GlaxoSmithKline (GSK) have shown faith in EPIX Pharmaceuticals' G-protein coupled receptor (GPCR) drug development programme by agreeing to a collaboration which could cost up to $1.2bn (€900m), despite the fact that EPIX's most advanced drug candidate is only in Phase II trials.
GPCRs are the largest known class of drug targets with proven therapeutic benefits. Drugs that interact with these proteins make up nearly 40 per cent of the top 50 selling drugs worldwide. The proteins are responsible for responding to signals outside the cell and translating this into biological processes inside the cell.
In Alzheimer's disease, the build up of amyloid plaques in the brain can lead to nerve cell death. The resulting reduction in levels of a neurotransmitter called acetylcholine (ACh) is one of the main contributors to the dementia symptoms characteristic of the disease.
EPIX have been examining a specific GPCR called 5HT4. Their lead drug candidate, PRX-03140, aims to stimulate this protein, which could lead to increased levels of Ach. The drug could also stimulate the alpha-secretase pathway that prevents more amyloid plaques from forming and therefore slows the progression of the disease. PRX-03140 is currently in Phase II clinical trials.
EPIX will initially receive $35m for the discovery and development of drugs targeting four GPCRs up to clinical proof of concept. At this point, GSK will have an exclusive license option but will pay double-figure royalties on sales to EPIX. How much money EPIX will ultimately receive depends on the success of the partnership.
"This alliance will provide us with access to significant capital in the near and long term to support the ongoing development of PRX-03140 and three additional programmess, as well as the ability to continue to move forward our existing programmess. Furthermore, the co-promotion option in this collaboration provides further opportunity for EPIX to build a sales force in the future," said Michael Kauffman, chief executive of EPIX.
The collaboration will be conducted through GSKs Center of Excellence For External Drug Discovery (CEEDD).
"We are very excited to be working with the EPIX team both on the existing 5HT4 programme in Alzheimer's disease, a key disease area for GSK, and on other GPCR programmes which will be initiated as part of this collaboration," said Maxine Gowen, head of CEEDD.
The collaboration could become a very good deal if successful drugs against all four GCCR targets are found. Indeed, a spokesperson for GSK, pointed out to DrugResearcher.com, "the market potential for just one asset is quite significant."
The cost of deals like this have increased in price over recent years though.
She said: "The cost is rising in general but especially for late stage [drugs], because there are fewer and fewer drugs are out there."
She puts this down to a boom in licensing deals coupled with a 'low-hanging fruit scenario' where the easier targets have been extensively researched, leaving scientists to look both for alternative targets or a different way of approaching the same disease profile.