Darbepoetin Alfa Injection

Darbepoetin alfa injection (brand name Aranesp) is a red blood cell-stimulating agent approved for the following uses:

• Anemia due to chronic kidney disease (CKD) — Aranesp is approved for adults and children aged 1 month and older, both on dialysis and not on dialysis
• Anemia caused by myelosuppressive chemotherapy — Aranesp is approved for adults with non-myeloid cancers when anemia is due to ongoing chemotherapy and at least two more months of chemotherapy are planned
• Aranesp is not approved for cancer patients receiving only radiation therapy, hormonal therapy, or biologic therapy (unless also receiving myelosuppressive chemotherapy)
• Aranesp is not approved when the goal of cancer treatment is a cure, or as an emergency substitute for a red blood cell transfusion

Darbepoetin alfa works just like your body's own erythropoietin — a hormone made mainly by the kidneys that tells the bone marrow to produce red blood cells. In people with CKD, the kidneys don't make enough erythropoietin, so red blood cell counts fall. In people on certain chemotherapy, the bone marrow is suppressed. Aranesp steps in to send that "make more red blood cells" signal, helping to raise hemoglobin levels and reduce the need for blood transfusions. It typically takes 2 to 6 weeks before hemoglobin levels begin to rise noticeably.

Aranesp is given as an injection — either into a vein (intravenous) or just under the skin (subcutaneous) — never by mouth. The intravenous route is recommended for CKD patients on hemodialysis. For cancer patients on chemotherapy, Aranesp is given subcutaneously.

• For CKD patients on dialysis: typically given once weekly or once every two weeks
• For CKD patients not on dialysis: typically given once every four weeks
• For cancer patients on chemotherapy: given weekly or once every three weeks, and stopped when the chemotherapy course ends

Your prescriber will monitor your hemoglobin regularly and adjust the dose as needed. Never adjust your dose on your own — always follow your care team's instructions.

Like all medicines, Aranesp can cause side effects. The most common ones reported in clinical studies include:

• High blood pressure (hypertension)
• Shortness of breath (dyspnea)
• Swelling in the legs or feet (peripheral edema)
• Cough
• Low blood pressure during a medical procedure (procedural hypotension)
• Abdominal pain and general swelling (edema) — more common in cancer patients
• Rash or skin redness
• Injection site pain (more commonly reported in children)

More serious reactions — including heart attack, stroke, blood clots, seizures, severe allergic reactions, and a rare condition called pure red cell aplasia (PRCA, where the bone marrow stops making red blood cells) — have been reported and require immediate medical attention.

• Increased risk of death, heart attack, stroke, and blood clots: Targeting hemoglobin levels above 11 g/dL in CKD patients significantly increases these risks. Always use the lowest effective dose.
• Tumor growth and shorter survival in cancer patients: ESAs like Aranesp have been linked to faster tumor progression and reduced survival in multiple cancer types. It should only be used for chemotherapy-related anemia when a cure is not the expected outcome.
• High blood pressure: Aranesp can raise or worsen blood pressure. It must not be started if blood pressure is not under control, and monitoring is required throughout treatment.
• Seizures: Aranesp increases seizure risk in CKD patients — report any changes in seizure frequency or warning signs to your doctor right away.
• Pure red cell aplasia (PRCA): A rare but serious condition where the bone marrow stops producing red blood cells, sometimes triggered by antibodies to the drug. If severe anemia develops during treatment, your doctor should evaluate for PRCA.
• Serious allergic and skin reactions: Stop Aranesp and seek immediate care if you experience hives, difficulty breathing, or severe skin blistering or peeling.

The FDA label for Aranesp does not list specific drug, food, or supplement interactions. Always tell your prescriber and pharmacist about every medication, supplement, and herbal product you take so they can check for potential concerns.

This is not a complete list of interactions. Always talk with your doctor or pharmacist before starting, stopping, or changing any medication.

• Uncontrolled high blood pressure: Aranesp is contraindicated — blood pressure must be controlled before starting treatment
• History of PRCA after using Aranesp or another erythropoietin drug: Do not use Aranesp
• Prior serious allergic reaction to Aranesp: Do not use Aranesp
• Heart disease or prior stroke: Use with extreme caution and close monitoring — the risk of serious cardiovascular events is higher
• Cancer patients aiming for a cure: Aranesp is not appropriate in this setting
• Pregnancy: Limited human data; animal studies showed some risk at doses near the clinical starting dose. Discuss benefits and risks with your doctor
• Breastfeeding: It is unknown if Aranesp passes into breast milk; discuss with your doctor before use
• Children with CKD: Aranesp is approved for ages 1 month and older; safety and effectiveness have not been established for children with cancer
• Iron levels: Iron status must be checked before and during treatment; iron supplements are commonly needed, especially in CKD
• Latex allergy: The needle cover of the Aranesp prefilled syringe contains natural rubber (a derivative of latex) and may cause allergic reactions

Taking too much Aranesp can push hemoglobin levels higher than intended, which increases the risk of serious cardiovascular events. Severe high blood pressure has also been reported after an overdose. If an overdose is suspected, the dose is reduced or stopped, and in some cases a procedure to remove excess blood (phlebotomy) may be used — your medical team will decide the best approach.

Aranesp stimulates the bone marrow to produce more red blood cells, which raises the hemoglobin level in the blood. However, this effect is not immediate — hemoglobin levels generally do not rise noticeably until 2 to 6 weeks after starting treatment. The goal is to raise hemoglobin enough to reduce the need for red blood cell transfusions, without pushing it too high.

When Aranesp is given intravenously to CKD patients on dialysis, it is cleared from the body with a half-life of about 21 hours — roughly three times longer than a related drug, epoetin alfa. When given subcutaneously (under the skin), absorption is slower, with peak blood levels reached around 48 hours after injection; the half-life is longer still — about 46 hours in dialysis patients and around 70 hours in CKD patients not on dialysis. In cancer patients receiving subcutaneous doses, the half-life averages about 74 hours. This longer duration in the body is why Aranesp can be dosed less frequently than older erythropoietin drugs.

Store at 36°F to 46°F (2°C to 8°C). Do not freeze. Protect from light; store Aranesp in the carton until use.