Parkinson Therapy IPX203 Continues to Show Increased Good ON Time and Reduced OFF Time in Phase 4 ELEVATE-PD Study

Interim findings from the phase 4 ELEVATE-PD study (NCT06765668) showed that treatment with IPX203 (Crexont; Amneal Pharmaceuticals), an extended-release carbidopa-levodopa formulation, was associated with increased daily Good ON time and reduced OFF time in patients with Parkinson disease (PD) who transitioned from other levodopa-based therapies.¹

In this interim analysis, presented by lead author Stuart Isaacson, MD, FAAN, director for the Parkinson’s Disease and Movement Disorders Center of Boca Raton in Florida, at the 2026 American Academy of Neurology (AAN) Annual Meeting, held April 18–22 in Chicago, Illinois, 55 patients were evaluated (mean age, 66.4 [SD, 8.95] years). At baseline, patients had a mean daily Good ON time of 9.58 hours (SD, 2.36), and OFF time of 5.94 hours (SD, 2.02).

After switching to IPX203, increases in daily Good ON time were observed across prior treatment groups. Patients previously receiving immediate-release (IR) carbidopa-levodopa) had an increase of 3.13 hours (n = 36). Those on IR carbidopa-levodopa plus catechol-O-methyltransferase inhibitors (COMT) inhibitors had an increase of 2.31 hours (n = 6). Patients treated with carbidopa/levodopa (Rytary; Amneal) had an increase of 1.80 hours (n = 11). Reductions in daily OFF time were also reported, with decreases of 2.82, 2.36, and 2.47 hours, respectively.

The ELEVATE-PD study is an ongoing multicenter, open-label, phase 4 trial designed to assess real-world outcomes following a switch to Crexont from existing levodopa-based therapies. These included IR carbidopa-levodopa, IR carbidopa-levodopa combined with COMT, and extended-release formulations like Rytary. Eligible participants were required to have at least 2.5 hours of daily OFF time prior to enrollment. After screening, patients underwent a 5-week dose-optimization period, followed by a 1-week stable dosing phase, with efficacy assessed at Day 42 using patient-reported PD diaries. The primary end point was the change in daily Good ON time from baseline, and the secondary end point was the change in daily OFF time.

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All told, improvements were also observed in Good ON time per dose, which increased by 1.81, 0.77, and 0.78 hours across the respective groups. In addition, Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale total scores decreased by 14.1, 4.2, and 10.8 points, respectively. Moreover, treatment-emergent adverse events were generally mild to moderate, with the most commonly reported events (at least 3%) including nausea (5.5%), falls (3.6%), dizziness (3.6%), and urinary tract infection (3.6%).

In August 2024, the FDA approved IPX203 as a treatment for PD caused by infection or inflammation of the brain, or PD-like symptoms that may result from carbon monoxide or manganese poisoning in adults. It is not recommended in combination with nonselective monoamine oxidase inhibitors, nor with other carbidopa-levodopa preparations without consultation with a healthcare provider.²

The carbidopa-levodopa capsule product was approved based on data from the RISE-PD trial, which showed that those treated with IPX203 at least 3 times per day (n = 256) had a statistically significant improvement of 0.53 hours (95% CI, 0.09-0.97; P = .02) in daily good ON time relative to those on IR CD/LD (n = 250), who were dosed 5 times per day.³ In addition to meeting its primary end point, IPX203 performed well on the secondary end point of change in OFF time hours per day.

All told, treatment with the agent resulted in significantly less OFF time compared with IR carbidopa-levodopa (difference in least square [LS] means, –0.48; 95% CI, –0.90 to –0.06; P = .03). In addition, 29.7% and 18.8% of patients on IPX203 and IR carbidopa-levodopa, respectively, rated themselves as much improved or very much improved on Patient Global Impression of Change (P = .002).

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REFERENCES
1. Isaacson S, Shahed JJ, Soileau M, et al. Switching to CREXONT® Improves “Good On” Time and Reduces Motor Fluctuations in Parkinson’s Disease: Interim Results from the Real-world ELEVATE-PD Phase Four Study. Presented at: 2026 AAN Annual Meeting; April 18-22; Chicago, Illinois.
2. 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. News release. Amneal. August 7, 2024. Accessed April 17, 2026. https://investors.amneal.com/news/press-releases/press-release-details/2024/Amneal-Receives-U.S.-FDA-Approval-for-IPX203-for-Treatment-of-Parkinsons-Disease-to-Be-Launched-as-CREXONT-Carbidopa-and-Levodopa-Extended-Release-Capsules/default.aspx
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. Published online August 14, 2023. doi:10.1001/jamaneurol.2023.2679