Comparison of biologic porcine secretin, synthetic porcine secretin, and synthetic human secretin in pancreatic function testing

Background and Aims: Due to the unavailability of biologic porcine secretin (BPS), 2 synthetic forms of secretin were developed. Our aim is to determine the bioequivalency of the 3 forms of secretin in pancreatic function testing. Methods: In a randomized, crossover design, synthetic porcine (SPS) and synthetic human secretin (SHS) were compared in a group of 12 subjects with chronic pancreatitis undergoing secretin stimulation test (SST). The 2 synthetic forms of secretin were then compared with BPS in 12 subjects utilizing a similar design. Finally, 18 healthy subjects underwent secretin stimulation testing with SHS. Results: There was excellent correlation of peak bicarbonate measurements in the comparison of SPS to SHS (R = 0.967) as well as in the comparison of all 3 forms of secretin (P = 0.08, ANOVA for correlated samples). In the SST, each of the synthetic forms of secretin were 100% accurate in diagnosing chronic pancreatitis in disease subjects and in excluding chronic pancreatitis in normal controls. The synthetic forms of secretin were associated with fewer side effects when compared with BPS with the exception of transient tachycardia which occurred in up to 19% of subjects. Conclusions: The synthetic porcine and human forms of secretin are equivalent to one another and to biologic porcine secretin and can be used interchangeably in pancreatic function testing.