DefinedHealth

CNS has been crowned the most expensive therapeutic category, with an average per-drug development cost of $527 million, according to a 2004 Tufts report. Attrition in development of drugs for neurodegenerative conditions is a prime contributor, with few success stories and a long list of failures (Adis R&D Insight lists over 800 drugs for neurodegenerative disease being either suspended or discontinued). Like moths to a flame, though, pharma can’t help but go after this huge potential market—Alzheimer’s disease (AD) alone represents approximately 4.7 million patients in the US with estimates ranging from 11 million to 16 million by 2050.

While there have been successes in the clinic for drugs targeting neurodegenerative disease, by big pharma standards these have, for the most part, evolved into commercial failures. With the exception of Aricept (Pfizer), the first tolerable treatment for AD, and successful biologicals for the treatment of multiple sclerosis, products for neurodegenerative diseases have not broken the $300 million mark. Unlike other therapeutic areas such as cancer, where a meaningful benefit can be measured in a few months’ extension of survival time, the slow, progressive nature of neurodegenerative disease leaves little room for another drug that makes only an incremental improvement. The future neurodegeneration market will likely reward only those drugs that provide a significant improvement over current standard of care, meaning a slowing down, or even reversal of the disease process that will allow the patient to maintain activities of daily living.

Today there are over 200 drugs in clinical development for one or more neurodegenerative diseases and over 400 more in pre-clinical development. Are these drugs headed for the same market fizzle, or worse, flop, as their predecessors? Clearly, it serves nobody’s interest to abandon pursuit of medicines that address these devastating diseases. From a risk-adjusted standpoint, though, does investment in a fledgling neurodegeneration franchise (or a drug targeting a neurodegenerative disease) make good business sense for pharma or biotech? With regard to pharma in particular, is it more fiscally responsible given today’s market conditions to put conventional development of drugs for neurodegenerative disorders on hold until the science catches up, or is the path forward a navigational adjustment of some sort?