The What’s Hot in Parkinson’s disease blog written in April 2013 featured a new extended release dopamine drug called IPX066. This new dopamine formulation achieved full FDA approval in January 2015. The drug is now sold under the name Rytary. At National Parkinson Foundation we frequently hear from Parkinson’s disease patients that current carbidopa/levodopa medication preparations fail to adequately address disease-related symptoms. In this month’s What’s Hot column we will update you on important information on Rytary, and also offer a few tips for switching.
Medication dosages taking too long to “kick in” and start working
Too many medication dosage intervals (e.g. taking medications every 1-2 hours
The new formulation of carbidopa/levodopa extended release (IPX066/Rytary), is different than its predecessors. It contains special beads designed to dissolve at different rates within the stomach and the intestines. The medication capsule was designed to provide longer lasting benefit for patients with Parkinson’s disease. The randomized study included 393 Parkinson’s disease patients who reported at least of 2.5 hours of “off time,” defined as periods when they felt the medication was not working. The authors aimed to improve the number of hours of “off time” each day for patients randomized to the new extended release formulation (IPX066/Rytary) as compared to the older and standard regular release carbidopa/levodopa. The results revealed that the group on extended release formulations took less overall medication dosages (3.6 vs. 5 doses per day); however they also took more total pills. The daily “off-time” improved by over an hour each day in the extended release formulation. Both medications in this trial were safe and well tolerated.
If we return to the six areas (listed above in bullet points) where Parkinson’s disease patients have been seeking improved medication formulations, Rytary was observed to improve issues in two categories: wearing off between dosages, and improvement by increasing the time interval between dosages. The results of the current study cannot be widely applied to patients with severe dyskinesia, severe on-off fluctuations, and later stage disease. The new extended release formulation also increased the total blood-stream levodopa exposure by 30-40% as compared to conventional immediate release levodopa. Increasing levodopa in the bloodstream is thought to decrease the threshold for dyskinesia, and this has been observed with other Parkinson’s drugs such as Entacapone and Stalevo. Although dosed less frequently, the extended release formulation can require more total pills per day (see FDA conversion table below). The authors of the Rytary study felt that a newer formulation of the same drug, which they anticipate will be used in future clinical practice, would allow for a decrease in pill number.
Though it is unknown who the “best” patients in clinical practice will be, it is suspected that
benefit could possibly be obtained by adding a dose of Sinemet or Madopar rather than
There may be select patients who can take a Rytary dose that is approximately three times
Dosages of Rytary are not interchangeable with other levodopa (Sinemet or Madopar)
The capsules can be opened and the contents sprinkled onto foods such as apple sauce, if
The most important information for patients and families is to avoid magical thinking when
It will be important for the patient, family, and doctor to discuss the symptoms and optimize
The FDA label on Rytary provides a nice chart on general (approximate) recommendations
1: Pahwa R, Lyons KE, Hauser RA, Fahn S, Jankovic J, Pourcher E, Hsu A, O'Connell M, Kell S, Gupta S; APEX-PD Investigators. Randomized trial of IPX066, carbidopa/levodopa extended release, in early Parkinson's disease. Parkinsonism Relat Disord. 2014 Feb;20(2):142-8. doi: 10.1016/j.parkreldis.2013.08.017. Epub 2013 Sep 5. PubMed PMID: 24055014.
2: Hauser RA, Hsu A, Kell S, Espay AJ, Sethi K, Stacy M, Ondo W, O'Connell M, Gupta S; IPX066 ADVANCE-PD investigators. Extended-release carbidopa-levodopa (IPX066) compared with immediate-release carbidopa-levodopa in patients with Parkinson's disease and motor fluctuations: a phase 3 randomised, double-blind trial. Lancet Neurol. 2013 Apr;12(4):346-56. doi: 10.1016/S1474-4422(13)70025-5. Epub 2013 Feb 26. PubMed PMID: 23485610.
3: Hauser RA. IPX066: a novel carbidopa-levodopa extended-release formulation. Expert Rev Neurother. 2012 Feb;12(2):133-40. doi: 10.1586/ern.11.195. Review. PubMed PMID: 22288668.
4: http://www.accessdata.fda.gov/drugsatfda_docs/label/2015/203312s000lbl.pdf
5: Okun MS. Parkinson’s Treatment: 10 Secrets to a Happier Life. Createspace, 2013.
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