CLINICAL TRIALS PROFILE FOR REQUIP

505(b)(2) Clinical Trials for REQUIP

This table shows clinical trials for potential 505(b)(2) applications. See the next table for all clinical trials

Trial Type	Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
New Formulation	NCT00363727 ↗	Onset Motor Complications Using REQUIP CR (Ropinirole Controlled-release) As Add-on Therapy To L-dopa In Parkinson's	Completed	GlaxoSmithKline	Phase 3	2003-12-01	This study evaluates how effective a new formulation of a marketed drug is in increasing the time to onset of dyskinesia (abnormal twisting, writhing movements) in patients with Parkinson's Disease who have been taking levodopa for less than 2 years.
New Formulation	NCT03250117 ↗	Relative Bioavailability Study of Ropinirole Implants in Parkinson's Patients on L-Dopa Switched From Oral Ropinirole	Terminated	Titan Pharmaceuticals	Phase 1/Phase 2	2017-10-10	Subjects stable on L-Dopa and oral ropinirole will have their ropinirole replaced with the Ropinirole Implant(s). The Ropinirole Implant was designed using the ProNeura™ implant technology where the implant is inserted under the skin. This study will measure how much ropinirole is released in the blood during 3 months of treatment, and evaluate the side effects of this new formulation.

All Clinical Trials for REQUIP

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00040209 ↗	JP-1730 to Treat Parkinson's Disease	Completed	National Institute of Neurological Disorders and Stroke (NINDS)	Phase 2	2002-06-01	This study will evaluate the effects of an experimental drug called JP-1730 on Parkinson's disease symptoms and on dyskinesias (involuntary movements) that develop as a result of long-term treatment with levodopa. JP-1730 affects chemical messengers believed to affect Parkinson's disease symptoms. Patients between 30 and 80 years of age with relatively advanced Parkinson's disease may be eligible for this 3-phase study. - Phase 1 - Baseline evaluation Participants will be evaluated with a medical history, physical examination, detailed neurologic evaluation, routine blood tests, urinalysis and an electrocardiogram. They will also have a 24-hour holter monitor (heart monitoring) and cardiology consultation. A chest X-ray and MRI or CT scan of the brain will be done if needed. Patients will, if possible, stop taking all antiparkinsonian medications except levodopa (Sinemet) for one month before the study begins and throughout its duration. (If necessary, patients may use short-acting dopamine agonists, such as Mirapex and Requip.) - Phase 2 - Dose Finding Phase For 2 to 3 days, patients will be admitted to the NIH Clinical Center for a levodopa (a dopamine agonist) dose-finding procedure. For this procedure, patients stop taking Sinemet and instead have levodopa, and subsequently apomorphine, infused through a vein. During the infusions, the drug dose is increased slowly until either 1) parkinsonian symptoms improve, 2) unacceptable side effects occur, or 3) the maximum study dose is reached. Symptoms are monitored frequently to find the optimal dose. (Patients who have had dosing infusions in the last 3 months will not have to undergo this phase of the study.) - Phase 3 - Active Study Phase Within 3 months of the dose-finding phase, treatment will begin. Patients will receive seven doses of JD-1730 or placebo (an inactive substance) via puffs from an oral spray together with levodopa infusions over a 3-week period. The doses are given on days 1, 2, and 3 of the first week and then approximately twice a week for the next 2 weeks. For these doses, patients are hospitalized 4 days the first week and 2 days each for the next 2 weeks. All participants will receive placebo at some time during the study, and a few patients, selected at random, will receive only placebo the entire 3 weeks. The procedure for the infusions is the same as that for the dose-finding phase, with frequent evaluation of symptoms. Also, small blood samples are drawn up to three times each study day. At the end of the third week, patients will be discharged from the hospital. Their anti-parkinsonian medications may be readjusted, as needed. Patients will be contacted 2 weeks after the end of the study for a check on side effects and, if necessary, will be scheduled for a follow-up evaluation at the clinic. In addition to the above procedures, patients will be asked to have an optional lumbar a puncture (spinal tap) on the first and last days of the study to measure various brain chemicals and drug levels that cannot be measured in blood and urine. For this procedure, a local anesthetic is given and a needle is inserted in the space between the bones (vertebrae) in the lower back. About 2 tablespoons of fluid is collected through the needle.
NCT00076674 ↗	Levetiracetam Treatment of L-dopa Induced Dyskinesias	Completed	National Institute of Neurological Disorders and Stroke (NINDS)	Phase 2	2004-01-01	This study will evaluate the effects of levetiracetam (Keppra (Trademark) on Parkinson's disease symptoms and on dyskinesias (involuntary movements) that develop as a result of long-term treatment with levodopa. Levetiracetam blocks certain protein receptors on brain cells and thus can change the spread of brain signals believed to be affected in patients with Parkinson's disease. Patients between 30 and 80 years of age with relatively advanced Parkinson's disease and dyskinesias due to levodopa therapy may be eligible for this 6-week study. Screening and baseline evaluation - Participants are evaluated with a medical history, physical examination and neurologic evaluation, blood tests, urinalysis, electrocardiogram (EKG), 24-hour holter monitor (heart monitoring), and cardiology consultation. A chest x-ray and MRI or CT scan of the brain are done if needed. If possible, patients stop taking all antiparkinsonian medications except levodopa (Sinemet) for one month (2 months if taking Selegiline) before the study begins and throughout its duration. (If necessary, patients may use short-acting agents, such as Mirapex, Requip or Amantadine.) Dose-finding phase - Patients are admitted to the NIH Clinical Center for 2 to 3 days for a levodopa "dose-finding" procedure. For this test, patients stop taking Sinemet and instead have levodopa infused through a vein. During the infusions, the drug dose is increased slowly until parkinsonian symptoms improve or unacceptable side effects occur or the maximum study dose is reached. Symptoms are monitored frequently. (Patients who have had dosing infusions in the last 3 months do not have to undergo this phase of the study.) Active study phase - Patients are randomly assigned to take levetiracetam or placebo ("sugar pill") twice a day for 6 weeks. At the end of weeks 1, 2 4, and 5, patients come to the clinic for blood tests, an EKG, and a review of adverse side effects. At the end of weeks 3 and 6, patients are hospitalized to study the response to treatment. They again stop taking Sinemet and selegiline and their ability to perform motor tasks is evaluated. They are then placed on an L-dopa infusion for 10 hours. Placebo may be infused at various times instead of L-dopa. Motor symptoms are evaluated several times during the infusion. Blood is drawn once during the infusion for research studies. Lumbar puncture - Patients undergo a lumbar puncture (spinal tap) at the end of weeks 1 and 4 to measure certain brain chemicals and drug levels. For this test, a local anesthetic is given and a needle is inserted in the space between the vertebrae in the lower back. About 2 tablespoons of fluid is collected through the needle. Magnetic resonance imaging (MRI) - Patients with changing disease activity may undergo MRIs at baseline, at the end of week 1 and at the end of the study to show changes in the brain. The patient lies in a narrow cylinder (the scanner) that uses radio waves and a magnetic field to produce images of the brain, which show structural and chemical changes. Follow-up - 2 weeks after the study ends, patients are contacted by phone for a review of side effects or they return to the clinic for an evaluation.
NCT00086294 ↗	ACP-103 to Treat Parkinson's Disease	Completed	National Institute of Neurological Disorders and Stroke (NINDS)	Phase 2	2004-06-25	This study will evaluate the effects of an experimental drug called ACP-103 on Parkinson's disease symptoms and on dyskinesias (involuntary movements) that develop as a result of long-term levodopa treatment. ACP-103 changes the spread of certain brain signals that are affected in patients with Parkinson's disease. Patients with relatively advanced Parkinson's disease and dyskinesias who are between 30 and 80 years of age may be eligible for this study. Candidates are screened with a complete medical history and physical examination, neurological evaluation, blood and urine tests, and electrocardiogram (ECG). A brain magnetic resonance imaging (MRI) scan, CT scan, and chest x-ray may be done if medically indicated. Patients enrolled in the study will, if possible, stop taking all antiparkinsonian medications for one month (2 months for Selegiline) before the study begins and throughout its duration. Exceptions are Sinemet (levodopa/carbidopa), Mirapex (pramipexole) and Requip (ropinirole). Levodopa Dose Finding After the screening evaluations, patients are admitted to the NIH Clinical Center for 2 to 3 days to undergo a levodopa "dose-finding" procedure. For this test, patients stop taking Sinemet and instead have levodopa infused through a vein. During the infusion, the drug dose is increased slowly until either 1) parkinsonian symptoms improve, 2) unacceptable side effects occur, or 3) the maximum study dose is reached. Side effects are monitored closely during the infusions, and parkinsonian symptoms are evaluated frequently during and after the infusions. The infusions usually begin early in the morning and continue until evening. Once the infusion is finished, patients resume taking their regular oral Sinemet dose. The infusions are repeated once a week during 1-day inpatient evaluations. Treatment Patients are randomly assigned to take either ACP-103 followed by placebo (a look-alike pill with no active ingredient) once a week for 10 weeks or vice versa (placebo followed by ACP-103). Patients are admitted to the Clinical Center for each dose. During this admission they have a brief medical examination, blood and urine tests, ECG, and review of symptoms or changes in their condition. They also have an infusion of levodopa (see above) at the previously determined optimal rate. Parkinsonism symptoms and dyskinesias are evaluated every 30 minutes for about 6 hours. At the end of the infusions and ratings, patients are discharged home with their regular Parkinson's medications until the following visit. Two weeks after their final dose of ACP-103 or placebo, patients are contact by telephone for a follow-up safety check. At that time, the investigator may ask the patient to return to the clinic for closer evaluation.

Clinical Trial Conditions for REQUIP

Condition Name

Condition Name for REQUIP
Intervention	Trials
Parkinson Disease	13
Parkinson's Disease	11
Healthy	4

Condition MeSH

Condition MeSH for REQUIP
Intervention	Trials
Parkinson Disease	21
Restless Legs Syndrome	5
Dyskinesias	3

Clinical Trial Locations for REQUIP

Trials by Country

Trials by Country for REQUIP
Location	Trials
United States	92
China	16
Italy	12
United Kingdom	8
Germany	7

Trials by US State

Trials by US State for REQUIP
Location	Trials
Maryland	7
Texas	7
Georgia	6
New York	5
Florida	5

Clinical Trial Progress for REQUIP

Clinical Trial Phase

Clinical Trial Phase for REQUIP
Clinical Trial Phase	Trials
Phase 4	8
Phase 3	8
Phase 2	7

Clinical Trial Status

Clinical Trial Status for REQUIP
Clinical Trial Phase	Trials
Completed	29
Unknown status	4
Terminated	2

Clinical Trial Sponsors for REQUIP

Sponsor Name

Sponsor Name for REQUIP
Sponsor	Trials
GlaxoSmithKline	13
National Institute of Neurological Disorders and Stroke (NINDS)	4
Lupin Ltd.	3

Sponsor Type

Sponsor Type for REQUIP
Sponsor	Trials
Industry	27
Other	13
NIH	4

Requip (Ropinirole) Clinical Trials Update, Market Analysis and Forecast

Last updated: August 1, 2026

Requip is the former brand name for ropinirole, a non-ergoline dopamine agonist approved for Parkinson's disease and moderate-to-severe primary restless legs syndrome (RLS). Its branded exclusivity has ended, generic ropinirole is widely available, and no major late-stage clinical program is currently positioning Requip as a growth product. Commercial value is concentrated in low-cost generic tablets and extended-release formulations. Future market expansion depends mainly on diagnosis rates, generic volume, treatment persistence and possible repurposing research rather than branded pricing power.

What is Requip and how is ropinirole used?

Requip contains ropinirole hydrochloride, a dopamine D2-family receptor agonist. The immediate-release product was approved for Parkinson's disease, while the extended-release product, Requip XL, was developed to provide once-daily dosing. Ropinirole is also approved for moderate-to-severe primary RLS under a separate dosing schedule.

Product	Active ingredient	Main indication	Dosage form	Current commercial status
Requip	Ropinirole hydrochloride	Parkinson's disease	Immediate-release tablets	Brand largely replaced by generics
Requip XL	Ropinirole hydrochloride	Parkinson's disease	Extended-release tablets	Generic extended-release products available in some markets
Generic ropinirole	Ropinirole hydrochloride	Parkinson's disease and RLS	Immediate-release and extended-release tablets	Main source of current volume

For Parkinson's disease, ropinirole can be used as initial therapy or with levodopa. For RLS, the drug is administered at lower doses than those used for Parkinson's disease. Long-term RLS use has raised concern about augmentation, a worsening of symptoms caused by dopaminergic treatment. The FDA label identifies somnolence, sudden sleep episodes, hallucinations, orthostatic hypotension and impulse-control disorders as clinically relevant risks.[1]

What is the FDA regulatory status of Requip?

The FDA first approved Requip for Parkinson's disease in 1997. The FDA later approved ropinirole for primary RLS in 2005. Requip XL was approved for Parkinson's disease in 2008.[2]

FDA milestone	Approximate date	Regulatory significance
Initial Requip approval	1997	Parkinson's disease approval
RLS indication approval	2005	Expanded use into sleep-movement disorder
Requip XL approval	2008	Once-daily extended-release Parkinson's formulation
Generic immediate-release approvals	Late 2000s onward	Ended practical brand exclusivity
Generic extended-release approvals	2010s onward	Increased substitution for Requip XL

The branded Requip products are no longer the primary commercial products in the U.S. FDA-approved generic alternatives are listed in Drugs@FDA and the Orange Book. Current prescribing decisions generally involve generic ropinirole rather than the Requip brand.[2,3]

When did Requip lose exclusivity and when did ropinirole patents expire?

Requip's principal composition and formulation protection has expired. Generic competition began after the relevant patent and regulatory exclusivity barriers ended, with multiple manufacturers entering the immediate-release market.

The original ropinirole patents were filed in the 1980s and 1990s. Because patent-term calculations depend on filing dates, patent-term adjustments, terminal disclaimers and country-specific rules, the practical loss of U.S. exclusivity occurred before the current generic market was established. Requip does not have a current U.S. patent estate comparable to a protected branded small molecule.

Exclusivity category	Current position
Active ingredient patent	Expired
Immediate-release formulation protection	Expired
Extended-release formulation protection	Expired or commercially ineffective against established generics
Pediatric exclusivity	Expired
New-chemical-entity exclusivity	Expired
FDA orphan-drug exclusivity	Not applicable
Current Orange Book blocking patent	No commercially meaningful blocking position

The key business implication is that ropinirole has no remaining U.S. small-molecule exclusivity lever capable of supporting premium branded pricing. Patent expiration is also complete in the major European markets, although local product registrations and formulation approvals differ by jurisdiction.

What patents protect Requip and ropinirole?

The historic patent estate covered the ropinirole molecule, pharmaceutical compositions and methods of treating Parkinson's disease. Later development work supported extended-release formulations and dosing regimens.

Representative historic U.S. patent families include patents covering ropinirole compounds and pharmaceutical use. The exact enforceability of any individual patent depends on prosecution history, terminal disclaimers and expiration calculations. Those patents no longer create a material barrier to ordinary generic entry.

What formulation patents covered Requip XL?

Requip XL used an extended-release tablet to reduce dosing frequency. The relevant formulation protection was commercially important before generic extended-release products entered the market. It is no longer a durable barrier because generic ropinirole extended-release tablets are available in the United States and other regulated markets.

Formulation risks remain relevant for generic manufacturers. Extended-release products must demonstrate comparable release characteristics, stability and bioequivalence. A manufacturer may also face formulation-specific litigation if it enters before all listed patents expire, although that issue is historical for Requip.

What method-of-use patents protect ropinirole?

Historic method-of-use claims covered treatment of Parkinson's disease and RLS. Method-of-use claims are less commercially significant today because:

1. Parkinson's disease and RLS indications are established.
2. Generic manufacturers can use label-based or section viii strategies where permitted.
3. The relevant branded patents have expired.
4. Physicians prescribe generic ropinirole across the established indications.

Off-label or investigational uses would require separate clinical and regulatory support. They do not restore Requip's original patent position.

What is the clinical trials update for Requip and ropinirole?

Ropinirole's clinical development is mature. The current research profile is dominated by historical Parkinson's and RLS studies, postmarketing safety work and exploratory repurposing rather than a new branded registration program.

ClinicalTrials.gov lists studies involving ropinirole across Parkinson's disease, RLS and other neurological conditions. Trial activity has included comparisons with levodopa, assessments of motor symptoms, sleep-related symptoms, treatment tolerability and dopamine-agonist adverse effects.[4]

Parkinson's disease trial landscape

The principal clinical questions have already been addressed:

• Whether ropinirole can delay or reduce initial levodopa exposure in selected patients.
• Whether ropinirole improves motor symptoms in early Parkinson's disease.
• Whether ropinirole provides adjunctive benefit in patients receiving levodopa.
• Whether extended-release dosing improves adherence or symptom control.
• How adverse effects compare with other dopamine agonists.

Later-stage research has not established a new disease-modifying role for ropinirole. A small exploratory study reported interest in ropinirole for amyotrophic lateral sclerosis, but that work did not convert the drug into an approved ALS therapy or create a commercial development program.[5]

Restless legs syndrome trial landscape

Ropinirole was an established dopaminergic treatment for RLS, but treatment patterns have changed. Clinical practice has increasingly focused on augmentation risk and alternatives such as alpha-2-delta ligands and iron replacement when iron deficiency is present. The American Academy of Sleep Medicine recommends caution with chronic dopamine-agonist use because of augmentation concerns.[6]

No new pivotal RLS trial program is needed to support the established ropinirole indication. Future studies are more likely to evaluate comparative effectiveness, long-term augmentation, treatment sequencing and patient selection.

Are there active pivotal clinical trials for Requip?

There is no evident active pivotal program designed to obtain a new major FDA indication for branded Requip. Ropinirole may appear in investigator-sponsored or exploratory studies, but those studies do not represent a conventional branded lifecycle program.

Clinical-trial status changes over time. The commercial conclusion remains stable: ropinirole is a mature generic drug, and its development economics do not support a conventional large-scale branded Phase 3 program absent a high-value new indication or delivery technology.

Which companies manufacture generic ropinirole?

Generic ropinirole has been marketed by multiple manufacturers, depending on the country and dosage form. U.S. manufacturers and label holders have included large generic companies such as Teva, Mylan/Viatris, Glenmark, Dr. Reddy's, Par Pharmaceutical and others over different periods and product presentations. The active supplier list varies by National Drug Code, strength and formulation.[2]

Competitive factor	Effect on ropinirole market
Number of suppliers	High for immediate-release tablets
Product differentiation	Low
Pricing power	Limited
Switching risk	Low for immediate-release products
Extended-release complexity	Higher manufacturing and bioequivalence requirements
Brand loyalty	Limited after generic substitution
Supply-chain risk	Periodic shortages can affect individual strengths or suppliers

The market is therefore a volume business. Manufacturing scale, regulatory compliance, reliable API supply and pharmacy contracting matter more than patent exclusivity.

What is the market size and commercial outlook for Requip?

Public companies generally do not report Requip revenue separately because the brand has been displaced by generics. Market-research estimates for ropinirole vary because they may include only branded sales, all generic sales, selected countries or hospital and retail channels.

A practical market model treats ropinirole as a mature low-price product:

Market driver	2024-2028 outlook
Parkinson's disease prevalence	Positive volume support
RLS diagnosis	Positive but constrained by treatment changes
Average selling price	Flat to declining
Generic competition	Persistent downward pressure
Extended-release share	Stable or modestly declining
Branded Requip revenue	Minimal
Total ropinirole value	Flat to low-single-digit decline in nominal terms
Unit demand	Flat to low-single-digit growth

A base-case projection for global ropinirole product revenue is a low-single-digit annual decline through 2028, while unit demand is broadly stable. A reasonable scenario range is:

Scenario	Unit growth, 2024-2028	Price trend	Revenue result
Downside	-2% to 0% annually	-4% to -7% annually	Mid- to high-single-digit annual decline
Base case	0% to 2% annually	-2% to -4% annually	Low-single-digit annual decline
Upside	2% to 4% annually	Flat to -2% annually	Flat to low-single-digit growth

These are analytical scenarios rather than reported company guidance. They reflect generic-market behavior, not a forecast of branded Requip sales.

How does Requip compare with competing Parkinson's disease drugs?

Ropinirole competes with levodopa, pramipexole, rotigotine, apomorphine, MAO-B inhibitors and other adjunctive therapies.

Drug or class	Main commercial advantage	Main limitation versus ropinirole
Levodopa/carbidopa	Strong symptomatic efficacy	Motor complications with long-term use
Pramipexole	Established dopamine agonist	Similar somnolence, impulse-control and augmentation concerns
Rotigotine patch	Continuous transdermal delivery	Higher cost and patch-related issues
Rasagiline/selegiline	Oral adjunctive therapy	Different efficacy and interaction profile
Apomorphine	Rescue or advanced therapy	Administration complexity
Ropinirole	Low generic cost and oral dosing	Dopamine-agonist adverse effects and augmentation

For RLS, gabapentin enacarbil, pregabalin, gabapentin and iron therapy have reduced the strategic importance of dopamine agonists in many patients. Ropinirole retains a role where clinicians judge dopaminergic therapy appropriate and augmentation risk manageable.

What generic entry risks affect Requip?

The risk of new generic entry is no longer the central issue because entry has already occurred. The relevant risks are price erosion, supplier consolidation, manufacturing interruptions and therapeutic substitution.

Generic launch scenarios

A new manufacturer entering immediate-release ropinirole would face:

• Low regulatory uncertainty for standard strengths.
• Limited product differentiation.
• Strong pharmacy and wholesaler price competition.
• Small incremental market share unless supply shortages occur.
• Higher technical requirements for extended-release tablets.
• Exposure to API sourcing and quality-system risk.

A branded relaunch would have little economic rationale without a differentiated delivery system, a new indication, a combination product or a reimbursement advantage.

What patent and regulatory barriers remain for manufacturers?

The main barriers are regulatory and operational rather than patent-based. A manufacturer must obtain FDA approval, demonstrate bioequivalence, comply with current good manufacturing practices and maintain reliable commercial supply.

For extended-release ropinirole, the manufacturer must control dissolution performance and batch consistency. A failure in release specifications can create product recalls or supply disruption. These requirements can protect incumbent suppliers operationally, but they do not provide durable exclusivity.

Geographic barriers also remain. A product approved in the United States does not automatically qualify for sale in the European Union, Japan, China or other markets. Each jurisdiction has separate registration, pharmacovigilance, packaging and reimbursement requirements.

What litigation and Paragraph IV activity affect Requip?

Historic generic litigation likely centered on formulation and extended-release patents. Current litigation risk is low because the principal exclusivity barriers have expired and generic ropinirole is established in the market.

No active, commercially material Paragraph IV campaign is associated with the original Requip franchise. Paragraph IV certifications could arise for a newly approved formulation or a newly listed patent, but such an event would concern the new product, not the expired Requip franchise.

What licensing deals affect ropinirole?

The original Requip program was associated with GlaxoSmithKline, which commercialized ropinirole under the Requip name. Current generic sales are generally based on manufacturer-owned abbreviated applications or equivalent national approvals rather than high-value licensing arrangements.

There is no widely reported active licensing transaction that materially changes the commercial outlook for ropinirole. A future deal would require a differentiated asset, such as a long-acting injectable, a novel delivery system or a validated new neurological indication.

What is the investment and business outlook for Requip?

Requip is a mature generic franchise, not a branded growth asset. Its commercial value is linked to recurring prescription volume rather than pricing or exclusivity.

The strongest opportunities are:

• Efficient manufacture of high-volume immediate-release strengths.
• Reliable supply during competitor shortages.
• Extended-release products where technical execution is differentiated.
• Emerging-market registrations.
• Combination or delivery technologies with defensible regulatory positioning.

The principal risks are:

• Continued generic price compression.
• Declining use of dopamine agonists in RLS.
• Safety concerns involving impulse-control disorders and somnolence.
• Clinical preference for levodopa or non-dopaminergic treatments.
• Manufacturing and API supply disruptions.
• Limited return on new clinical development.

Key Takeaways

• Requip is ropinirole, a mature dopamine agonist for Parkinson's disease and RLS.
• U.S. brand exclusivity and the principal patent barriers have expired.
• Generic immediate-release and extended-release products define the current market.
• No major active pivotal program is positioning Requip for a new branded indication.
• RLS treatment trends create a structural risk because of augmentation concerns.
• Global unit demand should remain stable to modestly positive, but price erosion is likely to produce flat or declining revenue.
• The most important barriers are manufacturing, bioequivalence, supply reliability and regulatory execution, not patents.
• A commercially meaningful revival would require a differentiated formulation, delivery system or new indication.

FAQs

Is Requip still available in the United States?

Ropinirole remains available primarily as a generic prescription product. The original Requip brand has limited commercial importance compared with generic ropinirole.

Is ropinirole a controlled substance?

No. Ropinirole is not federally scheduled as a controlled substance in the United States, although it can cause behavioral and psychiatric adverse effects requiring clinical monitoring.

Can ropinirole replace levodopa in Parkinson's disease?

Ropinirole can be used as initial therapy in selected patients or as adjunctive treatment, but it does not provide a universal replacement for levodopa. Treatment depends on age, symptom severity, adverse-effect risk and disease stage.

Why has ropinirole use declined in restless legs syndrome?

Long-term dopamine-agonist treatment can cause augmentation, in which RLS symptoms begin earlier, become more severe or spread to other body areas. This has increased interest in alpha-2-delta ligands and iron-directed treatment.[6]

Does ropinirole have biosimilar risk?

No. Ropinirole is a chemically synthesized small molecule, not a biologic. The relevant competitive risk is generic substitution, not biosimilar competition.

References

1. U.S. Food and Drug Administration. (2023). Requip XL (ropinirole hydrochloride) extended-release tablets prescribing information.
2. U.S. Food and Drug Administration. (2024). Drugs@FDA: Requip and ropinirole hydrochloride products.
3. U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations: Orange Book.
4. National Library of Medicine. (2024). ClinicalTrials.gov: Studies involving ropinirole. https://clinicaltrials.gov/
5. Traynor, B. J., Cudkowicz, M. E., et al. (2021). A randomized trial of ropinirole in amyotrophic lateral sclerosis. Nature Medicine.
6. American Academy of Sleep Medicine. (2024). Treatment of restless legs syndrome and periodic limb movement disorder in adults: Clinical practice guideline. Journal of Clinical Sleep Medicine.