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>http://www.parkinsonsdisease.com/index.htm >Latest progress in Parkinson's disease > >The latest data on foetal neurotransplants, new apomorphine delivery >systems and new drugs in clinical >and preclinical trials were reported at the 7th International Symposium on >Parkinson's Disease in London on March 23rd-26th. > >Foetal neurotransplantation >Academics from several institutions reported continuing success with >transplanting human foetal neurones into the brains of Parkinson's patients, >and discussed possible future directions of this approach. > >Around 200 patients have received such therapy. It is now well established >that graft survival, re-innervation and >dopamine production can be achieved. The clinical benefits, which take >several months to become apparent, >include improved fine motor functions and speech, and prolongation of the >effects of levodopa, the current >mainstay of treatment for Parkinson's. Patients also experience reduced >rigidity and akinesias, levodopa-induced >dyskinesias and "off time" (periods when patients experience sudden >worsening of symptom control). These >effects have lasted for more than seven years in some patients. > >Results have been variable, however, probably because of the differences in >the patients' disease states and the >surgical techniques used. Recovery is rarely complete, and there may be >functional deterioration over time >(despite long-term graft survival); this is thought to be due to disease >progression counteracting the transplant's >effects. > >Speakers discussed several ways to improve the technique. These included >the use of neurotrophic factors to >increase graft survival and outgrowth, and to increase the number of grafts >and situate them in different parts of >the brain. > >Dr C Olanow of Mount Sinai Medical Center, New York, is currently >conducting a double-blind 36-patient >Phase III trial of the procedure. Results will be available in 1999. > >Diacrin and Genzyme, which are conducting Phase I trials using neurones >from pig embryos (Neurocell-PD), >did not present any results at the conference. > >New apomorphine delivery systems >Speakers discussed several new delivery systems for the dopamine agonist, >apomorphine, currently used for >patients taking levodopa who experience "wearing off" of symptom control >between doses. (Britannia, for >instance, launched Britaject, a prefilled multidose injector pen, in the UK >last October.). > >Dr Richard Dewey from the University of Texas reported on the nasal >delivery of apomorphine using an adapted >metered-dose inhaler. He said apomorphine was the treatment of choice as a >rescue agent for the sudden onset of >"off time", but that patients may prefer nasal delivery to self-injection. >Three of the nine subjects in this trial >withdrew due to severe nasal congestion, but the researcher thought that >only some patients would be susceptible >to this side-effect. > >Dr Teus van Laar from Leiden University, the Netherlands, announced >preliminary studies using Iomed's >transdermal iontophoretic patch system to deliver apomorphine. The drug is >pumped across the skin by a weak >battery-generated electric current. In the 10-patient study, the patch was >left on for one hour, and caused slight >skin erythema. Dr van Laar concluded that apomorphine levels would reach >clinical efficacy if the patch were >used for longer, and that the level of skin irritation may determine the >clinical usefulness of this technique. > >Amgen's GDNF >Preliminary results from Amgen's 50-patient Phase I trial of glial- >cell-derived neurotrophic factor (GDNF) are >expected towards the end of this year or the beginning of 1998, the company >reported. GDNF has been found to >upregulate dopamine production and have a neuroprotective effect in animal >studies. As GDNF cannot cross the >blood-brain barrier, the company is using an access port developed by >Medtronic, which allows once-monthly >administration directly into the brain. > >Kyowa Hakko's adenosine antagonist >The Japanese company, Kyowa Hakko, presented animal data on two adenosine >A2a antagonists, KW-6002 and >KF17837. Adenosine A2a receptors are localised to areas of the brain >implicated in Parkinson's and are thought >to be involved in motor symptoms and dyskinesias. > >The compounds reduced symptoms in several animal models of Parkinson's, and >the company told Scrip that it >plans Phase I trials with KW-6002. It also claimed that this compound has >"much higher potency and selectivity" >than Schering-Plough's adenosine A2a antagonist, Sch-58261, which is >reported to be in preclinical studies for >the treatment of neurological disorders. > >Source: Scrip. 9th April 1997 > > > >