A new study on teriparatide (a PTH analogue) and alendronate brings again to clinical attention the issue of combination therapies for osteoporosis. The study by Finkelstein and colleagues  randomized 93 postmenopausal women with low bone mineral density (BMD) to either teriparatide 40 μg subcutaneously daily, or alendronate 10 mg daily, or both for 30 months. Teriparatide was begun at month 6 (thus treatment lasted 24 months according to the approved duration by the FDA). The mean age at baseline was around 63 years, and the mean lumbar spine and femoral T-score was around -2 standard deviations. The spine BMD increased by 6.8 ± 4% in women treated with alendronate, by 17.8 ± 11% in women treated with teriparatide, and by 11.9 ± 9% in women treated with both medications. The corresponding percentages for the femoral neck were 3.5 ± 4%, 10.8 ± 5% and 3.1 ± 5%, respectively. Levels of serum osteocalcin and N-terminal propeptide of type 1 collagen (P1NP) (both markers of bone formation) and N telopeptide (a marker of bone resorption) were measured as well. Osteocalcin and P1NP declined from baseline to month 6 and then stabilized, whereas N telopeptide reached its nadir within 1–2 months in the alendronate group. In the teriparatide group, all bone markers reached peak values 6 months after start of treatment, and then gradually declined. During the combined treatment, osteocalcin and P1NP rose steeply during the first 6 months and continued to increase throughout the study period, but the increase in N telopeptide was more gradual and more modest.
Department of Medicine T, Ichilov Hospital, Tel-Aviv, Israel
Finkelstein JS, Wyland JJ, Lee H, Neer RM. Effects of teriparatide, alendronate, or both in women with postmenopausal osteoporosis. J Clin Endocrinol Metab 2010; Feb 17. Epub ahead of print.
Tseng LN, Sheu WH, Ho ES, et al. Effects of alendronate combined with hormone replacement therapy on osteoporotic postmenopausal Chinese women. Metabolism 2006;55:741-7.
Johnell O, Scheele WH, Lu Y, et al. Additive effects of raloxifene and alendronate on bone density and biochemical markers of bone remodeling in postmenopausal women with osteoporosis. J Clin Endocrinol Metab 2002;87:985-92.
Fadanelli ME, Bone HG. Combining bisphosphonates with hormone therapy for postmenopausal osteoporosis. Treat Endocrinol 2004;3:361-9.
Ste-Marie LG, Schwartz SL, Hossain A, et al. Effect of teriparatide [rhPTH(1-34)] on BMD when given to postmenopausal women receiving hormone replacement therapy. J Bone Miner Res 2006;21:283-91.