Administration of teriparatide for four years cyclically compared to two years daily in treatment Naïve and alendronate treated women

Abstract Purpose We evaluated if equivalent doses of TPTD given cyclically over 4-years could increase BMD >2-years of daily TPTD in 2 cohorts of women; previously untreated (Rx-Naive) and women previously treated with ALN (ALN-Rx). Methods In Rx-Naive, women were randomized to daily TPTD for 24 months (Daily; n = 23) or cyclic TPTD for 48 months (3 months on, 3 months off; Cyclic; n = 25). In ALN-Rx, women were randomized to continued ALN plus daily TPTD for 24 months, followed by ALN alone for 24 months (Daily; n = 21) or TPTD for 48 months (3 months on, 3 months off) while ALN was continued (Cyclic; n = 20). BMD (DXA) was measured at spine (LS), total hip (TH) and femoral neck (FN). The primary analysis compared 4 years of cyclic therapy to 2 years of daily therapy in RX-naive and ALN-RX cohorts. Results In Rx-Naive, BMD changes at 24 months after Daily TPTD vs. 48 months after Cyclic TPTD were: LS 8.6% vs. 6.9%; TH 2.5% vs. 2.6%, and FN 1.6% vs. 2.2%. None of the BMD changes differed significantly between groups but all changes were significant over time within each group (p  Conclusion The same cumulative dose of TPTD given cyclically for 4-years, does not increase BMD more than standard daily TPTD over 2-years in either Rx-Naive or ALN-Rx women. Trial Registration: NCT00668941