Objective: To supplement and improve the quality control method hrough a bioassay test about ossotide for injection on inhibiting the proliferation of monocyte-macrophages(THP-1). Method: The biological activity of ossotide for injection was investigated by its inhibitory effect on THP-1 proliferation in vitro with CCK-8 assay. A01160410 batch of ossotide for injection was used as standard control substanceunder the potency determination. Result: The ossotide for injection had a significant inhibitory effect on the proliferation of THP-1.The parallel line(2·2)assay method as the biopotency detection method for inhibitory effect of ossotide for injection on the proliferation of THP-1

had a good repeatability. All the samples passed the reliable test (regression P<0.01

deviation from parallel P>0.05). A20160102 batch of ossotide for injection potency was 94.50 U·mL-1

with confidence limit rate(FL)=6.14%

and the confidence limit range was from 88.87 U·mL-1 to 100.47 U·mL-1;A01160401batch of ossotide for injection potency was 92.04 U·mL-1 with FL=4.36%

and the confidence limit ranged from 88.12 to 96.15 U·mL-1. A01160406 batch of ossotide for injection potency was 83.25 U·mL-1 with FL=8.52%

and the confidence limit ranged from 76.46 to 90.65 U·mL-1. The combined analysis of the experimental results of three batches of ossotide for injection showed that the potency of ossotide for injection for inhibiting THP-1 was 90.37 U·mL-1 with FL=8.63%

and the confidence limit ranged from 82.91 to 98.51 U·mL-1. Different operators had no significant difference in the potency result of ossotide for injection

with a good repeatability. Conclusion: The biopotency detection method established in our study can be used as one of the quality control methods for the bioassay of ossotide for injection.