Educational content on VJNeurology is intended for healthcare professionals only. By visiting this website and accessing this information you confirm that you are a healthcare professional.

This content is for healthcare professionals only.

Please confirm you are a healthcare professional.

Yes
No

Introduction

Over the past few years, the treatment landscape for movement disorders has continued to evolve. Landmark clinical trials have supported the approval of novel therapies and advanced a growing pipeline of emerging treatments for Parkinson’s disease (PD), Huntington’s disease, essential tremor, and Tourette syndrome. This review summarizes key pharmacologic advances across these disorders and their potential to reshape future clinical practice.

Oral modified-release carbidopa-levodopa for Parkinson’s disease

In PD, recent advances in dopaminergic therapies have focused on improving the pharmacokinetic profile of levodopa-based treatments. One notable development is IPX203, an extended-release oral formulation of levodopa/carbidopa that received U.S. Food and Drug Administration (FDA) approval in 2024 and was recently approved by the European Medicines Agency (EMA) in August 2026, underscoring its growing regulatory momentum.1,2 The formulation is designed with extended-release pellets that deliver levodopa in a controlled manner, enabling more sustained absorption and reduced fluctuations in drug levels.3 In the Phase III RISE-PD trial (NCT03670953), IPX203 was observed to significantly increase daily ON time compared with immediate-release levodopa/carbidopa, with nausea and dyskinesia reported as the most common adverse events.3

Infusion-based dopamine agonists for Parkinson’s disease

Despite advances in oral dopamine agonist therapy, many patients still experience motor fluctuations and “off” periods when medication wears off. As a result, the development of infusion-based therapies has become a major focus of PD research. Notably, the FDA approval of foslevodopa/foscarbidopa in 2024 introduced the first 24-hour continuous subcutaneous infusion of a levodopa-based therapy.4 This combination delivers stable levodopa and carbidopa concentrations, reducing the fluctuations associated with intermittent oral dosing and has demonstrated favorable efficacy and safety outcomes in the Phase III M15-736 trial (NCT04380142).5

At the 2026 American Academy of Neurology (AAN) Annual Meeting, Katarina Rukavina, MD, PhD, Movement Disorders Hospital, Beelitz, Germany, shared further insights into the real-world experience with foslevodopa/foscarbidopa infusion in patients with advanced PD.

Apomorphine also expanded treatment options in the US in 2025, following FDA approval of continuous subcutaneous infusion via a wearable pump designed to provide sustained dopaminergic stimulation and more consistent control of motor symptoms throughout the day.6 This addition expands the range of infusion therapies available to patients with advanced PD who experience motor fluctuations. The approval was based on the Phase III TOLEDO trial (NCT02006121), in which apomorphine reduced daily OFF time by approximately 1.89 hours compared with placebo.7 Together, these infusion therapies provide important options for patients whose symptoms remain inadequately controlled with oral medications alone.

We spoke with Francesca Morgante, MD, PhD, St George’s University of London, London, United Kingdom, at the 2026 Congress of the European Academy of Neurology (EAN), who discussed key efficacy and safety outcomes from the TOLEDO trial.

 

Tavapadon for Parkinson’s disease 

Another exciting development is the emergence of tavapadon, an oral, once-daily dopamine D1/D5 receptor partial agonist, which is currently under FDA review for adjunctive treatment to levodopa in people with mild to moderate PD and motor fluctuations.8 By selectively targeting D1/D5 receptors, tavapadon aims to improve motor control while minimizing some of the adverse effects associated with conventional dopamine agonists. In the recently published Phase III TEMPO-3 trial (NCT04542499), tavapadon met its primary endpoint and demonstrated a safety profile consistent with previous studies, supporting its potential as a promising new therapeutic option.9

 

“For many years we thought that dopamine agonists would be effective only if they acted on the dopamine D2 receptor subgroup. But in recent years we have learned that also D1 is very important in Parkinson’s functionality and mobility. Tavapadon is the first D1 agonist that comes to clinical use.” – Angelo Antonini, MD, PhD, University of Padua, Padua, Italy.

Ulixacaltamide for essential tremor

Another major development is the emergence of ulixacaltamide for the treatment of essential tremor, which was granted New Drug Application (NDA) acceptance by the FDA in April 2026, with a PDUFA target action date of January 29, 2027.10 Ulixacaltamide is a first-in-class therapy designed to modulate tremor circuits by reducing abnormal neuronal burst firing within the brain.10 Positive topline findings from the Phase III Essential3 study (NCT06087276) were presented at AAN 2026, highlighting ulixacaltamide’s potential as a first-in-class therapy that could redefine the treatment landscape for essential tremor.11

“Since there’s nothing readily available, to have something that is pharmacologically mechanistically appropriate that has been shown to be effective is very exciting. It’s also been shown to be well-tolerated in the studies, so it has the potential for very strong clinical utility.” – Jill Farmer, DO, MPH, Drexel University College of Medicine, Philadelphia, PA.

 

Ecopipam for Tourette syndrome

Progress in Tourette syndrome management has recently advanced with the NDA acceptance by the FDA and priority review for ecopipam, an investigational, first-in-class selective dopamine D1 receptor antagonist.12 This follows Phase IIb data demonstrating significant reductions in tic severity and the recently published Phase III D1AMOND trial (NCT05615220), which demonstrated durable efficacy, with ecopipam meeting both primary and secondary endpoints and showing a favorable safety and tolerability profile.12 These findings are particularly important in a condition where existing therapies are often limited by significant adverse effects, highlighting ecopipam’s potential to address a longstanding unmet need. The FDA has assigned a PDUFA target action date in late Q1 2027.12

At AAN 2026, Kinga Tomczak, MD, PhD, Boston Children’s Hospital, Boston, MA, spoke on these promising results and the prospect of FDA approval: “this is currently being actually under an FDA commission process, it will take several months, and it’s hard to know when the drug will be available, we hope maybe at the end of 2026, but it could be 2027”.

Ifezuntirgene inilparvovec for Huntington’s disease

Ifezuntirgene inilparvovec (AMT-130) represents a significant advancement for Huntington’s disease, with the submission of a Biologics License Application (BLA) to the FDA for accelerated approval.13 Ifezuntirgene inilparvovec is an investigational gene therapy delivered as a single MRI-guided stereotactic injection into the striatum and uses a miRNA to silence the huntingtin gene and its potentially toxic exon 1 fragment. If approved, ifezuntirgene inilparvovec would be the first available therapy with the potential to slow disease progression, representing a significant advance for patients with Huntington’s disease.13

In a recent interview, Victor Sung, MD, University of Alabama, Birmingham, AL, shared insights into the 3-year data from the Phase I/II trial (NCT04120493) supporting the BLA submission, highlighting efficacy, tolerability and safety outcomes of ifezuntirgene inilparvovec.

Conclusion

The field of movement disorders has seen significant breakthroughs, with several emerging therapies poised to reshape clinical practice in the near future. Advances span from novel dopaminergic strategies in PD to innovative approaches in Huntington’s disease, essential tremor, and Tourette syndrome. Ongoing research will continue to refine these therapies and further improve outcomes for patients living with movement disorders.

 

References

  1. Amneal. Amneal Receives U.S. FDA Approval for IPX203 for Treatment of Parkinson’s Disease to Be Launched as CREXONT® (Carbidopa and Levodopa) Extended-Release Capsules. Available here. (Last accessed 07/06/2026).
  2. Zambon Pharma. Zambon announces European Commission approval of Hopledo® for Adults with Parkinson’s Disease and Moderate to Severe Motor Fluctuations. Available here. (Last accessed 07/06/2026).
  3. Hauser RA, Espay AJ, Ellenbogen AL, et al. IPX203 vs Immediate-Release Carbidopa-Levodopa for the Treatment of Motor Fluctuations in Parkinson Disease: The RISE-PD Randomized Clinical Trial. JAMA Neurol. 2023;80(10):1062-1069.
  4. Abbvie. U.S. FDA Approves VYALEV™ (foscarbidopa and foslevodopa) for Adults Living with Advanced Parkinson’s Disease. Available here. (Last accessed 07/06/2026).
  5. Soileau MJ, Aldred J, Budur K, et al. Safety and efficacy of continuous subcutaneous foslevodopa-foscarbidopa in patients with advanced Parkinson’s disease: a randomised, double-blind, active-controlled, phase 3 trial. Lancet Neurol. 2022;21(12):1099-1109.
  6. Supernus. Supernus Announces FDA Approval of ONAPGO™ (apomorphine hydrochloride) for Parkinson’s Disease. Available here. (Last accessed 07/06/2026).
  7. Katzenschlager R, Poewe W, Rascol O, et al. Apomorphine subcutaneous infusion in patients with Parkinson’s disease with persistent motor fluctuations (TOLEDO): a multicentre, double-blind, randomised, placebo-controlled trial. Lancet Neurol. 2018;17(9):749-759.
  8. The Micheal J. Fox Foundation. Once-Daily Treatment for Parkinson’s Motor Symptoms Submitted for FDA Approval. Available here. (Last accessed 07/06/2026).
  9. 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.
  10. Praxis. Praxis Precision Medicines Announces FDA Acceptance of New Drug Application for Ulixacaltamide HCl in Patients with Essential Tremor. Available here. (Last accessed 09/09/2026).
  11. AAN 2026. Combined Efficacy and Safety of Ulixacaltamide in Essential Tremor: Topline Results from the Phase 3 Essential3 Program. Available here. (Last accessed 07/06/2026).
  12. Teva. U.S. FDA Accepts Teva’s New Drug Application (NDA) and Grants Priority Review for Ecopipam, a First-in-Class Investigational Therapy for Pediatric Patients with Tourette Syndrome. Available here. (Last accessed 09/09/2026).
  13. uniQure. uniQure Announces Submission of Biologics License Application for Ifezuntirgene Inilparvovec (AMT-130) in Huntington’s Disease. Available here. (Last accessed 09/09/2026).
Written by Clare Harris
Reviewed by Hannah Elkheir
Publishing date: 15 September, 2026
The content of VJNeurology is intended for healthcare professionals