Molidustat

Indications

Varenzin-CA1 is indicated for the control of nonregenerative anemia associated with chronic kidney disease (CKD) in cats.

Dosage and Administration

Shake well before use. The dosage of Varenzin-CA1 is 2.3 mg/lb (5 mg/kg) body weight (bw) administered orally once daily for up to 28 consecutive days. Treatment may be repeated after a minimum 7-day pause (see Monitoring and Repeating Treatment ). Varenzin-CA1 should be administered using the dosing syringe provided in the package. The dosing syringe is marked in increments of 0.1 mL. The dose should be rounded up to the nearest 0.1 mL. Dosing Information To ensure the correct dose is administered, body weight should be determined prior to starting each treatment cycle. Table 1. Dosing Chart Weight Range in pounds (lb) Volume of Varenzin-CA1 (mL) 3.4 to 4.4 0.4 4.5 to 5.5 0.5 5.6 to 6.6 0.6 6.7 to 7.7 0.7 7.8 to 8.8 0.8 8.9 to 9.9 0.9 10 to 11 1 11.1 to 12.1 1.1 12.2 to 13.2 1.2 Note: The syringe included with the Varenzin-CA1 product cannot be used to accurately dose cats weighing under 3.4 pounds. Cats greater than 13.2 lb bw should be treated with a dose of 2.3 mg/lb bw rounded up to the nearest 0.1 mL. Administration Shake well before use. Remove screw cap. Use the enclosed syringe for each treatment. Place the syringe nozzle firmly into the opening of the bottle. Turn the bottle upside down and withdraw the necessary volume. Turn the bottle back into an upright position before removing the syringe. The product should be administered with the syringe into the cat’s mouth. See illustrations 1 through 4 below for administration steps: After administration, close bottle tightly with cap and store syringe in the carton together with the product. Do not disassemble or wash the syringe. The product should be given once daily for up to 28 consecutive days. If the cat vomits after consuming any portion of the dose, the cat should not be re-dosed and should be considered as dosed for the day. Monitoring and Repeating Treatment Treated cats should initially have their hematocrit (HCT) or packed cell volume (PCV) levels monitored weekly beginning about the 14 th day of the 28-day treatment cycle to ensure HCT or PCV does not exceed the upper limit of the reference range. Discontinue Varenzin-CA1 if HCT or PCV exceeds the upper limit of the reference range. After treatment cessation the hematocrit level should be periodically checked (for example, weekly, every 2 weeks or monthly). When the HCT or PCV level declines below the lower limit of the reference range, a new treatment cycle should be started. The interval between treatment cycles will vary between cats and may change over time for an individual cat but should be at least 7 days. If a cat does not respond to treatment after 3 weeks (see REASONABLE EXPECTATION OF EFFECTIVENESS ), it is recommended to re-examine the animal for any other underlying condition that may contribute to anemia, such as iron deficiency, inflammatory diseases or blood loss. It is advised to treat the underlying condition before restarting treatment with Varenzin-CA1. Administration Steps

Contraindications

Varenzin-CA1 should not be administered to cats with known hypersensitivity to molidustat or to any of the inactive ingredients. Varenzin-CA1 should not be administered to cats that are pregnant, lactating, or intended for breeding. In an embryo-fetal-developmental toxicity study in rats, an increase incidence of ocular malformations such as flat eye rudiments and microphthalmia were observed at doses of 30 mg/kg bw per day. These effects may be due to an increase in oxygen availability, caused by molidustat-induced polycythemia. Localized hypoxia is an important factor in normal eye development. Developmental toxicity studies have not been conducted in cats. Available animal data have shown excretion of other HIF-PH inhibitors into milk. It is unknown whether molidustat is excreted into the milk of lactating cats.

Warnings

User Safety Warnings Not for use in humans. Keep this drug, including used syringes, out of reach of children. Wash hands immediately after use and/or spillage. In case of accidental ingestion, seek medical advice immediately and show the package leaflet or the label to the physician. Symptoms of exposure to molidustat may include the following: gastrointestinal effects (nausea, vomiting, diarrhea), blood and clotting effects (increases in reticulocytes, erythropoietin, and hemoglobin), dizziness, fainting, hypertension, changes in cardiac output and cardiac index, and increases in heart rate. Symptoms may not occur immediately; therefore, the exposed individual should be monitored. People with known hypersensitivity to molidustat sodium should avoid direct contact with this product and should administer the product with caution. Women who are pregnant or may become pregnant should administer the product with caution. Molidustat administered orally to pregnant rats during the period of organogenesis was associated with adverse fetal outcomes (see

Precautions

Varenzin-CA1 has been associated with thromboembolic disease (see

Adverse Reactions

). Use with caution in cats that may be predisposed to thromboembolic disease. Use with caution in cats with a history of seizures (see ADVERSE REACTIONS ). Phosphate binders or other products containing multivalent cations such as calcium, iron, magnesium or aluminum have been shown to chelate with other HIF-PH inhibitors. Based on information in humans, consider staggered administration of Varenzin-CA1 and phosphate binders and iron supplements (at least 1 hour apart), if possible, to prevent potentially decreasing absorption of molidustat. Polycythemia may result from use of Varenzin-CA1. When starting Varenzin-CA1, cats should have their hematocrit (HCT) or packed cell volume (PCV) levels monitored regularly during the treatment cycle to ensure HCT or PCV does not exceed the upper limit of the reference range (see

Description

Varenzin-CA1 (molidustat oral suspension) is a white to yellow-white oily suspension. Each mL of Varenzin-CA1 contains 25 mg of molidustat sodium. The inactive ingredients are glycerol dibehenate, fish oil, sunflower oil, butylhydroxytoluene, and sorbic acid. The empirical formula is C 13 H 13 N 8 O 2 Na and the molecular weight is 336.28. The chemical name is Sodium 1-[6-(morpholin-4-yl)pyrimidin-4-yl]-4-(1H-1,2,3-triazol-1-yl)-1H-pyrazol-5-olate. The chemical structure of molidustat sodium is: Chemical Structure

Storage

Store at controlled room temperature 20°C – 25°C (68°F – 77°F). Excursions permitted between 15°C and 30°C (59°F – 86°F).

FDA adverse event reports

The FDA Center for Veterinary Medicine publishes the adverse event reports it receives through openFDA. The counts below are the reports naming molidustat as an active ingredient for each species this label names, as returned on 2026-09-16, coded by the VeDDRA reaction term the reporter chose. Reactions are counted per report, so one report can appear under several terms.

These are counts, not rates. Reporting is voluntary, the number of animals treated is not known, and a widely used product accumulates reports for that reason alone. A report records that an event followed a dose; it does not establish that the product caused it. The counts say nothing about how one product compares with another.