Alzheimer’s drug slows progression of disease in trial

Makiko Kitamura
Bloomberg News

Biogen Idec Inc.’s experimental drug for Alzheimer’s slowed progression of the disease in a study, offering a glimmer of hope after a string of failures by competitors who have tackled the ailment.

In an early-stage trial of 166 patients, Biogen’s drug BIIB037 reduced beta amyloid in the brain and also reduced cognitive decline, with higher doses and longer treatment resulting in more improvements. Beta amyloid, a protein fragment that creates plaque in the brain, was observed with PET scans. Cognition was measured with tests used by neurologists, including one the Food and Drug Administration may use to assess the drug for approval.

“Either result alone would have been exciting, but to see them both in the same study makes it even more exciting,” said Alfred Sandrock, Biogen’s chief medical officer. The results are positive enough that Biogen is skipping midstage testing and moving directly into final-stage trials that will begin later this year, Sandrock said.

The company is pushing rapidly ahead into an area where other drugmakers have tried and fell short in final-stage trials. The medications solanezumab, from Eli Lilly & Co., and bapineuzumab, developed by Pfizer Inc., Johnson & Johnson and Elan Corp., both failed to show a significant effect on the disease in trials. Lilly is currently retesting solanezumab in earlier-stage patients, while bapineuzumab has been scrapped.

“We are excited about it,” said Keith Fargo, director of scientific programs and outreach at the Alzheimer’s Association, a Chicago-based nonprofit advocacy group. “We have to do the big phase 3 study to see if it’s actually going to work. There have been a lot of promising phase 1 and phase 2 trials that didn’t work out.”

Investor anticipation

Biogen shares have climbed 41 percent since the company reported preliminary findings from the BIIB037 trial in December. Investors have awaited the full trial results to gauge whether they back up the initial optimism over the drug’s chances for success. Biogen Chief Executive Officer George Scangos told investors at the Cowen Group Health Care Conference in early March that management was “quite excited” about the data and that late-stage trials should start later this year.

The trial may have avoided pitfalls that tripped up other drugmakers because it focused on patients in the early stage of Alzheimer’s disease, made sure they had beta amyloid in the brain and verified they had Alzheimer’s and not a different form of cognitive impairment, Sandrock said.

After a year at the highest dose of treatment, the PET scans showed that plaque was reduced to a level that was “very close to the upper limit of normal,” he said. At the lowest dose, the reduction wasn’t statistically significant.

Side effects

On cognition, using a test called the Mini Mental State Examination, patients in the placebo group worsened by an average of 3.14 points after one year, compared with 2.21 points among patients who took the lowest dose and 0.58 in the highest dose.

The drug had side effects, particularly at the highest doses. Brain scans showed a number of patients abnormalities that have been seen with other experimental Alzheimer’s drugs. And 22 percent of those who took the drug had headaches, versus 5 percent on a placebo.

Alzheimer’s is the most common form of dementia, affecting more than 5 million Americans, according to the Alzheimer’s Association. The disease, which is progressive, causes symptoms including memory loss, confusion, and behavior changes. There is no approved cure for Alzheimer’s.

Biogen is best known for its multiple sclerosis drug Tecfidera, which brought in $2.9 billion in sales last year. The company bought BIIB037, or aducanumab, from Neurimmune Therapeutics in 2007.

“You can never be certain in this industry,” Sandrock said. “But we feel confident enough in the data that we’ve seen that it’s a good investment to make to move forward aggressively into phase 3.”