Staggeringly few Alzheimer's disease medications survive clinical trials. But with the market expected to triple before 2020, Big Pharma keeps lining up for the pipeline slaughter. This year started with an expected failure from Medivation (MDVN +0.00%) and Pfizer (PFE 0.74%) that ended their collaboration.
But the two highest-profile project failures came from Eli Lilly (LLY +0.42%) and the team of Pfizer (PFE 0.74%) and Johnson & Johnson (JNJ +0.02%). Those missteps cast doubt on a long-held treatment theory that Merck (MRK +1.29%) is still pursuing. Does Merck have a chance of succeeding?
First to fall
The first defeat of 2012 came with the January announcement that Pfizer and Medivation would cancel further Dimebon trials after flunking another late-stage round. The antihistamine had long since lost investor confidence because of previous trial disappointments. But this was the failure that finally sent Pfizer running from the collaboration. That meant writing off more than $700 million in upfront and milestone payments.
Medivation turned its focus to a promising prostate cancer drug that later received Food and Drug Administration approval. Pfizer next appeared in one of the two most-watched drug disappointments of the year.
Two peas in a (faulty) pod
Bapineuzumab from Johnson-Pfizer and solanezumab from Lilly were often mentioned in the same breath because of their similarities. Both target the plaques of beta amyloid peptides that are linked to Alzheimer's. There were lackluster midstage and late-stage trials featuring patients with mild to moderate Alzheimer's.
And both drugs failed their phase 3 trials.
Johnson-Pfizer cancelled bapineuzumab in August after its phase 3 trial missed both endpoints. Johnson expected to take as much as a $400 million charge, but Pfizer didn't take a charge.
Lilly's solanezumab fared better. Phase 3 trials failed endpoints but showed surprising evidence of improving mild forms of the disease. Lilly withdrew the drug from the Food and Drug Administration filling process, with plans to circle back for new phase 3 trials focusing on patients in earlier stages.
The consensus seems to be shifting toward treating milder cases. And that makes it even stranger that Merck is continuing with its own drug trial using mild to moderate Alzheimer's patients.
A new hope?
Merck is raising eyebrows by continuing with a beta amyloid-related project with a mild-to-moderate patient base. The company recently initiated phase 2/3 studies on MK-8931, which inhibits the enzyme that promotes beta amyloid peptides.
Phase 1 trial results showed more than a 90% reduction in beta amyloid in the spinal fluid of healthy patients. The drug was well tolerated during those trials, with minimal side effects. But the results for moderate stage disease might turn out differently.
Merck's hoping to avoid the previous patient problems by using General Electric's investigational imaging agent for screening. The agent will test the amounts of beta amyloid present in the brain to find those who have the best chance of benefiting from MK-8931.
Foolish final thoughts
The Alzheimer's pipelines do expand beyond the beta amyloid drugs. There are preventive treatments and hormone therapies in trials. But the beta amyloid theory stems from a long-held belief that slowing or reducing the plaque could treat Alzheimer's. Now comes the turning point for the hypothesis. Merck's success would make the biggest waves, since that would include the elusive moderate patients.
The Big Pharma companies involved in Alzheimer's treatments won't see their share prices suffer much from these failures. Their portfolios are too diverse for one failure to produce a drastic fall. But approval in this sector would create significant revenue opportunities.
