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Vitamin B6 in the treatment of tardive dyskinesia
04 October 2001
Results of a randomised controlled trial suggest vitamin B6 can reduce the symptoms of tardive dyskinesia (TD). Benefits of vitamin B6 in TD have been reported previously (see Vitamin B6 and tardive dyskinesia in people taking typical antipsychotics), but this is the first placebo-controlled trial to put vitamin B6 to the test. Fifteen people with schizophrenia or schizoaffective disorder with diagnostic criteria for TD were randomised to placebo or a regime of vitamin B6 starting at 100mg/day increasing weekly by 100mg to 400mg/day. Participants were crossed over halfway through the four-week study so that those initially on placebo were changed to vitamin B6 and vice versa. Assessments were made at baseline and once weekly and symptoms of TD were measured on the Parkinsonian, dystonia and dyskinetic subscales of the Extrapyramidal Symptom Scale. The researchers reported an average of 50% improvement in symptoms of TD.
Reference
Lerner V et al (2001) Vitamin B6 in the treatment of tardive dyskinesia: a double-blind, placebo-controlled, crossover study American Journal of Psychiatry 158:1511-14 Abstract
Trial to assess benefits of lipid-lowering therapy in Alzheimer's disease
03 October 2001
US researchers are testing a drug designed to reduce plasma cholesterol, atorvastatin (Pfizer's Lipitor) in Alzheimer's disease. The study, which is being funded jointly by the Institute for the Study of Aging and Pfizer, is the first of its kind to assess the therapeutic potential of a cholesterol-lowering agent in the treatment of Alzheimer's disease. There is evidence that high cholesterol levels may play a critical role in the neurodegenerative process, and although drugs are available to reduce cholesterol (collectively called statins), their effect in Alzheimer's has yet to be put to the test. The two-year trial will be placebo-controlled for one year; participants will then receive atorvastatin on an open-label basis. Led by Dr Larry Sparks at the Sun Health Research Institute in Arizona, researchers will test the effects of 80mg atorvastatin on a range of cognitive and functional measures in people with mild Alzheimer's disease.
Withdrawal of Baycol: concern about other statins?
14 September 2001
The recent withdrawal of Bayer's cerivastatin (Baycol or Lipobay), an HMG-CoA reductase inhibitor prescribed to lower blood cholesterol, has raised concerns about the safety of other statins. Apart from their proven role in protecting against cardiovascular problems, interest has been focused on accumulating evidence that they can also prevent Alzheimer's disease. Cerivastatin was recalled after 52 patients died from severe rhabdomyolysis, a musculo-degenerative disease. Those also taking gemifibrozil (Lopid and generics) appeared to be at even greater risk. Unwanted effects have been reported for the remaining statins (lovastatin, pravastatin, simvastatin, fluvastatin and atorvastatin), including cases of rhabdomyolysis when simvastatin is administered with clarithromycin. But evidence suggests these drugs are normally well tolerated. Some have been available for more than a decade. Some of Bayer's competitors have been quick to point this out and have scrambled to fill the hole left in the market. Full page advertisements touting the alternatives have recently appeared in American papers, as have interactive adverts in on-line editions (see for example the New York Times, www.newyorktimes.com).
More info: www.fda.gov/cder/drug/infopage/baycol/default.htm
AlzheimAlert: urine test for detection of Alzheimer's
14 September 2001
AlzheimAlert, a urine test claimed to diagnose Alzheimer's disease even in its early stages is available in the USA. An immunoassay developed by the Nymox Pharmaceutical Corporation, (Marywood New Jersey, and Saint Laurent, Quebec), the test measures levels of a 41 kD neural thread protein, AD7C-NTP, in patients' urine. Expression of AD7C-NTP and other neural thread protein species increases in early Alzheimer's disease, in some cases rising dramatically as the illness progresses. Some NTPs have been found associated with neurofibrillary tangles and early - but not mature - beta-amyloid deposits, and AD7C-NTP may have a role in initiating neurodegenerative apoptotic cascades. Previous tests for NTPs made use of cerebrospinal fluid, the extraction of which can be traumatic for patients. The urine test requires only 50 ml of first morning mid-stream urine. As yet the test is unavailable in kit form. See www.nymox.com
Long-acting risperidone filed with FDA
13 September 2001
Janssen Pharmaceutica has filed its long-acting formulation of risperidone for approval by the US FDA. A slow-release injectable formulation (which uses microsphere technology - extremely small particles made of a biodegradable polymer), a single injection is active for up to two weeks. If approved, it will provide an additional treatment option for people with schizophrenia. Long-acting risperidone - whose oral formulation is one of the one of the most widely used of the atypical antipsychotics - would bypass the need to take tablets every day, helping to improve medication compliance and reducing the chances of relapse. No other atypical antipsychotics are currently available in depot formulations - many of the older typical drugs are available in this form, but like their oral equivalents these are associated with severe side effects such as extrapyramidal effects. http://us.janssen.com/feature_articles/feature05022001.html
Bupropion shows promise in obesity
13 September 2001
Bupropion, a drug used for helping smokers quit (and also approved in the US as an antidepressant), has shown promise as a long-term treatment for obesity. A study published in Obesity Research found that obese women who used the drug in combination with a 1,600 calorie per day diet for up to two years lost significantly more weight than a group who stuck to the same diet but were taking a placebo. The findings could have implications for the treatment of obesity, which as well as being a major health risk has a reputation for being notoriously difficult to control in the long term. The mechanism of weight loss in relation to bupropion, however, remains unknown. http://www.obesityresearch.org/
Olanzapine injections can treat bipolar mania effectively
31 August 2001
In a randomized double-blind study of 201 people with bipolar mania, researchers have found that manic and agitated symptoms can be treated quickly and safely with intramuscular injections of olanzapine - an atypical antipsychotic. Although originally designed to treat psychotic episodes in schizophrenia, olanzapine has also shown a calming effect in people with acute bipolar mania. But quick-acting injectable atypical antipsychotics have only recently become available; oral preparations take longer to work. Agitated participants with bipolar mania received injections of one of three treatments: olanzapine, lorazepam or placebo - which were given in three doses over 24 hours. The therapeutic effect of olanzapine was statistically better than either placebo or lorazepam after 2 hours, with olanzapine-treated participants showing fewer symptoms of agitation, and was maintained after 24 hours. http://ipsapp001.lwwonline.com/servlet/GetFileServlet?J=3800&I=4&A=6&U=1&T=0
US expiry of Prozac patent
09 August 2001
US patents on Eli Lilly & Co.'s Prozac expired on 3 August 2001, enabling prescribers to choose cheaper generic competition. Barr Laboratories, a generics drugs manufacturer, has taken legal action to prevent an extension on Lilly's patent that would have ensured two more years of exclusive marketing. Prozac was the first available SSRI antidepressant, and has enjoyed worldwide success and household name status. But patents have been drying up around the world, and the company has been lucky to hang on to its biggest market, the US, for so long. Under US law, it was last year granted an extra six months exclusivity for conducting trials of the drug in children. UK Sales of Prozac dropped by 80% when patents expired last year, and analysts forecast a similar trend in US, where Prozac sales exceeded $2bn in 2000. After strong growth earlier in the year, Lilly is expecting profits to fall. Availability of a generic SSRI may also impact other pharmaceutical manufacturers. http://www.thetimes.co.uk/article/0,,5-2001260957,00.html
UK CSM to review SSRI antidepressants and suicide
30 June 2001
The UK Committee on Safety of Medicines (CSM) is to review alleged links between the SSRI antidepressants and suicide. David Healy, director of the North Wales department of Psychological Medicine at Gwynedd Hospital, has re-ignited claims that SSRIs may cause an increase in suicidal tendencies. Healy was expert witness in a landmark US ruling that linked both suicide and homicide to an SSRI (paroxetine). He has also conducted studies in which some healthy volunteers taking SSRIs developed suicidal thoughts. Drugs to be included in the review include paroxetine (Seroxat), citalopram (Cipramil), sertraline (Lustral), fluoxetine (Prozac) and fluvoxamine (Faverin). www.mca.gov.uk/aboutagency/regframework/csm/csmhome.htm
Intramuscular Zyprexa reaches Europe
30 June 2001
An intramuscular formulation of Eli Lilly's olanzapine (IM Zyprexa) has been approved in the EC for the treatment of agitation and disturbed behaviour in people with schizophrenia. The product is the first injectable atypical antipsychotic to become widely available in Europe. An injectable formulation of Pfizer's ziprasidone is approved in Sweden, but mutual recognition procedures enabling the product's approval in other countries have been delayed. Rapid-action intramuscular antipsychotics are used when oral agents would be too slow, and in cases of non-compliance. According to Eli Lilly & Co, studies show the injectable to be as effective as an intramuscular formulation of haloperidol, with fewer adverse effects. www.lilly.com
New treatment shows promise for Alzheimer's
30 June 2001
An orally active drug that may reverse Alzheimer's disease pathology is in phase II clinical trials with results expected next year. Clioquinol, a compound in development by Prana Biotechnology, has been reported to reduce the accumulation of beta-amyloid peptide in mice. The drug - which acts by binding copper and zinc - is the first such compound to be tested in human Alzheimer's disease. Its novel mechanism may help scientists better understand the processes leading to Alzheimer's - zinc and copper are thought to be involved in the cellular processing of amyloid proteins. Current therapies such as cholinesterase inhibitors can slow cognitive decline, but do not reverse or 'cure' Alzheimer's. www.pranabio.com
Rivastigmine and donepezil to go head-to-head
30 June 2001
Novartis Pharmaceuticals has announced that it is to conduct the first large-scale double blind trial comparing the efficacy of rivastigmine (Exelon) and donepezil (Aricept) for the treatment of Alzheimer's disease. The study, known as EXCEED (EXelon Comparison of Efficacy vErsus Donepezil), is designed to test whether the dual action of rivastigmine, which inhibits both acetylcholinesterase and butyrylcholinesterase, confers greater clinical benefit than donepezil, which acts only on acetylcholinesterase. The two drugs are the most commonly used treatments for Alzheimer's disease. www.novartis.com
Galantamine effective in vascular dementia
30 June 2001
Data presented to the World Congress of Neurology suggests galantamine (Janssen-Cilag's Reminyl) is effective for treating vascular dementia (dementia with cerebrovascular disease). In a six-month placebo controlled trial, galantamine - the first drug to show efficacy in this type of dementia - showed sustained improvement on the ADAS-cog scale in people with vascular or mixed dementia. Extending the study under a six-month open label protocol, all participants received galantamine (24mg). Those initially taking placebo also showed benefits on the ADAS-cog following the switch to the active drug. Janssen plans to file its product for vascular dementia pending the completion of further trials. www.janssen-cilag.com
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