Relationship between duration of teriparatide therapy and clinical outcomes in postmenopausal women with osteoporosis.

SUMMARY: The extent to which fracture protection and safety varies with increasing time on teriparatide [rhPTH(1-34)] therapy is a clinically relevant unanswered question. In postmenopausal women with osteoporosis, increased duration of teriparatide versus placebo treatment was associated with a progressive decrease in the rates of nonvertebral fragility fractures and back pain. INTRODUCTION: The impact of duration of teriparatide [rhPTH(1-34)] therapy on patient outcomes is a relevant unanswered question. METHODS: Postmenopausal women with osteoporosis were randomized to once-daily subcutaneous injection with placebo (N = 544), teriparatide 20 microg (TPTD20; N = 541), or teriparatide 40 microg (TPTD40; N = 552) plus calcium and vitamin D supplementation. The time to first nonvertebral fragility fracture and new or worsening back pain following treatment initiation was analyzed using Cox partial likelihood regression treating time on therapy as a linear, time-dependent covariate. RESULTS: Compared with placebo, the relative hazard for nonvertebral fragility fractures decreased by 7.3% for each additional month of TPTD20 [hazard ratio = 0.927, 95% CI (0.876 to 0.982), p = 0.009] and by 7.6% for each additional month of TPTD40 [hazard ratio = 0.924, 95% CI (0.871 to 0.981), p = 0.009]. Clinical vertebral fractures appeared to increase over time in the placebo group and occurred primarily in the first time interval in the teriparatide treatment groups. Compared with placebo, the relative hazard of back pain was decreased by 8.3% for each additional month of TPTD20 [hazard ratio = 0.920, 95% CI (0.902 to 0.939), p < 0.001] and 8.7% for each additional month of TPTD40 [hazard ratio = 0.917, 95% CI (0.898 to 0.935), p < 0.001]. CONCLUSIONS: These findings suggest increased nonvertebral fracture protection, reduced back pain, and reduced occurrence of side effects with longer duration of teriparatide therapy.

Effects of teriparatide on serum calcium in postmenopausal women with osteoporosis previously treated with raloxifene or alendronate.

UNLABELLED: The effect of teriparatide (20 microg/day) on serum calcium was examined in postmenopausal women previously treated with alendronate or raloxifene. Women previously treated with alendronate or raloxifene who added teriparatide or switched to teriparatide did not have clinically meaningful increases in mean predose serum calcium. INTRODUCTION: The effects of a 6-month treatment with teriparatide (20 microg/day; rhPTH(1-34), TPTD) on serum calcium (Ca) was examined in a prospective study of postmenopausal women previously treated with alendronate (70 mg/week or 10 mg/day [ALN] or raloxifene 60 mg/d [RLX]) for > or =18 months. METHODS: Women continued their usual ALN or RLX during a 2-month antiresorptive phase. Women previously treated with ALN were randomized to add TPTD (n = 52) or switch to TPTD (n = 50) and women previously treated with RLX were randomized to add TPTD (n = 47) or switch to TPTD (n = 49). All were to take at least 500 mg/day of elemental Ca and 400-800 IU/day of vitamin D. RESULTS: Predose mean serum Ca did not significantly change in groups adding TPTD to either RLX or ALN treatment. In patients who switched from RLX or ALN to TPTD, mean serum Ca increased by 0.05 mmol/L and 0.04 mmol/L respectively. Only 1 patient had the predefined calcium endpoint of serum calcium > 2.76 mmol/L (11 mg/dL) at more than one visit. CONCLUSIONS: Women previously treated with ALN or RLX who added TPTD or switched to TPTD did not have clinically meaningful increases in mean predose serum Ca.

Reduction in the risk of developing back pain persists at least 30 months after discontinuation of teriparatide treatment: a meta-analysis.

INTRODUCTION: Teriparatide [rhPTH (1-34)] reduces fracture risk, and in a published meta-analysis of clinical trials, teriparatide-treated patients had reduced incidence of back pain relative to placebo or to antiresorptive drugs. The aim of this study was to evaluate back pain in teriparatide-treated versus comparator-treated patients during an interval including controlled clinical trials plus 30 months of additional follow-up. METHODS: A meta-analysis of four completed randomized, double-blinded trials of teriparatide [rhPTH (1-34)] versus comparator was performed. A multivariate Cox proportional hazards model was used to assess the heterogeneity of results and to estimate the relative risk of back pain. RESULTS: Patients in the pooled teriparatide group had reduced risk for any back pain [relative risk, 0.73 (95% CI, 0.61-0.87)], moderate or severe back pain [0.72 (0.58-0.89)], and severe back pain [0.39 (0.25-0.61)] compared with pooled controls, from initiation of the study drug through the end of follow-up. Sensitivity analysis showed that the results were robust to the removal of each individual trial from the meta-analysis. Separate meta-analyses comparing teriparatide versus placebo or antiresorptive drugs gave similar results. CONCLUSIONS: Teriparatide-treated patients had a reduced incidence of back pain versus those receiving a comparator during an observation encompassing clinical trials plus 30 months of posttreatment observation.

Association of severe vertebral fractures with reduced quality of life: reduction in the incidence of severe vertebral fractures by teriparatide.

OBJECTIVE: The association between vertebral fracture severity and health-related quality of life (HRQOL) was investigated in a subset of patients in the Fracture Prevention Trial. We sought to determine whether vertebral fracture severity was associated with HRQOL scores, and if so, to determine the effects of teriparatide (recombinant human parathyroid hormone 1-34) on vertebral fracture grades that most strongly impact HRQOL in postmenopausal women with osteoporosis. METHODS: Vertebral fracture severity was assessed by the visual semiquantitative (SQ) method. A subset of 444 patients with a baseline radiograph completed the Osteoporosis Assessment Questionnaire. Baseline HRQOL scores were modeled as a function of maximum baseline vertebral fracture grade, while controlling for age, bone mineral density, body mass index, and back pain. RESULTS: The effect of baseline vertebral fracture grade on baseline HRQOL was statistically significant, while interactions between vertebral fracture grade and the other variables were not statistically significant. SQ grade 3 (SQ3) vertebral fractures were associated with a significantly lower overall HRQOL score and with significantly lower physical function, symptoms, and emotional status dimension scores. After a median of 19 months of therapy, new or worsening SQ3 vertebral fractures occurred in 21 of 448 patients (4.7%) in the placebo group compared with 3 of 444 patients (0.7%) in the 20 mug/day teriparatide group. The risk of developing a new or worsened SQ3 vertebral fracture was reduced by 86% (P < 0.001) in patients treated with 20 mug/day teriparatide. CONCLUSION: Compared with prevalent fractures of lesser severity, SQ3 vertebral fractures were associated with reduced HRQOL. Teriparatide treatment significantly reduced the risk of new or worsening SQ3 vertebral fractures. These findings suggest, but do not directly demonstrate, a benefit of teriparatide on HRQOL.