Tavapadon in Parkinson's disease

Tavapadon is an oral, once-daily, highly selective dopamine D1/D5 receptor partial agonist evaluated for the treatment of Parkinson's disease (1,2):

• unlike traditional non-ergot dopamine agonists (e.g. pramipexole, ropinirole) which preferentially target D2/D3 receptors, tavapadon selectively activates D1/D5 receptors to stimulate the direct motor pathway while minimising motor fluctuations and D2-mediated adverse effects (1,2)
• phase 3 evidence from the TEMPO trial program demonstrates efficacy both as monotherapy in early Parkinson's disease and as adjunctive therapy to levodopa in patients with motor fluctuations (1,3)

Mechanism of action

• acts as a partial agonist at D1 and D5 dopamine receptors with high functional selectivity (1)
• targeted activation of direct pathway striatal neurons aims to restore motor control while avoiding overstimulation, potentially offering an improved therapeutic window with reduced dyskinesia and somnolence (1)

Summary of phase 3 TEMPO clinical trials

TEMPO-1 (early Parkinson's disease monotherapy – fixed dose)

• evaluated fixed doses of tavapadon (5 mg or 15 mg daily) versus placebo over 26 weeks in patients with early Parkinson's disease (3)
• primary endpoint achieved: significant improvement in combined MDS-UPDRS Part II (activities of daily living) and Part III (motor exam) scores at week 26 compared with placebo (3)
• both 5 mg and 15 mg cohorts demonstrated clinically meaningful motor improvements (-11.4 and -12.1 points vs placebo, P<0.001) (3)

TEMPO-2 (early Parkinson's disease monotherapy – flexible dose)

• evaluated flexible dosing of tavapadon (5–15 mg daily) versus placebo over 26 weeks in early Parkinson's disease (2,3)
• significantly improved combined MDS-UPDRS Part II and III scores compared with placebo (-10.3 vs -1.2 points, P<0.0001) (2,3)
• significantly improved MDS-UPDRS Part II (daily living activities) scores alone (-1.5 vs 0.0, P=0.0007) (2)

TEMPO-3 (adjunctive therapy with levodopa in motor fluctuations)

• evaluated tavapadon (5–15 mg daily) as an add-on therapy to levodopa over 27 weeks in patients experiencing motor "off" times (1)
• primary endpoint achieved: statistically significant increase in total daily "ON" time without troublesome dyskinesia compared with placebo (+1.1 hours improvement over placebo, P<0.001) (1)
• resulted in a concordant reduction in daily "OFF" time of approximately 1 hour compared with placebo (-0.94 hours, P<0.001) (1)

TEMPO-4 (long-term open-label extension)

• evaluated durability and safety out to 85 weeks across monotherapy and adjunctive trial cohorts (1,2)
• levodopa sparing effect: among patients receiving tavapadon monotherapy for 85 weeks, 94% (257/273) did not require initiation of levodopa (2)
• dose stability: among patients receiving adjunctive tavapadon plus levodopa for 85 weeks, 93% (96/103) did not require an increase in their baseline levodopa dose (2)

Adverse Effects and Safety Profile

• monotherapy adverse events: most common included nausea (25.4%), headache (16.7%), dizziness (12.7%), fatigue, vomiting, dry mouth and anxiety (3)
• adjunctive adverse events: most common included nausea, dyskinesia, dizziness, headache, hallucinations and orthostatic hypotension (1)
• class-related precautions: clinicians must monitor for orthostatic hypotension, dyskinesia risk, somnolence/sudden sleep onset and impulse control disorders (gambling, hypersexuality, compulsive buying) (1,2)

References:

1. Fernandez HH, Isaacson SH, Hauser RA, et al. Tavapadon as adjunctive treatment for Parkinson disease: the TEMPO-3 randomized clinical trial. JAMA Neurol. 2026;83(5):442-451. doi:10.1001/jamaneurol.2026.0577
2. AbbVie Inc. U.S. FDA approves AbbVie's JUVMO (tavapadon) for Parkinson's disease. Published Sep 2026.
3. Pahwa R, Moro E, Espay AJ, et al. Fixed-dose tavapadon for early Parkinson disease: a randomized clinical trial. JAMA Neurol. 2026;83(5):452-460