- After a string of setbacks, including a warning letter, internal staff cuts, leadership changes, and a lawsuit, Impax finally got an FDA approval for Rytary (an oral, extended release formulation of carbidopa-levidopa)—a drug intended for the treatment of Parkinson's disease and other conditions.
- The complete approved indication covers Parkinson's disease, post-encephalitic parkinsonism, and parkinsonism that may follow carbon monoxide intoxication or manganese intoxication .
- Initially, Rytary was being co-developed by Impax and GlaxoSmithKline. However, after the FDA sent a Complete Response Letter for Rytary in 2011 after sending a warning letter to the company regarding a manufacturing plant, GSK backed out.
Persistence has led Impax Labs to score a win with Rytary, but the road to approval was a rocky one.
Many of the challenges centered around manufacturing plant-related problems. After the complete response letter was sent to Impax, the company attempted to remedy problems at the plant and even attempted to manufacture in Taiwan—but the FDA also found the plant in Taiwan lacking.
Finally, in September 2014, the FDA once again delayed its decision on the drug, giving Impax time to address the remaining challenges and start 2015 with a hard-won approval.