Research The LAX-101 Research Project in Huntington's disease Summary of Conference Presentation by David Horrobin October 2000

From HDA Newsletter UK Issue 58 Winter 2000

For the past six years Laxdale, a research company based in Stirling in Scotland, has been developing a new approach to the management of nervous system diseases including Huntington's disease in collaboration with Professor Krishna Vaddadi of Monash University in Melbourne, Australia. Dr Marina Lynch of Trinity College, Dublin has also been involved in some of the basic scientific studies. LAX-101 is the product of this research programme.

To date three main studies specifically on Huntington's disease have been carried out. Professor Vaddadi has carried out an animal study on mice carrying the human Huntington's disease gene and also a human placebo-controlled trial in seventeen patients who were in the mid-stage of the illness. Dr Basant Puri, of the Hammersmith Hospital in London, has carried out a placebo-controlled trial in seven patients who were hospitalised and requiring 24 hour care.

Professor Vaddadi, working with John Drago, Jerry Clifford and John Waddington, found that when a formulation containing LAX-101 was given to the mice from birth it prevented the development of the movement disorders which in these animals usually appear at 30-40 weeks of age. Both of the clinical studies in Australia and in London showed that in the placebo (dummy treatment) groups a majority of patients deteriorated during the course of the study whereas in the actively treated groups a majority of patients showed improvement. Success was by no means certain since a few patients in the placebo groups stayed unchanged or improved while a few patients in the LAX-101 group deteriorated.

However, these results are encouraging and as a result Laxdale is setting up a major placebo-controlled trial in over 120 patients which should provide a definitive answer as to whether LAX-101 is or is not helpful in Huntington's disease. Many people are concerned about the ethical issues involved in placebo-controlled trials. However such trials are absolutely required by the European Medicines Evaluation Agency (EMEA) and by the Food and Drug Administration (FDA) in the USA. Without placebo-controlled trials these agencies will simply not allow any medicine to be made available to patients in either Europe or the USA. In order to ensure that a treatment which is effective is made available on the NHS, such trials are therefore an absolute necessity. Laxdale very much understands the concerns of the Huntington's disease community and is therefore trying to complete the studies as quickly as possible. If the trials are successful then Laxdale will immediately apply to the EMEA and to the FDA for permission to make available LAX-101 to patients.

The trial is being conducted at four sites, the Hammersmith Hospital in London, Johns Hopkins Hospital and Emory University in the USA and the University of British Columbia in Vancouver, Canada. In addition Professor Vaddadi in Melbourne will be continuing with his research programme in collaboration with Laxdale. The multicentre study should start in about mid-November after the ethical committees in the relevant institutions have all given their approval. The trial will mainly involve patients who are living at home but can still travel to hospital for examination. It will last for one year and will involve six visits, first to assess whether someone is suitable for the trial, then for full examinations at the start of treatment, after six months and after 12 months, and for minor investigations at 3 months and 9 months. Because fish oil may interfere with the evaluation of LAX-101, patients who are taking fish oil or who have been taking fish oil in the past three months will not be eligible for the study. There will be no charges to patients for any of the investigations and reasonable travel expenses will be reimbursed. All patients in the study will be offered LAX-101 at the end of the study. If LAX-101 is shown to work, it will be provided free of charge to the participants until such time as it becomes available as a medicine in each country. The Huntington's Disease Associations in the various countries will be working with Laxdale to help recruit appropriate patients for the study.

Laxdale understands the problems and frustrations involved in waiting for an outcome but we will do everything that is humanly possible to get the results quickly. We expect that the last patients will be recruited by mid-2001 and therefore will complete the 12 months by mid-2002. We expect to have the results by the autumn of 2002. If LAX-101 works it should be generally available after approval by the EMEA and FDA some time in the first half of 2003.

>From HDA Newsletter UK Issue 58 Winter 2000