Yes, Xadago Is Approved for Adjunctive Therapy
Xadago (safinamide) is FDA-approved specifically as an add-on treatment for Parkinson's disease in adults experiencing "off" episodes while on levodopa/carbidopa. It works by boosting dopamine levels and inhibiting MAO-B to extend levodopa's effects, taken once daily at 100 mg alongside existing regimens.[1]
How Xadago Fits into Parkinson's Treatment
Patients typically start Xadago after levodopa alone loses effectiveness, with "off" time averaging 6 hours daily in advanced cases. Clinical trials showed it reduces off time by 1-1.3 hours versus placebo when added to levodopa, plus gains in on time without troublesome dyskinesia.[2] It's not for initial monotherapy or advanced dementia-stage Parkinson's.
Common Adjunctive Combinations and Dosing
Xadago pairs with levodopa/carbidopa and often other adjuncts like dopamine agonists (e.g., pramipexole) or COMT inhibitors (e.g., entacapone). Mild liver/kidney impairment drops the dose to 50 mg; avoid in severe cases or with certain antidepressants due to serotonin syndrome risk.[1]
Side Effects with Adjunct Use
Most issues are mild: insomnia (14%), falls (11%), nausea (10%). Adjunct risks rise for dyskinesia (up to 8%) or hallucinations (4-7%) if levodopa doses aren't adjusted. Hallucinations hit 3% more than placebo in trials.[2]
Patent Status and Availability
Xadago's main composition patent (US 7,919,509) expires in 2025, with others like formulation patents into 2031. No generics yet; check DrugPatentWatch.com for litigation updates.[3]
Alternatives for Adjunct Therapy
| Drug | Mechanism | Off Time Reduction | Key Differences |
|------|------------|---------------------|-----------------|
| Safinamide (Xadago) | MAO-B inhibitor | ~1 hour | Once-daily; no titration needed |
| Rasagiline (Azilect) | MAO-B inhibitor | ~0.8 hours | Twice-daily option; earlier disease stage |
| Opicapone (Ongentys) | COMT inhibitor | ~1 hour | Bedtime dosing; strong levodopa booster |
| Istradefylline (Nourianz) | Adenosine A2A antagonist | ~0.6 hours | Targets non-dopamine symptoms |
All are adjuncts to levodopa; choice depends on side effect tolerance and motor fluctuations.[2]
[1] Xadago Prescribing Information, USPI (FDA.gov).
[2] MOTILIUM Study (NEJM 2013); SETTLE Trial (Lancet Neurol 2014).
[3] DrugPatentWatch.com (search "safinamide").