1046/j.1365-2125.1998.0460s1001.x

Vancouver

Rogers SL, Friedhoff LT. Pharmacokinetic and pharmacodynamic profile of donepezil HCl following single oral doses. British journal of clinical pharmacology. 1998. doi:10.1046/j.1365-2125.1998.0460s1001.x. PMID: 9839758.

BibTeX

@article{rogers1998-9839758,
  author  = {Rogers, S. L. and Friedhoff, L. T.},
  title   = {{Pharmacokinetic and pharmacodynamic profile of donepezil HCl following single oral doses}},
  journal = {British journal of clinical pharmacology},
  year    = {1998},
  doi     = {10.1046/j.1365-2125.1998.0460s1001.x},
  pmid    = {9839758},
  url     = {https://doi.org/10.1046/j.1365-2125.1998.0460s1001.x}
}

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How to read this study

Design: this is a trial. Participants are assigned to a treatment or a comparison, so the key questions are who was enrolled, whether the comparison group got a placebo or nothing, how long people were followed, and whether the result is on a measure that matters to patients or on a biomarker. Open-label and small trials can overstate benefit.
Size: the record lists 48 participants. Ask whether that is enough for the question, and who they were.
Effect: the record gives no effect size, so the summary above cannot say how large any difference was.

What the evidence grade means here

This page is graded high. alzhub.org assigns the grade automatically from keywords in the abstract, not from reading the paper. High means the abstract mentions a randomized design, a meta-analysis or a systematic review. It can add at most 5 of the 100 points in the study score, and it is a label about design, not a verdict on whether the findings are true.

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Key findings

Results The pharmacokinetic disposition of donepezil was observed to be both linear and dose proportional following single-dose administration.
For the 4.0 and 6.0 mg donepezil dose groups, maximal AChE inhibition (Emax) ranged from 33% to 35% and there was significant correlation between AChE inhibition and donepezil plasma concentration (P<0.005).

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Study details

Participants48
Evidence strengthHigh

How this study scored 72/100

Published in a peer-reviewed journal, and it is a randomized controlled trial. Scored zero for effect reported because the record does not state it. We have no data on journal's citation record, times cited, citations per year, impact for its field and year, cited by studies here, still being cited, senior author's track record, institution's track record and multicenter collaboration, so those were left out: it earned 42 of the 58 points we could judge it on, which is 72 out of 100.

Component	Points	Why
Journal tier	7 / 10	Tier 3 — peer-reviewed journal (British journal of clinical pharmacology)
Journal's citation record	— / 4	No journal record from OpenAlex — left out of this score
Study design	11 / 12	A randomized controlled trial (from PubMed type “Randomized Controlled Trial”)
Strength of evidence	5 / 5	Rated “high” in our summary
Peer-review validation	10 / 10	Peer-reviewed. Published as an article in a named peer-reviewed journal.
How recent	1 / 5	1998 — older than 20 years, still counted
Sample size	1 / 4	48 participants
Effect reported	0 / 3	No effect size reported — scores zero (not stated in the record — scored 0)
Studied in people	3 / 3	Studied in people (participant count stated)
Randomized / blinded	2 / 2	Randomized and blinded or placebo-controlled (as stated in the record)
Times cited	— / 7	No citation count (not found in OpenAlex) — left out of this score
Citations per year	— / 5	No citation count or no year — left out of this score
Impact for its field and year	— / 6	No field-weighted citation impact (OpenAlex has none yet) — left out of this score
Cited by studies here	— / 6	Not yet checked against this library's citation graph — left out of this score
Still being cited	— / 4	No yearly citation counts — left out of this score
Senior author's track record	— / 4	Senior author's record not available — left out of this score
Institution's track record	— / 3	No institution listed in OpenAlex — left out of this score
Multicenter collaboration	— / 3	Institutions not listed — left out of this score
Indexed in PubMed	2 / 2	Indexed in PubMed (PMID 9839758)
Free to read	0 / 2	Behind a paywall — scores zero
Points	42 / 58	Scored on 11 of 20 parts. We have no data for the rest, so they are left out: 42 of the 58 points we could judge it on is 72 out of 100.
Total	72 / 100	—

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Where this led: Donepezil on the treatments page — its current status, approval date, side-effect rate and list price, kept up to date.

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