Comparative safety of filgrastim versus sargramostim in patients receiving myelosuppressive chemotherapy

STUDY OBJECTIVE

To compare rates of adverse events with filgrastim versus sargramostim when given prophylactically to patients receiving myelosuppressive chemotherapy.

DESIGN

Retrospective review with center crossover.

SETTING

Ten United States outpatient chemotherapy centers.

PATIENTS

Four hundred ninety patients treated for lung, breast, lymphatic system, or ovarian tumors.

INTERVENTION

Prophylactic use of filgrastim or sargramostim, with dosages at investigator discretion.

MEASUREMENTS AND MAIN RESULTS

The frequency and severity of adverse events and the frequency of switching to the alternative CSF were assessed. There was no difference in infectious fever. Fever unexplained by infection was more common with sargramostim (7% vs 1%, p<0.001), as were fatigue, diarrhea, injection site reactions, other dermatologic disorders, and edema (all p<0.05). Skeletal pain was more frequent with filgrastim (p=0.06). Patients treated with sargramostim switched to the alternative agent more often (p<0.001).

CONCLUSION

Adverse events were less frequent with filgrastim than with sargramostim, suggesting that quality of life and treatment costs also may differ.

Randomized trial comparing the tolerability of sargramostim (yeast-derived RhuGM-CSF) and filgrastim (bacteria-derived RhuG-CSF) in cancer patients receiving myelosuppressive chemotherapy

A prospective, randomized, double-blind, multicenter study in cancer patients receiving myelosuppressive chemotherapy was undertaken to evaluate and compare the tolerability of sargramostim (yeast-derived recombinant human granulocyte-macrophage colony-stimulating factor, RhuGM-CSF) and filgrastim (bacteria-derived recombinant human granulocyte colony-stimulating factor, RhuG-CSF) in the prophylaxis or treatment of chemotherapy-induced neutropenia. In all, 137 evaluable patients received sargramostim (300 micrograms; 193 mg/m2) or filgrastim (481 mg; 7 mg/kg) once daily by self-administered s.c. injection, usually beginning within 48 h after completion of chemotherapy. With the exception of a slightly higher incidence of grade 1 fever (< 38.1 degrees C) with sargramostim, there were no statistically significant differences in the incidence or severity of local or systemic adverse events possibly related to the growth factors. Although the study was not designed to evaluate efficacy directly, there also were no statistically significant differences between treatment groups in total days of growth factor therapy, days of hospitalization, or days of i.v. antibiotic therapy during the treatment period. Both sargramostim and filgrastim were comparably well tolerated when given by s.c. injection in this group of patients, and no clinically significant differences between the growth factors were demonstrated.

Iron malabsorption in a patient with large cell lymphoma involving the duodenum

Iron malabsorption compounded the anemia in a patient with diffuse large cell lymphoma involving the small intestine. Both upper gastrointestinal series with small bowel follow-through and computerized tomographic scan demonstrated lymphomatous involvement of the duodenum and proximal jejunum by a retroperitoneal mass. An oral iron-loading absorption test was consistent with malabsorption of iron. After two cycles of systemic chemotherapy, the retroperitoneal mass resolved and the iron loading test normalized.

Early diagnosis of spinal metastases by CT and MR studies

Fifteen patients with known metastatic or high-risk primary cancer, normal neurologic examinations, and new abnormalities on 99mTc bone scan were evaluated with spinal CT and magnetic resonance (MR) imaging. Four patients underwent CT metrizamide myelography. Spinal CT and MR agreed in 14 of 15 patients demonstrating spinal metastases in 12 patients and benign disease in two. In one patient spinal CT was normal, but MR showed altered marrow signal consistent with metastatic disease. Epidural tumor was demonstrated by CT metrizamide myelography in four cases, all correctly identified by MR. Further evaluation of spinal MR in this setting is warranted.