[Different Perspectives of Drug Holiday and Combination Therapies When Treating Osteoporosis].

Different Perspectives of Drug Holiday and Combination Therapies When Treating Osteoporosis Sequential and combined therapy for osteoporosis is challenging because of the many options, and difficult because robust fracture data are not available, especially for combination therapies, mostly because the studies are too small. The principle of sequential and combined therapy for osteoporosis is that osteoanabolic therapy (teriparatide [TPTD]), whether sequential or combined, leads to an increase in bone mineral density (BMD), especially in the lumbar spine. The only exception is the sequence of TPTD after denosumab (Dmab), which leads to a loss (transient) of BMD in both the lumbar spine and the hip; for this reason, this sequence should be avoided at all costs. A second principle is that the stronger and longer the antiresorptive pretreatment was, the more delayed and reduced the effect of osteoanabolic therapy (TPTD). A third principle is the need for antiresorptive retreatment after therapies with TPTD and Dmab or their combination to prevent vertebral fractures (Dmab) and maintain bone density (TPTD). An effect of osteoanabolic therapy with TPTD on BMD of the hip is expected only in combination with antiresorptive therapy (bisphosphonates, Dmab). If the antiresorptive therapy is not continued, there is a transient loss in the first months of osteoanabolic monotherapy, the more so the stronger the antiresorptive pretreatment was.