Objective: To compare the clinical efficacy and safety between recombinant human parathyroid hormone (rhPTH) (1-34) and elcatonin in the treatment of postmenopausal women with osteoporosis in China.
Methods: This 6 month, multicenter, randomized and controlled study enrolled 205 postmenopausal women with osteoporosis. They were randomized to receive either rhPTH (1-34) 20 µg (200 U) daily or elcatonin 20 U weekly. Lumbar spine (L1-4) and femoral neck bone mineral density (BMD) and biochemical markers of bone turnover were measured. In the meantime adverse events were recorded.
Results: The results showed that both rhPTH (1-34) and elcatonin increased L1-4 BMD significantly at the endpoint of the study, but femoral neck BMD did not change significantly. From baseline to endpoint, BMD of L1-4 and femoral neck in the rhPTH (1-34) group increased by 5.51% (P<0.01) and 0.65% (P>0.05), but BMD of L1-4 and femoral neck in elcatonin group increased by 1.55% (P<0.05) and 0.11% (P>0.05). Moreover, the rhPTH (1-34) group had better improvement in L1-4 BMD than the elcatonin group at 3, 6 months, but there was no difference of BMD in these two groups with regard to femoral neck. There were greater mean increases of the bone markers in the rhPTH (1-34) group than those in the elcatonin group at 3, 6 months [serum bone-specific alkaline phosphatase (BSAP) 36.79% vs 0.31%; 92.42% vs -0.17%; the ratio of urine N-telopeptide of type I collagen and creatinine (NTX/Cr) 48.91% vs -5.32%; 68.82% vs -10.86%]. Both kinds of treatment were well tolerated and there were no differences between the two groups in the rates of adverse events and serious adverse events.
Conclusion: It is concluded that rhPTH (1-34) has more positive effects on bone formation than elcatonin as shown by the greater increments of L1-4 BMD and bone formation markers and the less occurrence of adverse events as well as no significant change in hepatic, renal or hemopoietic function.