IL-11 is a member of a family of human growth factors and is being produced in the bone marrow of healthy adults.

[2] In mice and nonhuman primate studies Neumega has shown potent thrombopoietic activity in compromised hematopoiesis, including moderately to severely myelosuppressed animals.

In a second study in which single 75 μg/kg subcutaneous and intravenous doses were administered to twenty-four healthy subjects, the pharmacokinetic profiles were similar between men and women.

Pediatric cancer patients treated with aggressive chemotherapy showed similar pharmakinetic characteristics.

Isolated molecules formed under oprelvekin were found to have exact the same multimere structure as the 'normal' factor and were therefore fully functioning.

These increases in coagulation factors may contribute to the development of stroke (see under § Side effects), but a precise association cannot be made at this stage.

In a variety of clinical studies upon which FDA approval is based, Neumega showed effectivity in reducing thrombocytopenia in oncologic patients treated with myelosuppressant chemotherapeutic drugs as measured by significantly decreased need of platelet transfusions.

The drug is formulated in single-use vials containing 5 mg of oprelvekin (specific activity approximately 8 × 106 units/mg) as a sterile, lyophilized powder.

In studies with rats and rabbits treated chronically, Oprelvekin showed embryo- and fetotoxicity (early death of embryos and reduction of number of fetus, fetal malformations etc.).

Nursing women should either discontinue breast-feeding or Neumega, the decision should take into account the importance of the drug to the mother.

Symptoms have been edema of the face and tongue, or larynx; shortness of breath; wheezing; chest pain; hypotension (including shock); dysarthria; loss of consciousness, rash, urticaria, flushing, and fever.

[medical citation needed] The concomitant application of GM-CSFs such as filgrastim or Sargramostim showed no potential interactions.

The dosage in patients without severe renal impairment is 50 μg/kg subcutaneously once a day either abdominal, in thigh, or hip.