The effects of sequential therapy using anti-resorptive agents after administering once-weekly teriparatide or twice-weekly teriparatide

Introduction Studies launched in Japan on once-weekly teriparatide (1/W-TPTD) and twice-weekly teriparatide (2/W-TPTD) are limited. Therefore, we examined the effects of sequential therapy using anti-resorptive agents after administering 1/W-TPTD and 2/W-TPTD using dual-energy X-ray absorptiometry (DXA) and DXA-based 3D modeling. Materials and methods This was a multicenter retrospective study following a phase 3 clinical trial called the TWICE study. Two-year follow-up data were collected after administering 1/W-TPTD or 2/W-TPTD for 1 year (follow-up after the phase 3 clinical trial). Results 20 subjects in the group of pre-treatments with 1/W-TPTD followed by sequential administration of bisphosphonate or denosumab (1/W-TPTD [BP/denosumab]), and 22 in the group 2/W-TPTD (BP/denosumab) were included in the analysis of changes in the BMD by post-treatment. In the 1/W-TPTD (BP/denosumab) group, a significant increase in L2–4 BMD was observed. In the 2/W-TPTD (BP/denosumab) group, a significant increase in total hip, neck, and L2–4 BMD values was observed. Analysis by 3D-SHAPER revealed that both the 1/W-TPTD (BP/denosumab) and 2/W-TPTD (BP/denosumab) groups demonstrated significant increases in cortical sBMD and vBMD 2 years after the initiation of post-treatment. Conclusion In subjects who received 1/W-TPTD and 2/W-TPTD for about 1 year followed by sequential administration of BP or denosumab, significant improvements in BMD were continuously observed. Furthermore, significant improvements in cortical sBMD and vBMD were also demonstrated by analysis using 3D-SHAPER. Both 1/W-TPTD and 2/W-TPTD were effective in the treatment of osteoporosis by using anti-resorptive agents for sequential administration.