lesinurad/allopurinol (DSC)

Drug Overview

Living with uncontrolled gout is a profoundly painful experience. When sharp uric acid crystals accumulate in the joints, they trigger sudden, agonizing attacks that can make even walking or putting on a shoe feel impossible. For patients whose gout is resistant to standard treatments, the field of Rheumatology provides advanced options. This guide details lesinurad/allopurinol, a unique combination medication within the Uricosuric and Xanthine Oxidase (XO) Inhibitor drug classes.

This medication acts as a dual-mechanism Targeted Therapy, combining two different approaches into one tablet. Please note that this specific combination carries a “lesinurad/allopurinol (DSC)” (Discontinued) status in the US market. This discontinuation was primarily driven by corporate manufacturing decisions rather than immediate safety recalls, and understanding its medical profile remains highly relevant for the continued study of combination gout therapies.

• Generic Name: lesinurad and allopurinol
• US Brand Names: Duzallo (DSC)
• Route of Administration: Oral tablet
• FDA Approval Status: FDA-approved (Currently discontinued in the US market)

What Is It and How Does It Work? (Mechanism of Action)

Gout is caused by hyperuricemia, a condition where there is too much uric acid in the blood. This happens either because the body produces too much uric acid, or the kidneys fail to excrete enough of it. Lesinurad/allopurinol is an oral Small Molecule therapy that addresses both problems simultaneously by combining two powerful active ingredients.

The first ingredient, allopurinol, is a xanthine oxidase (XO) inhibitor. At a molecular level, it binds to and blocks the enzyme xanthine oxidase, which the body uses to manufacture uric acid. By shutting down this factory, allopurinol drastically reduces the total amount of uric acid being produced.

The second ingredient, lesinurad, works directly in the kidneys. Normally, kidney proteins known as URAT1 and OAT4 reabsorb uric acid from the urine and put it back into the bloodstream. Lesinurad selectively blocks these transporter proteins. Without them acting as a reabsorption vacuum, the body can successfully flush the excess uric acid out through the urine. By reducing production and increasing excretion at the exact same time, this drug aggressively lowers blood uric acid levels, dissolving existing crystals and preventing new ones from forming.

FDA-Approved Clinical Indications

Primary Indication: Lesinurad/allopurinol is indicated for the treatment of hyperuricemia associated with gout in patients who have not achieved their target serum uric acid levels with allopurinol alone.

Other Approved & Off-Label Uses:

Because this medication strictly targets uric acid pathways, it is exclusively used for gout management. It is not prescribed for other autoimmune or rheumatological conditions such as Rheumatoid Arthritis, Psoriatic Arthritis, Systemic Lupus Erythematosus (SLE), or Ankylosing Spondylitis.

Primary Rheumatology Indications:

In the management of severe, uncontrolled gout, this dual therapy is used to achieve the following:

• Aggressively lower serum uric acid (sUA) levels to a target of less than 6.0 mg/dL.
• Promote the rapid shrinking and complete dissolution of tophi (painful, visible lumps of uric acid crystals beneath the skin and inside the joints).
• Prevent long-term structural joint damage and bone erosion caused by chronic crystal deposition, thereby preserving the patient’s mobility and physical function.

Dosage and Administration Protocols

This medication provides a fixed-dose combination to simplify the patient’s daily routine, ensuring that lesinurad is never taken without a base layer of allopurinol.

Dose Adjustments and Considerations:

Kidney function is absolutely paramount when dosing this medication. It is strictly contraindicated in patients with severe renal impairment (an eGFR of less than 30 mL/min), end-stage renal disease, or patients on dialysis. It is also not recommended to start this drug if a patient’s eGFR is below 45 mL/min. Patients transitioning to this drug must take it in the morning with food and water.

Dosage must be individualized by a qualified healthcare professional.

Clinical Efficacy and Research Results

While Duzallo is discontinued, clinical reviews and retrospective studies published between 2020 and 2026 continue to highlight its clinical trial data as a benchmark for dual-mechanism gout therapy.

During the primary clinical trials, the combination of lesinurad and allopurinol proved highly efficacious for patients failing standard therapy. Data revealed that approximately 54% of patients taking the dual combination successfully achieved the strict serum uric acid target of less than 6.0 mg/dL by month six, compared to roughly 28% of patients taking allopurinol alone.

By maintaining these low uric acid levels, the medication stops the continuous inflammatory attacks that degrade cartilage. Imaging and long-term observational data show that keeping uric acid consistently below 6.0 mg/dL allows joint lesions to heal and significantly slows the radiographic progression of bone erosion, effectively halting the structural damage associated with advanced gout.

Safety Profile and Side Effects

BLACK BOX WARNING: This medication carries a severe Black Box Warning for Acute Renal Failure. The lesinurad component significantly increases the risk of acute kidney injury. To mitigate this, lesinurad must always be taken in combination with an XO inhibitor like allopurinol, which this combination pill ensures.

Common Side Effects (>10%):

• Headache
• Influenza-like symptoms
• Gastroesophageal reflux disease (GERD)
• Skin rash

Serious Adverse Events:

• Acute renal failure and kidney stone formation.
• Severe hypersensitivity reactions, including Stevens-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN), primarily driven by the allopurinol component.
• Major Adverse Cardiovascular Events (MACE), which are actively monitored in all uricosuric drugs.
• Hepatotoxicity (liver injury).

Management Strategies:

Patients must stay incredibly well-hydrated, drinking at least 2 liters of water daily to flush the kidneys. Routine blood tests to monitor serum creatinine (kidney function) and liver enzymes are mandatory.

Research Areas

In modern rheumatology research (2020-2026), the legacy of lesinurad/allopurinol has driven the development of safer, next-generation combination therapies. Current active clinical trials are intensely focused on discovering new Small Molecule uricosurics that do not carry the same high risks of renal failure, while still providing the immense benefits of dual-mechanism uric acid lowering.

Furthermore, severe disease and systemic involvement are major areas of study. Researchers are heavily investigating the connection between chronic hyperuricemia and severe cardiovascular disease. Current data suggests that unmanaged gout is not just a joint disease, but a systemic inflammatory state that damages blood vessels. Studying how medications clear uric acid helps researchers map how driving down uric acid might simultaneously reduce a patient’s risk of heart attacks and chronic kidney disease progression.

Disclaimer: The research discussed regarding next-generation combination uricosuric therapies and the systemic pathways linking chronic hyperuricemia to cardiovascular disease and chronic kidney disease progression is currently in the preclinical or early investigational phase and is not yet applicable to practical or professional clinical scenarios. 

Patient Management and Clinical Protocols

Pre-treatment Assessment

• Baseline Diagnostics: Comprehensive joint X-rays or ultrasound to document existing bone erosions and the size of tophi. Baseline pain scores are recorded.
• Organ Function: A complete metabolic panel is critical to establish baseline kidney function (eGFR and serum creatinine) and hepatic markers (LFTs).
• Specialized Testing: Genetic screening for the HLA-B*5801 allele is highly recommended for patients of Asian or African descent before starting any drug containing allopurinol, as this gene significantly increases the risk of severe, life-threatening skin reactions.
• Screening: Baseline cardiovascular risk assessment.

Monitoring and Precautions

• Vigilance: Doctors will frequently monitor serum uric acid and kidney function, especially in the first few months. Patients must be warned that gout “flares” often temporarily increase when starting this medication, as old crystals begin to dissolve and shift in the joints. Doctors typically prescribe a low-dose anti-inflammatory for the first six months to prevent these flares.
• Lifestyle: A low-purine, anti-inflammatory diet is essential. Patients must restrict alcohol, high-fructose corn syrup, and red meat.

Do’s and Don’ts

• DO drink at least 2 liters of water every single day to protect your kidneys.
• DO take this medication in the morning with food and a full glass of water.
• DO stop the medication and seek emergency care immediately if you develop a skin rash, as this can be a sign of a severe allergic reaction.
• DON’T stop taking the medication during a gout flare unless told to do so by your doctor.
• DON’T become dehydrated; avoid excessive sweating without fluid replacement.

Legal Disclaimer

The information provided in this article is for educational and informational purposes only and does not constitute medical advice. Treatment plans, dosages, and medication choices must be individualized by a qualified healthcare professional. Always consult your physician or specialist rheumatologist before starting, stopping, or altering any medical treatment.