14 CLINICAL STUDIES
A total of 554 subjects were enrolled, in a multicenter, open-label, observational study (MOSAIC) conducted to assess the effect of possible exposure to THROMBIN-JMI on activated partial thromboplastin time (aPTT) at 48 hours post-surgery in subjects with likelihood of prior exposure to THROMBIN-JMI within the past 4 years.6 Of the 554 subjects, 550 had undergone surgery and completed the study. A total of 384 subjects undergoing vascular surgeries, neurosurgeries and orthopedic surgeries were exposed to THROMBIN-JMI (5,000 to 20,000 IU).
In this study, the impact of exposure to THROMBIN-JMI in 78 subjects who were positive for anti-bovine thrombin (aBT) antibodies prior to surgery was compared with 140 subjects who did not have any aBT antibodies and were not exposed to THROMBIN-JMI. The study did not meet the pre-specified primary endpoint, a mean change from baseline in aPTT at 48 hours post-surgery. The study was not powered to detect coagulopathy related to an immune response after bovine thrombin use.
A post hoc analysis was performed in which subjects who underwent surgery were re-assigned to one of four exploratory cohorts based on the presence or absence of pre-surgery anti-bovine factor V/anti-bovine factor V active (aBV/Va) antibodies and whether or not they were administered THROMBIN-JMI during the study surgery. Non-inferiority (based on aPTT) was observed in these exploratory cohorts at all-time points of 48 hours, 4 weeks, and 8 weeks post-surgery.
For the primary study cohort (THROMBIN-JMI use in subjects with baseline positive aBT or positive aBV/Va), there was a higher incidence of seroconversion from anti human thrombin (aHT) negative at baseline to post-surgery positive compared to the primary reference cohort (no THROMBIN-JMI use in subjects with baseline negative aBT or negative aBV/Va). This difference was not present at 48 hours after surgery but was evident at 4 weeks and 8 weeks post-surgery. A similar immunological response with aBT and aBV/Va antibodies was observed following THROMBIN-JMI administration.
Secondary immune responses in patients treated with THROMBIN-JMI were evidenced by the generation of anti-bovine and anti-human thrombin and factor V/Va antibodies, consistent with known immunogenicity of topical bovine thrombin.