Source – Amneal Pharmaceuticals
On July 3, 2023, Amneal Pharmaceuticals’ plans to launch its extended-release Parkinson’s disease treatment, IPX203, by midyear have been delayed. The FDA rejected the company’s application for IPX203, which is an oral formulation of carbidopa/levodopa (CD/LD) that combines immediate-release CD/LD granules with extended-release LD-coated beads.
The goal of IPX203 is to increase the duration of the therapeutic benefit of the drug and reduce involuntary body movements, providing more “on” time for Parkinson’s patients with fewer doses compared to existing formulations.
“We are committed to advancing IPX203 for Parkinson’s disease, which has been developed to provide a longer duration of therapeutic benefit than existing formulations with fewer doses. We plan to work closely with the FDA to address the agency’s feedback and we remain confident in bringing this new treatment to Parkinson’s patients as soon as possible.”
- Chirag and Chintu Patel, Co-Chief Executive Officers at Amneal
The FDA’s complete response letter highlighted inadequate safety data regarding the CD component of the drug and emphasized the need for additional pharmacokinetic information. However, the FDA did not raise concerns about the LD element or the efficacy and manufacturing of IPX203, as stated in a press release by Amneal.
Levodopa has been the standard treatment for Parkinson’s patients for over 50 years, but motor complications such as peak-dose dyskinesia and “off” episodes are common. IPX203’s approval is crucial for Amneal to maintain its competitive position in Parkinson’s disease, especially since its marketed product Rytary is expected to lose patent protection in 2028.
It remains uncertain how much of an impact IPX203 will have on treatment patterns for doctors and patients. Interviews with key opinion leaders suggest that the efficacy advantage of IPX203 over immediate-release LD formulations may not be significant enough to influence treatment decisions, especially if IPX203 is priced at a premium.
IPX203 may also face competition from other innovative subcutaneous levodopa delivery systems, such as AbbVie’s ABBV-951 and NeuroDerm’s ND0612, which offer continuous infusion of CD/LD and could provide additional options for controlling motor fluctuations in advanced-stage Parkinson’s patients. AbbVie’s ABBV-951 recently encountered its own setback when the FDA questioned the subcutaneous pump device associated with the treatment.
IPX203 features a unique formulation that includes a disintegrant polymer for rapid dissolution of immediate-release granules, sustained-release polymer-coated LD beads for slow drug release, a mucoadhesive polymer to prolong adherence to the absorption area, and an enteric coating to prevent premature disintegration in the stomach.
While Rytary has had limited success, Amneal sees IPX203 as a much larger opportunity in the Parkinson’s disease market. The company aims for peak annual net
sales of $300 million to $500 million in the United States, making IPX203 the most promising product in its branded specialty pipeline.
