- Email: [email protected]
Individualising symptomatic therapy: N-of-1 trials
Poster Presentation:
pi&J
S165
DETECTION OF TAU PIIOSPHORYLATED AT THEONINE 231 IN HUMAN BRAIN EXTRACTS AND CEREBROSPINAL FLUID.
Russell
E Kohnkm.
Ludwig
Muximilianv
Kerkman,
John
IL;
Davies,
Peter
Ludwig
Drug Studies I
Molecular
DeBemurdis, Albert
Mmimrlrans
Geriafrirs
of Munich.
Univ
Jifung Einstein
i/nil:
Carp,
Munich Shm. Co//
of Munich,
Vunon
Hills, IL; Kutharinu
Germany;
Molecular
Raymond Geriatrics
of Medicine.
Munich
Bronx.
Buerger,
Zinkowski. Corp.
NY:
Dar&l
Vernon
Hamld
Hills,
Nakuguwa,
of Medicine.
Hasp,
Fukuoka
Fukuoka Fukuokn
Japan:
Maki Mental Kyushu
Japun:
Hosp.
Chikushino
Univ. Fukuoku Atsushi
Nobutada
Ichimiyr,
Tashiro.
Japan:
Japan; Masnshi
Institute
Gmduuutr
OF APOLIPOPROTEIN
Sch
Koji O,qomori, Takita,
of Health of
lmazu Sci,
Medicine.
E
Graduatr Red
Cross
Kyushu
Univ.
Kyushu
Univ.
INHERITED ALZHEIMER’S DISEASE-OLFACTORY 17481TION: A TEN YEAR FOLLOW-UP
In an
pi3J
ACETYLCHOLINESTERASE NICOTINIC RECEPTORS
Dianu
S Woodruff-Pak,
Wenk,
Univ
Richurd
of Arizona,
Tucson,
W Vogel,
INHIBITION,
Temple
LEARNING,
Univ. Philadelphia,
PA;
AND
Gary
L
AZ
Eyeblink classical conditioning ia a form of associative learning that is Impaired m normal aging in rats, rabbits, cats, and humans. Alzheimer’a disease (AD) impair5 eyeblink conditioning beyond the effects of normal aging likely due to the disruption of the hippocampal cholinergic system. Drugs currently awlable for the clinical treatment of memory impairment in AD are acetylcholinesterase (AChE) inhibitors that increase brain acetylcholine levels. Recent results suggest that daily administration of these drugs results in an increase the number of nicotinic cholinergic receptors. Because nicotinic cholinergic receptors are lost in AD, mcreasing the number of these receptors has a potentially significant therapeutic effect. We tested the cognitionenhancing effects of two AChE inhibitors, galantamine and donepezil in older rabbits using the eyeblink classical conditioning paradigm. Rabbits received daily injections of AChE inhibitors for a minimum of 15 days and a maximum of 90 days. Leaning was significantly improved in AChE-treated older rabbits over rabbits treated with sterile saline vehicle, and blood AChE levels were significantly reduced. In young rabbits treated with the nicotinic antagonist, mecamylamine along with galantamine or donepezil, the deleterious effect of mecamylamine was reversed. Analysis is underway using epibatidine to define the sites of nicotinic binding in older rabbits treated with galantamine for 15 or 90 days. It is anticipated that the daily administration of galantamine will produce an increase in mcotmtc sate density.
Japm
Apolipoprotein E (Apo E) e4 allele ia known to be a genetic risk factor in dementia of the Alzheimer type (DAT) (I). Many investigators have studied the relationship between Apo E e4 allele and dementia other than DAT (2). In the previous World Alzheimer Congress held in Amsterdam, we reported the relationship between Apo E e4 allele and dementia such as frontotemporal dementia, dementia of the Alzheimer’s type and vascular dementia in Japan. We also reported a simple method for detection of apolipoprotein E e2 allele using the modified protocol of H&on and Vernier. (3) in order to avoid misleading or incomplete digestion of a band of 81 bp which should be separated to two bands of 48 bp and 33 bp by Hae 11 enzyme (4). We now developed a simple method for detection of apolipoprotein E e4 allele using the polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). This method facilitates clear discrimination between e4 and e2 or e3 alleles hince we USCagaroae gel instead of polyacrylamide gel. We would like to introduce you to this simple method at World Alzhetmer Congress 2000. 1 Saunders, A. M.. Strittmatter, W. J. , Schmechel, D. , George-Hyslop, P. H. St., Pencak-Vance, M.A., Jo”, S.H., Rest, B. L. , Gusella, J. F. . Crapper-MacLachlan, D.R., Alberts, M.J., Hulette, C., Grain. B., Goldgaber. D. and Roses, A.D., Association of apolipoprotein E allele e4 with late-onset familial and sporadic Alrheimer’s disease, Neurology, 43 (1993) 1467.1472. 2 Nakagawa Y, et al.. Apolipoprotein E in Creutzfeldt-Jakob disease. Lancet., 345 (1995) 68. 3 Hixson, J.E. and Vernier, D.T., Restriction notyping of human apolipoprotein E by gene amplification and cleavage with HhaI, J. Lipid. Res., 31 (1990) 545-548. 4 Nakagawa Y. et al.. Allelic variation of apolipoprotein E in Japanere rporadic CreutLfeldt-Jakob disease patients. Neurorci Lett... 1X7(1995):209-1 I.
I.inda
Drug Studies I
Grrmun~
A SIMPLE METHOD FOR DETECTION E4 ALLELE Yawshi
Poster Presentation:
Hamprl,
Tau protein phosphorylation and accumulation in the form of paired helical filaments ib a common pathological feature found in Alzheimer’s disease (AD) brain. Tao protein in cerebrospinal fluid has been repotted to be elevated in AD, but also in other neurodegenerative diseases. We have developed an assay which detects phosphotau in the hope that it might prove more diagnostic for AD. In this study, we describe a new sandwich ELISA in which tau is ca ptured wth two backbone-directed antibodies, taul and cp27. The captured tau is detected wth an antibody, cpY, that is specific for tau phosphorylated at threonine 231. In an analysis of brain extracts from AD and other dementia, five of’six AD samples were elevated relative to controls whereas zero samples out of twenty-five from other dementias were elevated. Fifty-eight antemortem cerebrospinal fluid sampler were then analyred. Twenty-three of twentyseven AD samples (85% sensitivity) yielded signals greater than a cutoff value, while only one of thirty-one non-AD samples (97% specificity) were greater. These data Indicate that detection of phosphotau in cerebrospinal fluid could prove useful in the diagnosis of AD.
Sch
the 3 individuals who had negative results before their dementia. The follow-up data IS in the process of being analyzed.
Elizabeth
Nre.
Nind.vNih.
Bethesda,
FUNC-
MD
effort to identify a biological marker useful for the clinical diagnosis of Alzheimer’s Disease, ten years ago we gave the self-administered commercially available 40 question scratch and sniff Smell Identification Test (Richard L. Doty, Sensonics, Inc.NJ) to 18 at-risk family members with autosomal dominantly inherited Alzheimer Disease. It wab later determined that this family had the presenilin-I mutation on chromosome 14. Testing was normal 10 years ago except for one individual who had smoked 3 packs of cigarettes a day for more than 23 years. Four family members tested in 1990 are now demented including the smoker. The mean age of the population is now 45 years with a range of 32 to 64. The mean age of onset m this family is 49 yews with a range of 39 to 58. The smell test in 1990 did not demonstrate predictive capacity years before clinical conversion to dementia. The quation for the follow-up study is whether the test will have converted to positive in
piJ Nrwah
lNDlVlDUALlSlNG
Qizilbu%h.
Cmtoblnnco,
O@rd
Madrid
Univ.
SYMPTOMATIC
Oxford
United
THERAPY: N-OF-1 TRIALS
Kingdom:
Jews
L Arrirm,
Hasp,
Spain
Traditional trial designs have established the efficacy and safety of cholinesterase inhibitors for symptomatic treatment of Alzheimer’\ disease but they provide only average results, which may not apply to a particular mdividual patient. We are unable to predict who will and will not benefit from subgroup analyses. Many patients do not henetit from cholinresterase inhibitors and many benefit to varying degrees. Therefore, individualization of therapy is essential. It may also be a way to convince health purchasers to buy or allow reimbursement. Minor bide effecta may also be evaluated with this design. Uncontrolled clinical observation lacks the controlled condttiom required to reduce the sources of substantial variation, overcome placebo effects, regression to the mean, the natural history of the disease and the prejudices of patients, carers and clinicians. Of patients with Alzheimer’s diseaw in the placebo groups of the tacrine trials, about 20% scored better at 30 weeks on the Clinical Interview-based Impression scale, when compared to baseline. Stopping therapy, when treatment may cease to offer any benefits can also be assessed by modifications m the practical derign of the n-of-l trial. Prescribing cholinesterase inhibitors for types of pattents who were not represented in the trials also should be done within a n-of-l design. The conditions for using an n-of-l design apply to dementia (though rapidly detenorating cases may serve as exceptions) over the short to medium t&l. There is substantial uncertainty over who will benefit, the condition is chronic and relatively stable over the short to medium term, the effects of treatment develop and abate over several weeks, the target symptoms are realtively stable and any carry over effect ha5 subsided by the next assessment. The minor decline in cognition over a few months can be modelled in the analyst The practcalities of conducting n-of-l trials will be discussed for the design features, outcome measures, analysis and ethics.
pi&J
S165
DETECTION OF TAU PIIOSPHORYLATED AT THEONINE 231 IN HUMAN BRAIN EXTRACTS AND CEREBROSPINAL FLUID.
Russell
E Kohnkm.
Ludwig
Muximilianv
Kerkman,
John
IL;
Davies,
Peter
Ludwig
Drug Studies I
Molecular
DeBemurdis, Albert
Mmimrlrans
Geriafrirs
of Munich.
Univ
Jifung Einstein
i/nil:
Carp,
Munich Shm. Co//
of Munich,
Vunon
Hills, IL; Kutharinu
Germany;
Molecular
Raymond Geriatrics
of Medicine.
Munich
Bronx.
Buerger,
Zinkowski. Corp.
NY:
Dar&l
Vernon
Hamld
Hills,
Nakuguwa,
of Medicine.
Hasp,
Fukuoka
Fukuoka Fukuokn
Japan:
Maki Mental Kyushu
Japun:
Hosp.
Chikushino
Univ. Fukuoku Atsushi
Nobutada
Ichimiyr,
Tashiro.
Japan:
Japan; Masnshi
Institute
Gmduuutr
OF APOLIPOPROTEIN
Sch
Koji O,qomori, Takita,
of Health of
lmazu Sci,
Medicine.
E
Graduatr Red
Cross
Kyushu
Univ.
Kyushu
Univ.
INHERITED ALZHEIMER’S DISEASE-OLFACTORY 17481TION: A TEN YEAR FOLLOW-UP
In an
pi3J
ACETYLCHOLINESTERASE NICOTINIC RECEPTORS
Dianu
S Woodruff-Pak,
Wenk,
Univ
Richurd
of Arizona,
Tucson,
W Vogel,
INHIBITION,
Temple
LEARNING,
Univ. Philadelphia,
PA;
AND
Gary
L
AZ
Eyeblink classical conditioning ia a form of associative learning that is Impaired m normal aging in rats, rabbits, cats, and humans. Alzheimer’a disease (AD) impair5 eyeblink conditioning beyond the effects of normal aging likely due to the disruption of the hippocampal cholinergic system. Drugs currently awlable for the clinical treatment of memory impairment in AD are acetylcholinesterase (AChE) inhibitors that increase brain acetylcholine levels. Recent results suggest that daily administration of these drugs results in an increase the number of nicotinic cholinergic receptors. Because nicotinic cholinergic receptors are lost in AD, mcreasing the number of these receptors has a potentially significant therapeutic effect. We tested the cognitionenhancing effects of two AChE inhibitors, galantamine and donepezil in older rabbits using the eyeblink classical conditioning paradigm. Rabbits received daily injections of AChE inhibitors for a minimum of 15 days and a maximum of 90 days. Leaning was significantly improved in AChE-treated older rabbits over rabbits treated with sterile saline vehicle, and blood AChE levels were significantly reduced. In young rabbits treated with the nicotinic antagonist, mecamylamine along with galantamine or donepezil, the deleterious effect of mecamylamine was reversed. Analysis is underway using epibatidine to define the sites of nicotinic binding in older rabbits treated with galantamine for 15 or 90 days. It is anticipated that the daily administration of galantamine will produce an increase in mcotmtc sate density.
Japm
Apolipoprotein E (Apo E) e4 allele ia known to be a genetic risk factor in dementia of the Alzheimer type (DAT) (I). Many investigators have studied the relationship between Apo E e4 allele and dementia other than DAT (2). In the previous World Alzheimer Congress held in Amsterdam, we reported the relationship between Apo E e4 allele and dementia such as frontotemporal dementia, dementia of the Alzheimer’s type and vascular dementia in Japan. We also reported a simple method for detection of apolipoprotein E e2 allele using the modified protocol of H&on and Vernier. (3) in order to avoid misleading or incomplete digestion of a band of 81 bp which should be separated to two bands of 48 bp and 33 bp by Hae 11 enzyme (4). We now developed a simple method for detection of apolipoprotein E e4 allele using the polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). This method facilitates clear discrimination between e4 and e2 or e3 alleles hince we USCagaroae gel instead of polyacrylamide gel. We would like to introduce you to this simple method at World Alzhetmer Congress 2000. 1 Saunders, A. M.. Strittmatter, W. J. , Schmechel, D. , George-Hyslop, P. H. St., Pencak-Vance, M.A., Jo”, S.H., Rest, B. L. , Gusella, J. F. . Crapper-MacLachlan, D.R., Alberts, M.J., Hulette, C., Grain. B., Goldgaber. D. and Roses, A.D., Association of apolipoprotein E allele e4 with late-onset familial and sporadic Alrheimer’s disease, Neurology, 43 (1993) 1467.1472. 2 Nakagawa Y, et al.. Apolipoprotein E in Creutzfeldt-Jakob disease. Lancet., 345 (1995) 68. 3 Hixson, J.E. and Vernier, D.T., Restriction notyping of human apolipoprotein E by gene amplification and cleavage with HhaI, J. Lipid. Res., 31 (1990) 545-548. 4 Nakagawa Y. et al.. Allelic variation of apolipoprotein E in Japanere rporadic CreutLfeldt-Jakob disease patients. Neurorci Lett... 1X7(1995):209-1 I.
I.inda
Drug Studies I
Grrmun~
A SIMPLE METHOD FOR DETECTION E4 ALLELE Yawshi
Poster Presentation:
Hamprl,
Tau protein phosphorylation and accumulation in the form of paired helical filaments ib a common pathological feature found in Alzheimer’s disease (AD) brain. Tao protein in cerebrospinal fluid has been repotted to be elevated in AD, but also in other neurodegenerative diseases. We have developed an assay which detects phosphotau in the hope that it might prove more diagnostic for AD. In this study, we describe a new sandwich ELISA in which tau is ca ptured wth two backbone-directed antibodies, taul and cp27. The captured tau is detected wth an antibody, cpY, that is specific for tau phosphorylated at threonine 231. In an analysis of brain extracts from AD and other dementia, five of’six AD samples were elevated relative to controls whereas zero samples out of twenty-five from other dementias were elevated. Fifty-eight antemortem cerebrospinal fluid sampler were then analyred. Twenty-three of twentyseven AD samples (85% sensitivity) yielded signals greater than a cutoff value, while only one of thirty-one non-AD samples (97% specificity) were greater. These data Indicate that detection of phosphotau in cerebrospinal fluid could prove useful in the diagnosis of AD.
Sch
the 3 individuals who had negative results before their dementia. The follow-up data IS in the process of being analyzed.
Elizabeth
Nre.
Nind.vNih.
Bethesda,
FUNC-
MD
effort to identify a biological marker useful for the clinical diagnosis of Alzheimer’s Disease, ten years ago we gave the self-administered commercially available 40 question scratch and sniff Smell Identification Test (Richard L. Doty, Sensonics, Inc.NJ) to 18 at-risk family members with autosomal dominantly inherited Alzheimer Disease. It wab later determined that this family had the presenilin-I mutation on chromosome 14. Testing was normal 10 years ago except for one individual who had smoked 3 packs of cigarettes a day for more than 23 years. Four family members tested in 1990 are now demented including the smoker. The mean age of the population is now 45 years with a range of 32 to 64. The mean age of onset m this family is 49 yews with a range of 39 to 58. The smell test in 1990 did not demonstrate predictive capacity years before clinical conversion to dementia. The quation for the follow-up study is whether the test will have converted to positive in
piJ Nrwah
lNDlVlDUALlSlNG
Qizilbu%h.
Cmtoblnnco,
O@rd
Madrid
Univ.
SYMPTOMATIC
Oxford
United
THERAPY: N-OF-1 TRIALS
Kingdom:
Jews
L Arrirm,
Hasp,
Spain
Traditional trial designs have established the efficacy and safety of cholinesterase inhibitors for symptomatic treatment of Alzheimer’\ disease but they provide only average results, which may not apply to a particular mdividual patient. We are unable to predict who will and will not benefit from subgroup analyses. Many patients do not henetit from cholinresterase inhibitors and many benefit to varying degrees. Therefore, individualization of therapy is essential. It may also be a way to convince health purchasers to buy or allow reimbursement. Minor bide effecta may also be evaluated with this design. Uncontrolled clinical observation lacks the controlled condttiom required to reduce the sources of substantial variation, overcome placebo effects, regression to the mean, the natural history of the disease and the prejudices of patients, carers and clinicians. Of patients with Alzheimer’s diseaw in the placebo groups of the tacrine trials, about 20% scored better at 30 weeks on the Clinical Interview-based Impression scale, when compared to baseline. Stopping therapy, when treatment may cease to offer any benefits can also be assessed by modifications m the practical derign of the n-of-l trial. Prescribing cholinesterase inhibitors for types of pattents who were not represented in the trials also should be done within a n-of-l design. The conditions for using an n-of-l design apply to dementia (though rapidly detenorating cases may serve as exceptions) over the short to medium t&l. There is substantial uncertainty over who will benefit, the condition is chronic and relatively stable over the short to medium term, the effects of treatment develop and abate over several weeks, the target symptoms are realtively stable and any carry over effect ha5 subsided by the next assessment. The minor decline in cognition over a few months can be modelled in the analyst The practcalities of conducting n-of-l trials will be discussed for the design features, outcome measures, analysis and ethics.