Showing posts with label Biogen. Show all posts
Showing posts with label Biogen. Show all posts

Four reasons why approving the new Alzheimer's drug was a disaster

A few months ago, the FDA approved a new drug, aducamumab, to treat Alzheimer’s disease. This was the first time in 20 years that the FDA approved a drug for Alzheimer’s, and while that may sound hopeful, many experts have already pointed out that it was a colossal mistake, and a looming tragedy for Alzheimer’s patients. Here are 4 reasons why the approval of aducamumab (also called Aduhelm) is such a disaster.

1. The new drug just doesn’t work. The biggest problem is that Aduhelm doesn’t slow down or reverse the progress of Alzheimer’s. More than a year ago, I wrote about the failure of two trials of aducamumab. The two trials, designed to be identical to one another, were halted in March 2019 by the drugmaker, Biogen, due to a “futility analysis” that showed it just wasn’t working.

In other words, there was no point in continuing the trials. So Biogen halted them.

But then Biogen tried to rescue the drug. In what can only be described as torturing the data to try to find a result that they really, really wanted, they went back and looked at a subset of patients in one of the two trials, called EMERGE, and claimed that the higher-dose patients actually did get a benefit.

But the patients didn’t benefit. All that Biogen could argue was that some patients had lower levels of amyloid plaques in their brains. An independent group of scientists also looked again at Biogen’s data, and published a report saying that their analysis still didn’t support any benefit for patients.

It’s true that plaques do indeed accumulate in the brains of Alzheimer’s patients, and aducamumab does seem to reduce plaques. However, despite 30 years of research, no one has been able to show that reducing these plaques has any effect on the progress of the disease.

More to the point, the two trials run by Biogen, which measured clinical signs of disease, found that aducamumab didn’t affect the patient’s illnesses. It didn’t slow down or reverse the inevitable course of Alzheimer’s disease.

The FDA’s own outside panel of experts evaluated the evidence and strongly rejected aducamumab. (10 of 11 voted to reject it, and one panelist was uncertain.) The panel found that not only was there no clinical benefit, there was also a significant risk of harm, including dangerous swelling in the brain. About one-third of patients experienced these risks, and 10% of patients had to stop treatment because of adverse side effects.

And yet in July of 2021, in a nearly unprecedented action, the FDA approved the new drug. Three of the committee members resigned in protest.

Somehow, Biogen convinced the FDA to approve aducamumab based on the drug’s effect on a surrogate endpoint: the level of amyloid plaque in the brain. One could argue that this is similar to approving statins based on their effect on cholesterol levels: by reducing cholesterol, we can reduce the risk of heart disease. The analogy might be apt, but there’s a huge difference: we have data showing that lowering cholesterol does indeed reduce the risk of heart disease. In contrast, despite decades of study, we still don’t have any data showing that reducing the levels of amyloid plaques slows down or reverses Alzheimer’s.

2. A failed hypothesis. This leads to the second reason why the FDA’s action is such a disaster. For 30 years now, the Alzheimer’s community has pursued the “amyloid hypothesis,” which asserts that the buildup of amyloid plaques in the brain is the primary cause of Alzheimer’s. This was considered a huge breakthrough when John Hardy first proposed it back in 1991, and hundreds (perhaps thousands) of papers have been published since that time, exploring this hypothesis.

Over 100 drugs have been developed and tested for their ability to reduce plaques, and some of them (like aducamumab) do indeed reduce plaque levels. Unfortunately, none of them slowed down the course of the disease, so they never obtained FDA approval.

After 30 years of effort, it’s clearly time to recognize that the amyloid hypothesis is a failure. And yet the Alzheimer’s research community continues to cling to it, despite all the evidence that targeting plaques simply doesn’t work to treat the disease.

The FDA’s approval, over the objection of its own experts and a big outcry from the biomedical research community, will only breathe new life into this failed hypothesis. Even more unfortunate is that, by approving a treatment based on a surrogate endpoint, the FDA is now encouraging drugmakers to keep focusing on plaques, which will starve any efforts to find other causes–and other potential treatments–for this devastating disease.

This leads me to the third reason why the FDA’s approval of aducamumab is a disaster.

3. Greed wins. Why did Biogen work so hard to find some shred of evidence that they could use to convince the FDA to approve their new drug? The answer can be found in the price that Biogen set for the drug: $56,000 per year. As the editors of JAMA Internal Medicine have pointed out, if even one-sixth of Alzheimer’s patients in the U.S. alone were to take this drug, the annual cost would be $57 billion, which is far greater than the cost of all Medicare part B drugs combined in 2018.

In other words, aducamumab’s costs could bankrupt Medicare. Or to put it another way, Biogen doesn’t seem to care if Medicare goes bankrupt, as long as they can grab some massive profits.

What is still mysterious is why the FDA decided to overrule its own advisors. The FDA’s defense seems to be that they will require Biogen to continue collecting data “to verify the drug’s clinical benefit.” But they are giving Biogen 8 years to collect this data. That’s 8 years during which Biogen will reap massive profits, Medicare might collapse under the strain, and Alzheimer’s patients will continue to suffer.

In October, the FDA announced an investigation of its own approval process for Aduhelm. This seems rather bizarre: if the FDA suspects there was “improper contact” between Biogen and its own internal staff, then it should simply withdraw approval for the drug until the investigation is complete.

4. This whole affair is taking cruel advantage of a vulnerable, desperate group of patients. Finally, perhaps the worst aspect of this whole fiasco is how cruel it is to Alzheimer’s patients. As Dr. Jason Karlawish explained in JAMA Neurology, even though he disagrees with the FDA’s decision to approve this drug:

I must preserve and protect each patients’ autonomy. One way I do this is by being teacher to patients and their caregivers so they can make choices about how to live well with this disease. I cannot deny them the choices the health care system gives them. Aducanumab is now a choice.

Karlawish goes on to write that he will explain to patients that the benefits are uncertain, and the risks of brain swelling and other bad side effects are very real. But if the patients choose to try it, he will reluctantly prescribe Aduhelm.

We don’t have any effective treatment for Alzheimer’s, and it is a devastating illness. Patients and their families are likely to be desperate, and the mere fact of FDA approval will give them hope. I’ve no doubt that many will want to try Aduhelm, despite the risks. Giving them false hope is simply cruel.

And don’t forget that Biogen halted its own trials of Aduhelm due to “futility.”

The FDA made a huge mistake in overruling its expert panel and approving an Alzheimer’s drug that just doesn’t seem to work, that is outrageously costly, and that might cause serious harm to some patients. Let’s hope that this decision can be reversed. The world needs a safe and effective treatment for Alzheimer’s, and for now, we simply don’t have one.

New Alzheimer's disease treatment fails, then works, then fails again


 Alzheimer’s disease is one of the most devastating conditions of old age. By recent estimates, more than 5 million people in the U.S. have Alzheimer’s, and managing the disease will cost over $300 billion in 2020. As the population ages, this problem is growing worse, and yet we still have no effective treatment.

You might have seen rosy-looking ads for Alzheimer’s treatments, but nothing really works, not yet at least. That’s why many people were excited about the possibilities of a new drug, aducanumab, that showed early signs of being able to reduce the accumulations of “plaques” in the brain.

Background: in people with Alzheimer’s, a protein called beta-amyloid accumulates in the brain, forming plaques that seem to disrupt brain function. (This hypothesis is not fully proven, but it is widely considered credible.) Thus one way that we might treat Alzheimer’s would be to reduce or eliminate beta-amyloid plaques. That’s what Biogen’s new drug, aducanumab, is intended to do.

Biogen has run two separate trials, called “EMERGE” and “ENGAGE,” to test whether or not aducanumab (ADU for short) worked.

Here’s where things get murky. Back in March of 2019, both trials were halted due to “futility,” because ENGAGE was showing no benefits for the new drug. In EMERGE, the high-dose patients seemed to be getting some benefit, but Biogen had specified ahead of time that if either trial was failing, that would mean the drug wasn’t working. Thus they halted the trials, disappointing as it was.

Fast forward to October of 2019, though, and Biogen had a new story. They went back and looked at a subset of the patients in ENGAGE (the study that had failed), and said that there was a benefit after all, if they looked only at the high-dose patients. This past July, Biogen went to the FDA and applied for approval for ADU.

Just this past week, two very conflicting announcements about ADU appeared. First, on Wednesday, the FDA’s internal scientists released a very rosy report, saying that the data from one of the trials were “robust and exceptionally persuasive.” For the second trial, the scientists said that even though the drug initially seemed to fail, a closer review led them to conclude that overall, ADU did provide a benefit.

Biogen shares rose 45% that day, adding $17 billion to the company’s value.

Then on Friday, a panel of independent, external scientists released their conclusions, which resoundingly rejected the drug. The external panel said that the data from the two trials was unconvincing, and they pointed out “multiple red flags” in the analysis.

(Trading in Biogen stock was halted during the Friday meeting, but at the end of the day it was close to the high it reached on Wednesday.)

So what happened? It appears to be a classic case of cherry-picking: when the data from the ENGAGE study didn’t pan out, the company re-analyzed a subset of the data and found a more-positive picture.

That’s not really kosher, as explained by a separate group of scientists in a paper published just a few days ago in the journal Alzheimer’s & Dementia. In this paper, David Knopman and colleagues, from the Mayo Clinic and Stanford Medical School, analyzed data that Biogen has released from its two trials. (The trials haven’t been published, but some of the findings were released in a publicly-available slide presentation that the authors relied upon.)

Knopman and colleagues explained that after two conflicting trials, there simply isn’t enough evidence that ADU works, and they also offer alternative explanations for the positive findings. They argue that the best Biogen can do is to “perform another trial of high‐dose ADU of at least 78‐weeks duration,” which could determine whether or not the positive results were real or just coincidence.

It’s somewhat mysterious that the FDA’s internal panel released their rosy report about ADU on Wednesday, only to be slapped down just two days later by an independent outside panel of scientists. After reading the negative views of the external panel and the analysis in the paper by Knopman and colleagues, I’m very skeptical that ADU has any clinically significant effect. If it had a truly robust effect, it simply wouldn’t be so hard to tease it out.

So we still don’t have a good treatment for Alzheimer’s, but the world still needs one.