Neuroprotective therapy using granulocyte colony-stimulating factor for patients with worsening symptoms of compression myelopathy, part 1: a phase I and IIa clinical trial

Objective

Based on the neuroprotective effects of granulocyte colony-stimulating factor (G-CSF) on experimental spinal cord injury, we initiated a clinical trial that evaluated the safety and efficacy of neuroprotective therapy using G-CSF for patients with worsening symptoms of compression myelopathy.

Methods

We obtained informed consent from 15 patients, in whom the Japanese Orthopaedic Association (JOA) score for cervical myelopathy decreased two points or more during a recent 1-month period. G-CSF (5 or 10 μg/kg/day) was intravenously administered for five consecutive days. We evaluated motor and sensory functions of the patients and the presence of adverse events related to G-CSF therapy.

Results

G-CSF administration suppressed the progression of myelopathy in all 15 patients. Neurological improvements in motor and sensory functions were obtained in all patients after the administration, although the degree of improvement differed among the patients. Nine patients in the 10-μg group (n = 10) underwent surgical treatment at 1 month or later after G-CSF administration. In the 10-μg group, the mean JOA recovery rates 1 and 6 months after administration were 49.9 ± 15.1 and 59.1 ± 16.3%, respectively. On the day following the start of G-CSF therapy, the white blood cell count increased to more than 22,700 cells/mm³. It varied from 12,000 to 50,000 and returned to preadministration levels 3 days after completing G-CSF treatment. No serious adverse events occurred during or after treatment.

Conclusion

The results indicate that G-CSF administration at 10 μg/kg/day is safe for patients with worsening symptoms of compression myelopathy and may be effective for their neurological improvement.