The effects of plerixafor on the hemostatic system in patients undergoing stem cell mobilization

Despite numerous reports on the procoagulant activities of G-CSF, the effect of plerixafor on the hemostatic system is not clearly understood. This study aims to evaluate the effects of plerixafor on the hemostatic system when used for autologous stem cell mobilization (ASCM) for poor mobilizers (PM) with lymphoma and multiple myeloma. Patients who were performed ASCM with plerixafor in combination with GCSF were prospectively enrolled. Cohort A included patients mobilized with G-CSF whereas Cohort B included patients mobilized with G-CSF + plerixafor. Blood samples were obtained before the mobilization regimen and just before apheresis. CBC, coagulation tests, CRP, protein C and S, vWF antigen, and factors VIII and XII were studied. Cohort A (n= 30) of which 9 received chemotherapy + G-CSF. Factor VIII, INR, vWF antigen, and CRP significantly increased after G-CSF compared to baseline. Decreases in protein C and S were significant (p<0.001; p=0.005). In cohort B (n=15) no significant changes were observed in coagulation parameters Factor levels, protein C and S before and after the plerixafor. Fibrinogen decreased slightly after plerixafor administration (4.2773±2.2125 vs. 3.6987±1.5062; p=0.02). remained unchanged. In conclusion the addition of plerixafor to G-CSF did not exert further significant procoagulant effects.

Eighteen years experience of granulocyte donations-acceptable donor safety?

BACKGROUND

Granulocyte transfusions are given to patients with life-threatening infections, refractory to treatment. The donors are stimulated with corticosteroids ± granulocyte colony stimulating factor (G-CSF). However, data regarding the donors' safety is sparse. The objective was therefore to evaluate short- and long-term adverse events (AE) in G-CSF stimulated donors.

STUDY DESIGN AND METHODS

All consecutive granulocyte donors from 1994 to 2012 were identified through our registry. From the donation records, the number of aphereses, stimulation therapy, AE, blood values post donation, and recent status were evaluated.

RESULTS

One hundred fifty-four volunteer donors were mobilized for 359 collections. Age at first granulocyte donation was 43 years (median; range 19-64 years). Follow-up was 60 months (median; range 0-229 months). The dose of G-CSF per collection was 3.8 ug/kg body weight (median; range 1.6-6.0 ug/kg). Sedimentation agent was HES. Short-term AE were mild. Blood values 4 weeks post donation with minor reductions/elevations mostly resolved in later donations. Fourteen donors were excluded from the registry due to hypertension (4), diabetes (2), atrial flutter (1), breast carcinoma (1), urethral carcinoma in situ (1), MGUS (1), thrombosis (1), anaphylaxis (1), primary biliary cirrhosis (1), and unknown (1). Three donors are deceased due to diabetes, acute myocardial infarction, and unknown cause. All excluded/deceased donors except one were excluded/died at least 6 months after first granulocyte donation.

CONCLUSION

No serious short-term AE were observed. Due to the variability of diagnoses among excluded/deceased donors, we propose that it is less likely that granulocyte donations have a causative impact on these donors' exclusion or death.

Bone marrow-derived cell mobilization by G-CSF to enhance osseointegration of bone substitute in high tibial osteotomy

PURPOSE

To evaluate granulocyte colony-stimulating factor (G-CSF) efficacy in accelerating bone regeneration following opening-wedge high tibial valgus osteotomy for genu varum.

METHODS

A phase II trial was conducted for evaluating the preoperative administration of G-CSF given at 10 μg/kg/day for 3 consecutive days with an additional half-dose 4 h before the opening-wedge high tibial valgus osteotomy. Overall, 12 patients (Group A) received G-CSF treatment, and the subsequent 12 patients (Group B) underwent surgery without G-CSF. The osteotomy gap was filled by a bone graft substitute. Bone marrow cell (BMC) mobilization was monitored by CD34+ve cell and clonogenic progenitor cell analysis. All patients underwent a clinical (Lysholm Knee Scale and SF-36) and radiographic evaluation preoperatively, as well as at given intervals postsurgery.

RESULTS

All patients completed the treatment program without major side effects; G-CSF was well tolerated. BMC mobilization occurred in all Group A patients, with median peak values of circulating CD34+ve cells of 110/μL (range 29-256). Circulating clonogenic progenitors paralleled CD34+ve cell levels. A significant improvement in Lysholm Knee Scale was recorded at follow-up in Group A compared to Group B. At the radiographic evaluation, there was a significant increase in osseointegration at the bone-graft junction in Group A at 1, 2, 3 and 6 months postsurgery compared to Group B. The computerized tomography scan of the grafted area at 2 months postsurgery showed no significant difference in the quality of the newly formed bone between the two Groups.

CONCLUSIONS

Although the limited number of patients does not allow firm conclusions, the study suggests that G-CSF can be safely administered preoperatively in subjects undergoing opening-wedge high tibial valgus osteotomy; in addition, the clinical, radiographic and CT monitoring indicate that G-CSF and/or mobilized BMCs may hasten bone graft substitute osseointegration.

LEVEL OF EVIDENCE

I.