Sucroferric Oxyhydroxide API is an iron-based, non-calcium phosphate binder used for the control of elevated serum phosphorus levels in patients with chronic kidney disease who are receiving dialysis. It is the active pharmaceutical ingredient of Velphoro and works by binding dietary phosphate in the gastrointestinal tract, thereby reducing phosphate absorption.
Sucroferric Oxyhydroxide is a distinctive pharmaceutical material composed of a polynuclear iron(III)-oxyhydroxide core stabilized with a carbohydrate shell containing sucrose and starches. Because of this composition, the material is characterized as a mixture rather than as a conventional single molecular entity. USP describes it using the general composition FeHO₂·xC₁₂H₂₂O₁₁·y(C₆H₁₀O₅)ₙ.
Sucroferric Oxyhydroxide is described as a brown amorphous powder that is practically insoluble in water. The active substance consists of polynuclear iron(III)-oxyhydroxide together with sucrose and starch components.
The substance does not have a meaningful fixed molecular weight because its composition includes variable quantities of sucrose and polymeric starch. Therefore, a single conventional molecular-weight value should not be used as the definitive API molecular weight in a pharmaceutical specification. USP likewise represents the composition with variable x, y and n terms.
Sucroferric Oxyhydroxide is a phosphate binder. It binds phosphate in the gastrointestinal tract through interactions involving the hydroxyl groups and/or water associated with the iron(III)-oxyhydroxide structure. The resulting phosphate-containing material is eliminated through the feces, reducing dietary phosphate absorption.
Velphoro is indicated for controlling serum phosphorus levels in patients with chronic kidney disease on dialysis. Each marketed 500-mg-iron chewable tablet contains 2,500 mg of sucroferric oxyhydroxide, equivalent to 500 mg of iron.
Phosphate-binding capacity is a critical functional characteristic of Sucroferric Oxyhydroxide. Unlike a conventional small-molecule API, functional phosphate adsorption is an important part of its characterization.
Experimental studies demonstrate phosphate binding across physiologically relevant pH conditions, with particularly strong binding under acidic conditions. One study reported phosphate adsorption as high as 0.26 mg phosphorus per mg iron under tested conditions.
Process-development literature has reported phosphate-binding capacity values such as at least 0.20 mg P/mg Fe and approximately 3.7 mEq phosphate per 500 mg iron for a particular manufacturing process. These values should be treated as process/product-specific analytical characteristics rather than as a universal pharmacopoeial release limit.
Quality control of Sucroferric Oxyhydroxide requires characterization appropriate to its complex composition. Relevant analytical parameters may include:
USP's proposed drug-substance monograph includes dedicated analytical procedures for iron, sucrose and starch, confirming that these components are central to the analytical characterization of the material.
Swapnroop Drugs and Pharmaceuticals provides pharmaceutical API manufacturing and quality-focused capabilities for active pharmaceutical ingredients and specialized pharmaceutical materials.
Sucroferric Oxyhydroxide can be evaluated according to applicable customer, regulatory and product-specific specifications, with analytical characterization focused on composition, iron content and functional phosphate-binding performance.
Sucroferric Oxyhydroxide is moisture-sensitive and should be stored in suitable protective packaging. The marketed product is stored at 25°C, with permitted excursions to 15–30°C, and the container should remain tightly closed to protect the material from moisture.
Depending on applicable requirements, documentation may include:
Sucroferric Oxyhydroxide requires specialized characterization because its pharmaceutical performance depends on the properties of its iron oxyhydroxide core and carbohydrate components. Swapnroop focuses on controlled pharmaceutical manufacturing, analytical quality evaluation and documentation support for specialized API requirements.
| Parameter | Specification |
|---|---|
| Appearance | white to off-white crystalline powder |
| Identification | IR & HPLC compliant |
| Assay (HPLC) | 98.0% – 102.0% |
| Loss on Drying | NMT 0.5% |
| Heavy Metals | NMT 10 ppm |
| Water Content | NMT 0.5% |