US approves tavapadon, a once-daily Parkinson's pill aimed at a different dopamine receptor, adding about an hour a day of good movement

Parkinson's disease kills the brain cells that make dopamine, the chemical messenger the brain uses to produce smooth, purposeful movement. By the time the shaking and stiffness show, most people have already lost 60 to 80 percent or more of those cells. The main treatment, levodopa, is a pill that nerve cells turn into dopamine. It works, but over the years each dose works for a shorter stretch and less predictably, and people come to spend part of every day in off time, the hours between doses when the medicine has worn off and the slowness and stiffness return.

On 25 September 2026 the US Food and Drug Administration approved a new pill for those people. Tavapadon, which AbbVie will sell as Juvmo, is taken once a day and belongs to a class of drugs called dopamine agonists, which do not replace the missing dopamine but imitate it, attaching to the docking sites on brain cells that dopamine uses, called receptors, and switching them on. In the trial that tested it alongside levodopa, people who added tavapadon gained 1.70 hours a day of good movement, against 0.60 hours for people who added a placebo, a difference of 1.10 hours.

The older dopamine agonists switch on receptors across several brain circuits at once, including those for reward and alertness, which is why they can bring daytime sleepiness, sudden sleep attacks, hallucinations and impulse control disorders, the hard-to-resist urges that lead to compulsive shopping, eating or sex. In the language of the trial report, those drugs act mainly on the D2 and D3 types of dopamine receptor. Tavapadon was designed to act on two others, D1 and D5, which the Michael J. Fox Foundation describes as targeting only the brain circuit for movement. That is the reason the drug exists: the hope is motor relief with fewer of the side effects that have limited the class.

How we know

The approval rests on a series of late-stage trials called TEMPO. The one for people already on levodopa, TEMPO-3, was published in JAMA Neurology in 2026. It was a randomised controlled trial, in which 507 adults with Parkinson's who were having fluctuations on a stable dose of levodopa were assigned by chance to add either tavapadon, at 5 to 15 milligrams once a day, or a matching placebo, with neither patients nor doctors knowing which, for 27 weeks. They were recruited at 148 sites in 14 countries between September 2020 and February 2024. They were 65 years old on average, had lived with the disease for 6.7 years, and were spending 5.5 hours of a typical day in off time.

The trial's main measure was the change in daily good on-time, the hours of good mobility without troublesome dyskinesia, the involuntary twisting and writhing movements that Parkinson's medicines themselves can cause. By week 26 that had risen by 1.70 hours in the tavapadon group and 0.60 hours in the placebo group. The 1.10 hour difference has a 95 percent confidence interval, the range the true figure very likely falls within, of 0.60 to 1.70 hours, and it was statistically significant, meaning unlikely to be down to chance. Off time fell by 1.88 hours a day with tavapadon against 0.93 hours with placebo, a difference of 0.94 hours.

Side effects were more common on the drug. In the trial's count of adverse events, any unwelcome change in health recorded during the study whether or not the drug caused it, 180 people on tavapadon, 71.7 percent, reported one, against 140 people, or 55.1 percent, on placebo. Most were mild to moderate, and 93.2 percent were not serious. The ones that reached at least 5 percent of people taking the drug were nausea (14.3 percent), dyskinesia (10.0 percent) and dizziness (7.6 percent). Across the TEMPO trials, the Michael J. Fox Foundation reports, impulse control disorders, daytime sleepiness and hallucinations seemed to occur less often than with older agonists, though hallucinations and a drop in blood pressure on standing were also seen in people with more advanced disease. The study was the manufacturer's: its lead author was paid by AbbVie as global principal investigator of the TEMPO studies, and several of its authors were AbbVie employees.

Why it matters

An hour a day sounds small. For someone spending 5.5 hours of each day with their symptoms back, the trial's 0.94 hour cut in off time is about a sixth of that lost time returned, and it comes from a single daily pill rather than another dose to time. The FDA lists Juvmo among the novel drugs it has approved in 2026, 45 of them by late September. The trial report calls it novel for a reason: the dopamine agonists available until now act mainly on the D2 and D3 receptors, and this one acts on D1 and D5.

What it does not do is treat the disease itself. There is still no cure for Parkinson's, and tavapadon, like every dopamine agonist before it, was approved to treat the motor symptoms. The Michael J. Fox Foundation's principal medical advisor, Rachel Dolhun, put the choice plainly: newer does not always mean better for each individual, and someone whose current regimen is working may not need to change it. The drug has never been tested head to head against the older agonists, so whether its gentler side-effect profile holds up in ordinary use is the open question, and a follow-on study, TEMPO-4, is gathering the longer-term answer. The pill should reach US prescriptions within months. Whether insurers pay for it will take longer to settle.