Juvmo (tavapadon) Approval

A new drug for Parkinson’s was approved this week by the FDA. What does this mean for you – a person with PD and your doctors?

When I want to understand the impact of a therapy, I rely on three sources of information: 1. Its peer-reviewed clinical trials, 2. the FDA’s review documents and 3. the FDA-approved product label.

I wrote last month about my review of the clinical trials for tavapadon, which made me expect this drug would soon be approved. With this week’s announcement, we now can learn from its product label, so two of my sources are available.  But the FDA’s review documents are not yet public. Only the approval letter is available so far, but not the detailed review files. That means that although we know the drug works, we don’t know how it fits into an overall treatment plan.

Should the drug be used as the first therapeutic used for treating people with Parkinson’s? Should people on another dopamine agonist be switched to tavapadon (and if so, how to manage the transition).

We won’t know the answers to such questions because the only way to know is when a clinical trial is completed that compares different treatment strategies. This is why I advocated for requiring the drug to be subjected to the standard scientific approach for any new drug, a randomized, double-blind, clinical trial comparing this dopamine agonist (with its unique pharmacologic characteristics) to those already available.

But even without such a trial, we can start to prioritize treatments with the insights possible from the FDA’s detailed review of the data. Hopefully those files are released soon.

What does Tavapadon do for people with PD?

We know it’s useful, but I simply can’t tell what benefit a person should expect from using the drug. Reading the FDA-approved label; it’s easy to learn what could go wrong (with listings of contraindications, warnings/precautions, adverse reactions, drug interactions), but there isn’t information to tell me what people should expect as benefits.

To measure the effect of a drug on PD the MDS-UPDRS Part II score is used.  The score is based on the person’s response to 13 issues affected by PD – listed here:

1. Speech
2. Saliva and drooling
3. Chewing and swallowing
4. Eating tasks (cut food, handle utensils)
5. Dressing (button, zip, put on arms)
6. Hygiene (wash, brush teeth, use comb)
7. Handwriting
8. Doing hobbies and other activities
9. Turning in bed
10. Tremor (shaking of any part of the body)
11. Getting out of bed, a car, or a deep chair
12. Walking and balance
13. Freezing

It’s important to understand whether the effects of the drug are primarily on some but not all the 13 issues, and how the benefits and the side effects appear to compare with other dopamine agonists. (Note that only a direct comparison in a trial will allow us to know how different drugs compare but having the detailed data provides useful insights to help prioritize between the different drugs.) This information has not been disclosed by the tavapadon investigators; not an unusual situation this soon after the completion of the trial. It takes a long time to complete the analyses, write up the research and then publish it. But I do expect to have access to the FDA review documents to understand more fully the effects of the drug. 

My Skepticism

I believe complete transparency is necessary to understand how to integrate and prioritize use of a new drug within clinical practice. So far, the lack of transparent disclosure by the FDA is a problem, and until the review files are available for review, it is not possible to know when physicians should prescribe the drug or when a person with PD should take the drug.

With the approval and launch of this new drug, the FDA’s obligation is to provide the documents supporting its approval which also allows us to understand how to use the drug optimally. I don’t want to sound skeptical or overly critical – but both perspectives are appropriate when reviewing the data for use of any new drug.