Efficacy and Safety of the Biosimilar Recombinant Human Parathyroid Hormone Cinnopar® in Postmenopausal Osteoporotic Women: A Randomized Double-blind Clinical Trial

Background: Due to high cost and burden of osteoporosis, it is reasonable to focus on the reduction of fractures as the main goal of treatment. We compared the efficacy and safety of a new biosimilar recombinant human parathyroid hormone (CinnoPar (R), CinnaGen, Iran) to the reference product (Forteo (R), Eli Lilly, USA) in a randomized double-blind clinical trial (RCT). Methods: Overall, 104 osteoporotic postmenopausal women aged 45-75 yr were randomized to receive 20 mu g daily subcutaneous injections of either Forteo (R) or CinnoPar (R) for 6-months from 2011-2012. Bone biomarkers were measured at baseline, and during first, third, and sixth month's follow-up along with lumbar spine, total hip, and femoral neck bone mineral density (BALD) assessment at the baseline and six months after that. The study was registered in Iranian registry of clinical trials under the registration number of IRCT138810121414N5. The endpoints were to compare bone biomarkets, BALD and drug safety between groups. Data analysis was performed using SPSS 11. Results: Age range of ninety-four patients who completed the study was 42-81 yr. Participants were divided into Forteo (45 subjects) and CinnoPar (49 subjects) groups. No significant difference in terms of bone biomarkers or BALD scores was shown between groups (P >= 0.05). The most prevalent side effects were hypercalcemia and hypercalciuria without any significant statistical differences between groups. Conclusion: CinnoPar (R) can be considered as a good alternative therapy for Forteo (R) in postmenopausal osteoporotic women due to its comparable efficacy and safety properties.