A New Animal Model For Depression: Scientists Reveal First Drug-Test Results
Preliminary testing of new anti-depressant drugs has - to date - been done on human volunteers or in relatively unreliable animal models.
January 24, 2003
Victorian scientists - at the biotech company Autogen Limited - have developed and patented an animal model which, under controlled conditions, experiences the behavioural symptoms of depression.
Victorian scientists - at the biotech company Autogen Limited - have developed and patented an animal model which, under controlled conditions, experiences the behavioural symptoms of depression.
Results to be released next week at the Australian Neuroscience Society conference in Adelaide (Jan 28-31) will reveal the existence of an entirely novel animal model for the testing of anti-depressant drugs.
The model will allow pharmaceutical companies to rapidly and cheaply test potential anti-depression compounds.
More importantly, however, anti-depressant drugs will more reliably be trialed in animals, according to Professor Greg Collier, CEO of Autogen. "These results confirm that this animal model has potential application both in gene discovery research and as a rapid, cost-effective and reliable screen for therapeutic lead compounds," he said.
Autogen has applied for a patent to protect the use of this animal model for the preliminary screening of anti-depressants. The use of the model is expected to increase earnings of the company's growing fee-for-service eXpress Technology Platform.
The model gives Autogen a big advantage internationally in the discovery area and the hunt for new therapeutic targets for depression, according to Collier who has been discussing the potential of this model with a number of pharmaceutical companies to allow access to the model as a first screen for their anti-depressant compounds. "Using our animal model will allow pharmaceutical companies to relatively cheaply weed out those drugs which have no effect on the symptoms of depression while helping them focus on the drugs that have the potential to proceed to clinical trials," Collier said.
"This model will be useful for the pharmaceutical market which is looking to cut costs and speed up the process to developing the next Prozac."
The Research Results:
Researchers at Autogen and Deakin University have shown that when socially isolated the Israeli sand rat experiences symptoms normally associated with depression and anxiety, particularly a range of behavioural changes such as reduced grooming and a reduction in exploratory and ambulatory activity.
The model is seen as a good model for human behaviour (and the testing of drugs used in humans) because these rats - when separated from their litter mates - exhibit a range of behaviours that are consistent with the symptoms displayed by depressed and anxious humans.
When placed into an open area, the isolated animals remain near the perimeter rather than explore the more-exposed central parts of the trial space.
However when the isolated animals were treated with the minaprine they spent more time exploring the area and would willingly enter the middle of the trial space.
The pharmaceutical industry has clear guidelines concerning animal models for use in behavioural research. New models must demonstrate three attributes:
- face validity - in which animals show altered behaviour consistent with mental illness
- construct validity - in which there must be a logical and repeatable reason that explains the observed behaviour
- predictive validity - in which observed effects can be reduced by existing therapeutic intervention
The results to be presented at the Adelaide conference demonstrate that the Israeli Sand Rat, Psammomys obesus conforms to all of these guidelines.
Background on Depression and Anxiety:
- Depression affects up to 50% of the population at some time in their lives
- Depression affects all age groups
- It is considered a multi-factorial disease with genetic and environmental causes
- Anti-depressants are the world's highest selling drug class - world sales in 1997 of $15 billion (AUD) with sales expected this year to reach $30 billion (AUD)
| Professor Greg Collier: | 0419 897 501 |
Results to be released next week at the Australian Neuroscience Society conference in Adelaide (Jan 28-31) will reveal the existence of an entirely novel animal model for the testing of anti-depressant drugs.
The model will allow pharmaceutical companies to rapidly and cheaply test potential anti-depression compounds.
More importantly, however, anti-depressant drugs will more reliably be trialed in animals, according to Professor Greg Collier, CEO of Autogen. "These results confirm that this animal model has potential application both in gene discovery research and as a rapid, cost-effective and reliable screen for therapeutic lead compounds," he said.
Autogen has applied for a patent to protect the use of this animal model for the preliminary screening of anti-depressants. The use of the model is expected to increase earnings of the company's growing fee-for-service eXpress Technology Platform.
The model gives Autogen a big advantage internationally in the discovery area and the hunt for new therapeutic targets for depression, according to Collier who has been discussing the potential of this model with a number of pharmaceutical companies to allow access to the model as a first screen for their anti-depressant compounds. "Using our animal model will allow pharmaceutical companies to relatively cheaply weed out those drugs which have no effect on the symptoms of depression while helping them focus on the drugs that have the potential to proceed to clinical trials," Collier said.
"This model will be useful for the pharmaceutical market which is looking to cut costs and speed up the process to developing the next Prozac."
The Research Results:
Researchers at Autogen and Deakin University have shown that when socially isolated the Israeli sand rat experiences symptoms normally associated with depression and anxiety, particularly a range of behavioural changes such as reduced grooming and a reduction in exploratory and ambulatory activity.
The model is seen as a good model for human behaviour (and the testing of drugs used in humans) because these rats - when separated from their litter mates - exhibit a range of behaviours that are consistent with the symptoms displayed by depressed and anxious humans.
When placed into an open area, the isolated animals remain near the perimeter rather than explore the more-exposed central parts of the trial space.
However when the isolated animals were treated with the minaprine they spent more time exploring the area and would willingly enter the middle of the trial space.
The pharmaceutical industry has clear guidelines concerning animal models for use in behavioural research. New models must demonstrate three attributes:
- face validity - in which animals show altered behaviour consistent with mental illness
- construct validity - in which there must be a logical and repeatable reason that explains the observed behaviour
- predictive validity - in which observed effects can be reduced by existing therapeutic intervention
The results to be presented at the Adelaide conference demonstrate that the Israeli Sand Rat, Psammomys obesus conforms to all of these guidelines.
Background on Depression and Anxiety:
- Depression affects up to 50% of the population at some time in their lives
- Depression affects all age groups
- It is considered a multi-factorial disease with genetic and environmental causes
- Anti-depressants are the world's highest selling drug class - world sales in 1997 of $15 billion (AUD) with sales expected this year to reach $30 billion (AUD)
| Professor Greg Collier: | 0419 897 501 |
