Teriparatide, the active fragment of human
parathyroid hormone (hPTH 1-34), is an anabolic agent for the treatment of
osteoporosis. Important questions remain regarding management strategy beyond the recommended 18- to 24-month course of
teriparatide treatment. We followed 21 men for up to 2 years after discontinuing
teriparatide. Twelve men (57%) chose treatment with
bisphosphonate immediately after
teriparatide withdrawal, while 9 (43%) opted for no pharmacologic agent. At the end of 1 year lumbar spine bone density increased an additional 5.1+/-1.0% in the
bisphosphonate group, while it declined by 3.7+/-1.7% in those on no medication (P<0.002). In six men who delayed initiation of
bisphosphonate until 1 year after
teriparatide withdrawal, their subsequent gains in the second year, 2.6+/-1.7%, still placed them below the peak gains they achieved on
teriparatide. In contrast, the 12 men who began
bisphosphonates immediately and continued treatment for the entire 2-year post-PTH period had continued gains at the lumbar spine, 8.9+/-1.5% above their post-PTH values (P=0.002). For the 4-year period, including 2 years of
teriparatide and 2 years of
bisphosphonate, the total gains at the lumbar spine were 23.6+/-2.9%. Men, who received
bisphosphonate in only the 2nd year post-
teriparatide, had cumulative gains of 11.1+/-3.4%. Three men who did not receive any
bisphosphonate at any time during the post-PTH period had cumulative gains of only 5.5+/-3.7%. These findings suggest that the use of
bisphosphonates following
teriparatide is an important component of any strategy utilizing this anabolic drug for
osteoporosis in men. The immediate use of
bisphosphonates after
teriparatide withdrawal may help to optimize gains in bone density at the lumbar spine.