BiotechDispatch recently spoke with Dr Darryle Schoepp, Vice President and Neuroscience Discovery Therapeutic Area Leader for MSD's global research organisation.
Dr Schoepp was in Australia to participate in a symposium in Adelaide on drug discovery and development for cognition and Alzheimer's disease.
The symposium was part of the company's collaboration with leading Australian biotechnology company, Bionomics.
Dr Schoepp addressed the symposium on challenges in the development of neuroscience therapies, including what has changed and where it is headed.
It is hard to imagine someone more qualified to comment on the subject given his almost three decades working in the area, including long stints at Lilly and now MSD.
"I truly loved my early days in research but now is the most promising time, and it really is important. Brain disease is significantly related to ageing - and we are living longer - because we all only get a certain number of neurons."
He says the work currently underway would not have been possible just 5-10 years ago because of biomarkers .
"We are now running a prevention trial for a molecule in Alzheimer's disease, something that would not have been possible without the development of biomarkers," Dr Schoepp told BiotechDispatch.
He says biomarkers have made an enormous difference because they have dramatically reduced the risk of failure and enabled companies to target their research.
"When you know what causes something you have a shot at fixing it. We know more about what is causing a disease, whereas before it was just a random shot that a molecule might work for a particular disease. "
He also points to other developments in science that have helped progress research into brain diseases.
"Neurodegenerative conditions are human diseases, so you can't model them in anything other than a human. The science is so much better now. We used to have to wait until someone had died and then section their brain. We can use imaging techniques now."
MSD is investing significant resources in neuroscience, a direction strongly and publicly backed by the company's CEO Kenneth Frazier, who argues the significant unmet medical need justifies investment in an area historically characterised by significant R&D failure.
"Ken has been very supportive of our research into Alzheimer's disease," said Dr Schoepp.
"He is supporting a large investment in late stage trials that could be revolutionary, and it's very important. Neurodegenerative conditions have a very high burden of illness. There is no treatment for some diseases, and there are no disease modiyfing agents," he adds.
MSD has several compounds in development, including verubecestat, an inhibitor of beta-site amyloid precursor protein cleaving enzyme 1 (BACE).
"The molecule is quite amazing in that it is like turning off the tap in a sink. We still have a lot of questions to answer, and as an area it's not for the faint-hearted because we are trying a lot of things that have not been tried before, but we have a lot of optimism that the hard work will pay off."
Dr Schoepp said finding patients is one of the great challenges with running trials in Alzheimer's disease.
"Because of the nature of the disease we screen four patients for every one person enrolled."
Another long-term challenge is the need to identify disease progression markers, with research now limited to identifying patients at risk of developing Alzheimer's disease.
"We can't tell them how much they are progressing," he said.
In relation to MSD's work with Bionomics, he says the company is "excellent" scientifically and a "great collaborator".
The two companies recently extended their original agreement signed in 2013 under which they are collaborating on the discovery and development of novel, small molecule drug candidates for the treatment of chronic and neuropathic pain utilising Bionomics’ ionX and MultiCore drug discovery platforms. MSD also acquired a US$9 million stake in Bionomics.