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Monitoring Anti-Dementia Drugs by Serum Levels

Monitoring Anti-Dementia Drugs by Serum Levels: Importance of Serum Levels, Drug-monitoring, Side-effects, Clinical Efficacy and Compliance (Translation of Official Danish Title)

Status
Completed
Phases
Phase 4
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04117178
Acronym
MONANTI
Enrollment
132
Registered
2019-10-07
Start date
2020-02-04
Completion date
2023-02-16
Last updated
2025-02-10

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Alzheimer Disease, Dementia, Dementia Alzheimers, Dementia in Parkinsons Disease, Dementia With Lewy Bodies

Keywords

Therapeutic Drug Monitoring, TDM, Adverse effects, Dementia, Alzheimer's disease

Brief summary

The main objective of the MONANTI study is twofold: Firstly, to determine the serum concentration (SC) the anti-dementia drugs donepezil and memantine in a broadly defined clinical population of patients suffering from dementia treated with the two drugs in question. Secondly, to determine whether adjustment of treatment of anti-dementia medication based on measurements of the SC will benefit patients in terms of cognitive performance, activities of daily living (ADL), frequency and severity of side effects. The reason for conduction of this study is that the relationship between serum-level of anti-dementia drugs, clinical efficacy, compliance and side effects has only been scarcely investigated. Both a previously published study and a preliminary (pilot)study conducted imply that roughly 50 % of patients on donepezil have SC outside the recommended therapeutic reference range (TRR). Thus, MONANTI will investigate if this is indeed the case in a broadly comprised population of patients with dementia treated with donepezil or memantine. In addition, MONANTI will link SC to co-morbidity, level of compliance, medication interactions. It is hypothesized that the efficacy of anti-dementia drugs can be significantly improved by adjustment of treatment according to SC. Also, it is hypothesized that the burden of side effects can be reduced in patients in whom too high SC are detected, if dose reduction or change of treatment drug is done. MONANTI is a randomized study, in which the assessor is blinded to avoid related biases to the extent possible. To meet the enrollment criteria eligible participants must: A) be newly diagnosed with either Alzheimer's disease dementia, dementia with Lewy-bodies or Parkinson's disease with dementia and B) be scheduled for treatment with either donepezil or memantine. C) not meet a list of (exclusion) criteria, which have been set up in order to avoid blur and biases of the results. D) be able to give written informed consent to participation in presence of a close relative. After enrollment the participants will be randomly assigned to one of two study groups. In the first of these, the control group, the participants receive standard treatment and follow-up at the outpatient clinic. In addition, all participants in the control group who complete the trial will have a blood sample collected at the final visit to measure the SC of the anti-dementia drug along with a genetic test for a few key genes thought to be relevant for the study (two liver enzymes (cyp2D6, cyp3A4/5, APOE-genotype, butyrylcholine-esterase K-variant). In the other group, the intervention group, the participators will be closely monitored for side effects after prescription of anti-dementia drugs. All participants in the intervention group will be offered a measurement of the SC in case they experience drug side effects within 2 months of treatment initiation. All participants in the intervention group will have a measurement of the SC done at the 6 months visit. The measured SC will be compared to the TRR of the drug in question. This information, along with details from the clinical assessment at the 6 month visit will be used to guide the decision of whether or not to adjust treatment. All decisions on treatment adjustment during the trial are done by the PI according to details in the protocol. All participants in the intervention group are evaluated again at a 12 month visit, identical to that of the control groups. To assess the possible effects of SC guided treatment adjustment six clinical tests/rating scales will be used (MMSE, ACE, NPI-Q, DAD, CGI, GDS). The tests/rating scales will be administered both at the enrollement visit and one year later at the final 12 month follow-up visit. To measure the effect of donepezil on brain cholinergic function approx. 30 participants will be recruited for electroencephalography (EEG). These participants will have an EEG done at enrollment and after 12 months. In addition to the above mentioned quantitative study a qualitative study with relatives of enrolled participants is planned. All the needed approvals have been obtained according to Danish law (approval by the Danish Data Protection Agency, Scientific Ethics Committee for Region Sjaelland, The Danish Medical Agencies).

Interventions

DRUGDonepezil

Adjustment of treatment with donepezil according to serum level.

DRUGMemantine

Adjustment of treatment with memantine according to serum level.

DIAGNOSTIC_TESTMeasurement of serum level of anti-dementia drug

Participants allocated to the intervention arm are requested to inform the sponsor of any side effects up to 2 months after prescription of the anti-dementia drug. If so, they will have their treatment adjusted according to the serum level. Participants in the intervention group not experiencing side effects will have their treatment adjusted after 6 months based upon serum levels of the drug in question. Participants allocated to the standard of care arm follow the usual routines of the dementia clinic but are requested to have the serum level of the prescribed drug and CYP2D6-genotype measured after 12 month.

Sponsors

Filadelfia Epilepsy Hospital
CollaboratorOTHER
Zealand University Hospital
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Investigator)

Intervention model description

Single blinded, randomized study with two arms: 'standard of care' arm and 'intervention' arm. Participants in the intervention arm will have their treatment adjusted according to Serum levels of the anti-dementia drug prescribed.

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

The following 3 inclusion criteria (A+B+C) must be met: A. Participant must be newly diagnosed with one of the three conditions below * Alzheimer's disease dementia * dementia with Lewy Bodies * Dementia in Parkinson's disease B. Participant must be prescribed either donepezil or memantine at enrollment. C. Participant must be able to give informed consent to participation in the study.

Exclusion criteria

* no accompanying relative at the enrollment and/or follow-up visits * patients living alone who do not receive help to administer medication. * lack of ability to cooperate, including severely reduced vision or impaired hearing and/or other severe disabilities. * patients unable to give informed consent in a meaningful sense due to cognitive decline at enrollment. * known psychiatric disease (schizophrenia, bipolar affective disorder etc.). However, patients suffering from depression are eligible if they have been in continuously medically treated for at least 3 months prior to enrollment. * known neurologic disorder, which by it self could contribute to cognitive symptoms. * other known medical condition (kidney-, liver-, metabolic disease etc.) which by itself could contribute to cognitive symptoms. * treatment with anti-psychotic drugs within 3 months of possible enrollment. A minimal daily dosage of benzodiazepine is deemed permissable for enrollment. * patients with a history of substantial previous abuse of alcohol or drugs. Also, any kind of substance abuse within last 3 months. * any previous severe trauma to the head or neuroinfections which could contribute to cognitive symptoms. * electro convulsive treatment within last 3 months. * anesthesia within last 3 months

Design outcomes

Primary

MeasureTime frameDescription
Level of Compliance to TreatmentLevel of compliance will be scored at the one year follow-up by both questioning the participant and the primary relative.The level to which the medication has been ingested as prescribed. Both the participant him/her self is questioned as is the primary relative. The level of compliance is rated as belonging to one of the four categories: 1) 'completely regular drug intake' (no missed daily doses within 6 months), 2 'regular drug intake' (less than 10 missed daily doses within 6 months), 3) 'less regular drug intake' (10 - 30 missed daily doses with 6 months), 4) 'irregular drug intake' (more than 30 missed daily doses within 6 months)
Change of Mini Mental State Examination (MMSE) Test Result1 year (enrollment in study and at 1-year follow-up)Widely used clinical test for brief assesment of cognitive function. Total score ranging from 0 (worst) to 30 (best).
Change of Adenbrooke's Cognitive Examination (ACE) Test Result1 year (enrollment in study and at 1-year follow-up)Widely used clinical test for assesment of cognitive function. The total score ranges from 0 (worst) 100 (best) and includes the score of the MMSE test (0-30).
Percentage of Participants With a Serum Concentration Within the Therapeutic Reference Range (TRR) at 12 Month Follow-up Visit.Counted at the 12 month visitPercentage of participans in each group with serum concentrations of the study drugs within the therapeutic reference range (TRR) at the 12 month follow-up visit. According to the 2017 AGNP consensus guidelines the TRRs are ranges of drug concentrations in blood that specify a lower limit below which a drug induced therapeutic response is relatively unlikely to occur and an upper limit above which tolerability decreases or above which it is relatively unlikely that therapeutic improvement may be still enhanced (Pharmacopsychiatry . 2018 Jan;51(1-02):9-62. doi: 10.1055/s-0043-116492. Epub 2017 Sep 14). Donepezil has a serum TRR of 50-75 nanograms per milliliter (ng/mL) and memantine has a serum TRR of 90-150 ng/mL.

Secondary

MeasureTime frameDescription
Change of Neuropsychiatric Inventory Questionnaire (NPI-Q) Score Result1 year (enrollment in study and at 1-year follow-up)A questionaire filled in by the primary relative of the participant. NPI-Q measures the severity of neuropsychiatric symptoms of demented patients. The total score ranges between 0 (best) and (36 worst).
Genetic Test for BcHE K VariantFor participants in the standard of care arm BcHE K variant status will be tested 1 year after enrollment. For participants in the intervention arm BcHE K variant status will be determined at the 6 month follow-up.BcHE butyryl cholinesterase (BChE), K variant.
C2D6 PhenotypeFor participants in the standard of care arm CYP2D6 status will be determined 1 year after enrollment. For participants in the intervention arm Cyp2D6 will be tested within 2 months if side effects are experienced, if not then after 6 months.Cyp2D6 is the gene which expresses the enzyme CYP2D6. Donepezil is metabolized by CYP2D6.
Change of Clinical Global Impression (CGI) Score Result1 year (enrollment in study and at 1-year follow-up)The overall clinical impression of the clinical response to treatment as assessed by the investigator. Ranges from 1 (very much improved) to 7 (very much worse).
Change in Geriatric Depression Scale (GDS) Symptoms ScoreThe GDS is administered to all participants at the both the baseline and 12-month follow-up visit.The Geriatric Depression Scale (GDS) is a questionaire administered by the investigator to the participant. GDS is used to assess symptoms of depression in the elderly. A 15 item version of the GDS is used with a score from 0 (best) to 15 (worst).
Change of Disability Assessment for Dementia (DAD) Score Result1 year (enrollment in study and at 1-year follow-up)A questionaire filled in by the primary relative of the participant. DAD measures the impact of dementia symptoms on activities of daily living (ADL), including eating, dressing, personal hygiene. Total score ranges from 0 (worst) to 40 (best)

Other

MeasureTime frameDescription
Genetic Test for APOe4 Allele Status.For participants who complete the trial APOe4 allele status is assessed at the 1 year visit.The APOe4 allele is linked to an increased risk of developing Alzheimer's disease.

Countries

Denmark

Participant flow

Recruitment details

A total of 132 participants recruited because a total of 110 participants assessable at the 6 month visit were needed.

Participants by arm

ArmCount
Standard of Care
Participants allocated to this arm follow the usual routines of the out patient dementia clinic but are requested to have the serum level of the prescribed drug measured after 12 month. Also, CYP2D6, BcHE K and APOe4 status will be determined after 12 months. Measurement of serum level of anti-dementia drug: Participants allocated to the intervention arm are requested to inform the sponsor of any side effects up to 2 months after prescription of the anti-dementia drug. If so, they will have their treatment adjusted according to the serum level. Participants in the intervention group not experiencing side effects will have their treatment adjusted after 6 months based upon serum levels of the drug in question. Participants allocated to the standard of care arm follow the usual routines of the dementia clinic but are requested to have the serum level of the prescribed drug and CYP2D6-genotype measured after 12 month.
65
Intervention Arm
Participants allocated to this arm follow are requested to inform the sponsor of any side effects up to 2 months after prescription of the anti-dementia drug. If so, they will have their treatment adjusted according to the serum level. Participants in the intervention arm not experiencing side effects will have their treatment adjusted after 6 months based upon serum level of the drug in question. Donepezil: Adjustment of treatment with donepezil according to serum level. Memantine: Adjustment of treatment with memantine according to serum level. Measurement of serum level of anti-dementia drug: Participants allocated to the intervention arm are requested to inform the sponsor of any side effects up to 2 months after prescription of the anti-dementia drug. If so, they will have their treatment adjusted according to the serum level. Participants in the intervention group not experiencing side effects will have their treatment adjusted after 6 months based upon serum levels of the drug in question. Participants allocated to the standard of care arm follow the usual routines of the dementia clinic but are requested to have the serum level of the prescribed drug and CYP2D6-genotype measured after 12 month.
67
Total132

Baseline characteristics

CharacteristicIntervention ArmTotalStandard of Care
Age, Categorical
<=18 years
0 Participants0 Participants0 Participants
Age, Categorical
>=65 years
58 Participants116 Participants58 Participants
Age, Categorical
Between 18 and 65 years
9 Participants16 Participants7 Participants
Age, Continuous74.4 years
STANDARD_DEVIATION 8.1
75.2 years
STANDARD_DEVIATION 8
76.0 years
STANDARD_DEVIATION 8
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Asian
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Black or African American
0 Participants0 Participants0 Participants
Race (NIH/OMB)
More than one race
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants
Race (NIH/OMB)
White
67 Participants132 Participants65 Participants
Region of Enrollment
Denmark
67 participants132 participants65 participants
Sex: Female, Male
Female
21 Participants58 Participants37 Participants
Sex: Female, Male
Male
46 Participants74 Participants28 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
2 / 652 / 67
other
Total, other adverse events
42 / 6546 / 67
serious
Total, serious adverse events
6 / 657 / 67

Outcome results

Primary

Change of Adenbrooke's Cognitive Examination (ACE) Test Result

Widely used clinical test for assesment of cognitive function. The total score ranges from 0 (worst) 100 (best) and includes the score of the MMSE test (0-30).

Time frame: 1 year (enrollment in study and at 1-year follow-up)

ArmMeasureValue (MEAN)Dispersion
Standard of CareChange of Adenbrooke's Cognitive Examination (ACE) Test Result-3.76 difference in ACE units on a scaleStandard Deviation 6.56
Intervention ArmChange of Adenbrooke's Cognitive Examination (ACE) Test Result-4.02 difference in ACE units on a scaleStandard Deviation 9.01
Primary

Change of Mini Mental State Examination (MMSE) Test Result

Widely used clinical test for brief assesment of cognitive function. Total score ranging from 0 (worst) to 30 (best).

Time frame: 1 year (enrollment in study and at 1-year follow-up)

ArmMeasureValue (MEAN)Dispersion
Standard of CareChange of Mini Mental State Examination (MMSE) Test Result-0.27 difference in MMSE units on a scaleStandard Deviation 3.19
Intervention ArmChange of Mini Mental State Examination (MMSE) Test Result-0.90 difference in MMSE units on a scaleStandard Deviation 3.56
Primary

Level of Compliance to Treatment

The level to which the medication has been ingested as prescribed. Both the participant him/her self is questioned as is the primary relative. The level of compliance is rated as belonging to one of the four categories: 1) 'completely regular drug intake' (no missed daily doses within 6 months), 2 'regular drug intake' (less than 10 missed daily doses within 6 months), 3) 'less regular drug intake' (10 - 30 missed daily doses with 6 months), 4) 'irregular drug intake' (more than 30 missed daily doses within 6 months)

Time frame: Level of compliance will be scored at the one year follow-up by both questioning the participant and the primary relative.

ArmMeasureCategoryValue (COUNT_OF_PARTICIPANTS)
Standard of CareLevel of Compliance to TreatmentCompletely regular48 Participants
Standard of CareLevel of Compliance to TreatmentRegular1 Participants
Standard of CareLevel of Compliance to TreatmentLess regular0 Participants
Standard of CareLevel of Compliance to TreatmentIrregular0 Participants
Intervention ArmLevel of Compliance to TreatmentIrregular0 Participants
Intervention ArmLevel of Compliance to TreatmentCompletely regular55 Participants
Intervention ArmLevel of Compliance to TreatmentLess regular2 Participants
Intervention ArmLevel of Compliance to TreatmentRegular1 Participants
Primary

Percentage of Participants With a Serum Concentration Within the Therapeutic Reference Range (TRR) at 12 Month Follow-up Visit.

Percentage of participans in each group with serum concentrations of the study drugs within the therapeutic reference range (TRR) at the 12 month follow-up visit. According to the 2017 AGNP consensus guidelines the TRRs are ranges of drug concentrations in blood that specify a lower limit below which a drug induced therapeutic response is relatively unlikely to occur and an upper limit above which tolerability decreases or above which it is relatively unlikely that therapeutic improvement may be still enhanced (Pharmacopsychiatry . 2018 Jan;51(1-02):9-62. doi: 10.1055/s-0043-116492. Epub 2017 Sep 14). Donepezil has a serum TRR of 50-75 nanograms per milliliter (ng/mL) and memantine has a serum TRR of 90-150 ng/mL.

Time frame: Counted at the 12 month visit

ArmMeasureCategoryValue (COUNT_OF_PARTICIPANTS)
Standard of CarePercentage of Participants With a Serum Concentration Within the Therapeutic Reference Range (TRR) at 12 Month Follow-up Visit.Within TRR23 Participants
Standard of CarePercentage of Participants With a Serum Concentration Within the Therapeutic Reference Range (TRR) at 12 Month Follow-up Visit.Outside TRR26 Participants
Intervention ArmPercentage of Participants With a Serum Concentration Within the Therapeutic Reference Range (TRR) at 12 Month Follow-up Visit.Within TRR23 Participants
Intervention ArmPercentage of Participants With a Serum Concentration Within the Therapeutic Reference Range (TRR) at 12 Month Follow-up Visit.Outside TRR35 Participants
Secondary

C2D6 Phenotype

Cyp2D6 is the gene which expresses the enzyme CYP2D6. Donepezil is metabolized by CYP2D6.

Time frame: For participants in the standard of care arm CYP2D6 status will be determined 1 year after enrollment. For participants in the intervention arm Cyp2D6 will be tested within 2 months if side effects are experienced, if not then after 6 months.

ArmMeasureCategoryValue (COUNT_OF_PARTICIPANTS)
Standard of CareC2D6 PhenotypeUltrafast metabolizer0 Participants
Standard of CareC2D6 PhenotypeExtensive metabolizer42 Participants
Standard of CareC2D6 PhenotypeIntermediate metabolizer5 Participants
Standard of CareC2D6 PhenotypePoor metabolizer2 Participants
Intervention ArmC2D6 PhenotypePoor metabolizer3 Participants
Intervention ArmC2D6 PhenotypeUltrafast metabolizer1 Participants
Intervention ArmC2D6 PhenotypeIntermediate metabolizer5 Participants
Intervention ArmC2D6 PhenotypeExtensive metabolizer49 Participants
Secondary

Change in Geriatric Depression Scale (GDS) Symptoms Score

The Geriatric Depression Scale (GDS) is a questionaire administered by the investigator to the participant. GDS is used to assess symptoms of depression in the elderly. A 15 item version of the GDS is used with a score from 0 (best) to 15 (worst).

Time frame: The GDS is administered to all participants at the both the baseline and 12-month follow-up visit.

ArmMeasureValue (MEAN)Dispersion
Standard of CareChange in Geriatric Depression Scale (GDS) Symptoms Score-0.57 units on a scaleStandard Deviation 2.47
Intervention ArmChange in Geriatric Depression Scale (GDS) Symptoms Score0.79 units on a scaleStandard Deviation 2.55
Secondary

Change of Clinical Global Impression (CGI) Score Result

The overall clinical impression of the clinical response to treatment as assessed by the investigator. Ranges from 1 (very much improved) to 7 (very much worse).

Time frame: 1 year (enrollment in study and at 1-year follow-up)

ArmMeasureValue (MEAN)Dispersion
Standard of CareChange of Clinical Global Impression (CGI) Score Result4.68 score on a scaleStandard Deviation 1.06
Intervention ArmChange of Clinical Global Impression (CGI) Score Result4.62 score on a scaleStandard Deviation 0.95
Secondary

Change of Disability Assessment for Dementia (DAD) Score Result

A questionaire filled in by the primary relative of the participant. DAD measures the impact of dementia symptoms on activities of daily living (ADL), including eating, dressing, personal hygiene. Total score ranges from 0 (worst) to 40 (best)

Time frame: 1 year (enrollment in study and at 1-year follow-up)

ArmMeasureValue (MEAN)Dispersion
Standard of CareChange of Disability Assessment for Dementia (DAD) Score Result-0.07 difference in DAD units on a scaleStandard Deviation 0.13
Intervention ArmChange of Disability Assessment for Dementia (DAD) Score Result-0.10 difference in DAD units on a scaleStandard Deviation 0.16
Secondary

Change of Neuropsychiatric Inventory Questionnaire (NPI-Q) Score Result

A questionaire filled in by the primary relative of the participant. NPI-Q measures the severity of neuropsychiatric symptoms of demented patients. The total score ranges between 0 (best) and (36 worst).

Time frame: 1 year (enrollment in study and at 1-year follow-up)

ArmMeasureValue (MEAN)Dispersion
Standard of CareChange of Neuropsychiatric Inventory Questionnaire (NPI-Q) Score Result2.40 difference in NPI units on a scaleStandard Deviation 6.34
Intervention ArmChange of Neuropsychiatric Inventory Questionnaire (NPI-Q) Score Result1.30 difference in NPI units on a scaleStandard Deviation 3.18
Secondary

Genetic Test for BcHE K Variant

BcHE butyryl cholinesterase (BChE), K variant.

Time frame: For participants in the standard of care arm BcHE K variant status will be tested 1 year after enrollment. For participants in the intervention arm BcHE K variant status will be determined at the 6 month follow-up.

ArmMeasureCategoryValue (COUNT_OF_PARTICIPANTS)
Standard of CareGenetic Test for BcHE K VariantWildtype/Wildtype29 Participants
Standard of CareGenetic Test for BcHE K VariantWildtype/mutant18 Participants
Standard of CareGenetic Test for BcHE K Variantmutant/mutant2 Participants
Intervention ArmGenetic Test for BcHE K VariantWildtype/Wildtype37 Participants
Intervention ArmGenetic Test for BcHE K VariantWildtype/mutant18 Participants
Intervention ArmGenetic Test for BcHE K Variantmutant/mutant3 Participants
Other Pre-specified

Genetic Test for APOe4 Allele Status.

The APOe4 allele is linked to an increased risk of developing Alzheimer's disease.

Time frame: For participants who complete the trial APOe4 allele status is assessed at the 1 year visit.

ArmMeasureCategoryValue (COUNT_OF_PARTICIPANTS)
Standard of CareGenetic Test for APOe4 Allele Status.APOE2/APOE20 Participants
Standard of CareGenetic Test for APOe4 Allele Status.APOE2/APOE31 Participants
Standard of CareGenetic Test for APOe4 Allele Status.APOE2/APOE41 Participants
Standard of CareGenetic Test for APOe4 Allele Status.APOE3/APOE310 Participants
Standard of CareGenetic Test for APOe4 Allele Status.APOE3/APOE431 Participants
Standard of CareGenetic Test for APOe4 Allele Status.APOE4/APOE46 Participants
Intervention ArmGenetic Test for APOe4 Allele Status.APOE3/APOE428 Participants
Intervention ArmGenetic Test for APOe4 Allele Status.APOE2/APOE21 Participants
Intervention ArmGenetic Test for APOe4 Allele Status.APOE3/APOE317 Participants
Intervention ArmGenetic Test for APOe4 Allele Status.APOE2/APOE31 Participants
Intervention ArmGenetic Test for APOe4 Allele Status.APOE4/APOE410 Participants
Intervention ArmGenetic Test for APOe4 Allele Status.APOE2/APOE41 Participants

Source: ClinicalTrials.gov · Data processed: Feb 6, 2026