Recent studies based on cognitive tests and feedback from caregivers have shown the drug to be beneficial. Memantine, marketed under the brand names Namenda by Forest Laboratories, Axura by Merz, and Ebixa by Lundbeck is thought to have advantages over more established AD drugs such as Eisai and Pfizer’s Aricept and Novartis’ Exelon, which boost AChEI-related signaling. More clinical studies are required, though.
The current U.S. market for all these products is about $2.5 billion and growing at over 10% per year. The global market should reach $5 billion within a few years. Pharmaceutical audit data from Wolters Kluwer shows 2007 sales of $1.4 billion for Aricept, $705 million for Namenda, and $191 million for Exelon.
According to a 2007 Decision Resources report, this AChEI market is expected to eventually slow or decline as generics take over and new-generation products hit the market. This may take a few years, however. Frost and Sullivan forecasts the U.S. market to grow to about $4 billion by 2010 then briefly decline followed by renewed growth as disease-modifying drugs are introduced in 2011.
A MedaCorp and Leerink Swann & Co. White Paper states, “Treatment that could delay the onset of Alzheimer’s disease could reduce the number of patients by 50%, thus saving $50 billion in annual healthcare costs.”
Elan has a broad pipeline of products in clinical development in Phases I through III. Bill Tanner, Ph.D., of Leerink Swann has an Outperform rating on the firm. CSFB has also added Elan to its outperform list. Decision Resources projects that its lead candidate, bapineuzumab, will launch by 2011 with blockbuster potential of $5 billion by maturity if there are no safety issues.
Elan’s immunotherapies consist of an immunoconjugate in Phase II and two humanized mAbs. While one mAb is in preclinical development, bapineuzumab is in a pivotal Phase III trial. The study is using a new cognitive-function endpoint called NTB (neuropsychological test battery) instead of the ADAS-cog gold standard. Bapineuzumab is engineered to clear the neurotoxic beta-amyloid peptide, which accumulates in the brains of AD patients.
Elan is also developing beta and gamma secretase inhibitors with a Phase II product in a partnership with Eli Lilly. These enzyme inhibitors clip the amyloid precursor protein thus preventing the formation of amyloid plaques.
Another company faring well with some analysts is Epix Pharmaceuticals. Alan Carr of Needham and Co. has a Buy on Epix considering that the company has four mid-stage clinical programs and new drivers are expected over the next six months. RBC Capital also recently initiated an Outperform on the stock.
Epix Phase II portfolio consists of one AD candidate, while the other two target pulmonary hypertension and depression. The firm also has a Phase I AD candidate.
The mid-stage small molecule, 5HT-4, is a selective agonist of a specific GPCR. It is being evaluated in a Phase IIa trial as a single agent and in combination with Aricept. A Phase IIb trial is expected to begin by mid-year with partner GlaxoSmithKline. The mechanism of action is the stimulation of the alpha-secretase pathway and Ach production in the brain, which should improve cognition.