Drug Development Process

In Dr. Michael Decker’s talk on drug discovery and development, he described to us the difficulties that are associated with the drug discovery process. He discussed with us Richard C. Mohs and Nigel H Greig’s article, “Drug discovery and development: Role of basic biological research,” which highlighted the complexity of drug development. On average, the process lasts 13.5 or more years costing over a billion dollars. Mohs and Grieg point to some of the issues Alzheimer’s disease deals which help explain why there is such high failure rates. Decker strongly expresses this by explaining how exhausting and laborious the process of development is in order to reach FDA approval. Beginning with the identification of a candidate molecule, the probability that a new valid biological target will be identified is extremely low. This is seen in Alzheimer’s disease. According to Mohs and Grieg, central nervous system drugs have higher failure rates and take more time to develop. On record, 100% of the attempts of trying to develop a neuropsychiatric drug for Alzheimer’s disease has failed. Drugs, such as Aducanumab, have made it past preclinical trials, and into clinical development to only be disapproved. A failure this late in development is an extremely costly investment and time consuming.

Just recently, the development of Aducanumab, which is a drug meant to treat Alzheimer’s disease, came to a halt. In Ned Pagliarulo’s article, “Aducanumab’s failure puts pressure on the field to look beyond amyloid,” he talks about the difficulties of researching amyloid plaques and how aducanumab comes up short in the drug development process. For over a decade, Biogen, which is a major biotechnological company focused on defeating devastating neurological diseases, had invested over $743 million in developing aducanumab. This is because it was “judged unlikely aducanumab would meet its goal of slowing cognitive and functional impairment in patients with mild cognitive impairment or dementia due to Alzheimer’s disease” (Pagliarulo 2). Evidence showed that aducanumab was able to significantly reduce the amount of amyloid plaque. Where aducanumab fell short, was in Phase 3 of clinical trial testing when there was insufficient evidence regarding the efficiency of aducanumab. It did not have to do with the safety of the drug. Phase 3 was expected to be finished in 2022. Even though there have been repeated failures with trying to treat Alzheimer’s disease, aducanumab showed compelling results that support that the amyloid hypothesis is still credible. This example of Biogen’s experiences with developing aducanumab exemplifies Decker’s discussion about difficulty in completing the drug development process. It is a very long and money-consuming process that more than not ends in failure. The future still remains uncertain for Alzheimer’s disease and the development of a therapeutic drug.

On September 7, 

Mohs, R. C., & Greig, N. H. (2017). Drug discovery and development: Role of basic biological

research. Alzheimer’s & Dementia: Translational Research & Clinical Interventions

Pagliarulo, Ned. “Aducanumab's Failure Puts Pressure on Field to Look beyond Amyloid.” ‘        BioPharma Dive, 22 Mar. 2019, https://www.biopharmadive.com/news/aducanumabs-

failure-puts-pressure-on-field-to-look-beyond-amyloid/551071/.