STANFORD, Calif. – Teriparatide (Forteo® ) is considered to be a promising new treatment for osteoporosis, but a new analysis suggests that this anabolic agent is not cost-effective when compared with the bisphosphonate alendronate (Fosamax®), Hau Liu, MD, a postdoctoral fellow at Stanford University's Center for Health Policy/Center for Primary Care and Outcomes Research in Stanford, California, and colleagues report in the June 12 issue of the Archives of Internal Medicine.1 Restricting teriparatide's use to high-risk patients could make this agent more cost-effective, the study suggested.

"Teriparatide costs over $6700 per year and alendronate costs about $900 per year, but if the price of teriparatide were reduced to about $3000 per year, it would become cost-effective," Dr. Liu told CIAOMed. "Teriparatide is cost-effective in women who are at exceptionally high risk for fracture, [and also] if short courses of the medication [are] as effective as longer courses of the medication found in clinical trials."

Arch Intern Med. 2006;166:1209-1217.
The researchers evaluated the cost-effectiveness of vitamin D or calcium supplementation (usual care) compared with 5 years of alendronate alone, 2 years of teriparatide alone, and 2 years of teriparatide therapy followed by 5 years of alendronate therapy (sequential therapy) in a hypothetical cohort of 200,000 white postmenopausal women with low bone density and prior vertebral fractures. The main outcome measure was cost per quality-adjusted life-year (QALY). Hypothetical patients were analyzed for treatment strategy chosen; number and type of preexisting fractures; death or survival during the simulation period; admittance (or not) to a nursing home; adverse reactions from treatment; and new fractures during the simulation period. Researchers also calculated the cost-effectiveness of each therapy in terms of the cost per QALY gained, as well as survival.

Alendronate is cost-effective

Alendronate treatment costs $11,600 per QALY compared with usual care, according to a base-case analysis, while sequential teriparatide/alendronate therapy costs $156,500 per QALY compared with alendronate, the study showed. Sequential teriparatide/alendronate therapy was less cost-effective than alendronate even if fractures were eliminated during the alendronate phase, Liu et al report.

Teriparatide alone costs $172,300 per QALY year compared with usual care. Despite its high cost, teriparatide alone did not produce health benefits as great as those of alendronate. 

"Teriparatide alone is not a rational choice, because it is more expensive and produces a smaller increase in QALYs compared with alendronate alone," the study authors write. This finding held even if teriparatide's efficacy lasted 15 years after treatment cessation, according to a sensitivity analysis.

However, teriparatide may be a reasonable option for patients who are unable to use alendronate, the researchers note.

Making sequential therapy cost-effective

The cost-effectiveness of sequential teriparatide/alendronate is consistently higher than that of alendronate alone, but it would fall below $50,000 per QALY if the price of teriparatide were reduced 60%, if teriparatide were used only by women with a femoral neck T-score of  –4.0, or if 6-month courses of teriparatide could provide the same fracture reduction efficacy as those reported in longer clinical trials, the study authors suggest.

Several new studies have advocated the benefits of sequential therapy with teriparatide followed by alendronate to build and then maintain new bone.

"Our findings suggest that teriparatide alone is unlikely to be cost-effective, and that sequential therapy is expensive but under certain situations may become cost-effective," Dr. Liu said. "More and more experts in the field advocate starting an anti-resorptive agent after completion of teriparatide, [and] our findings support this view in that the sequential strategy was always more cost-effective than the teriparatide-alone strategy."

Reference

  1. Liu H, Michaud K, Nayak S, et al. The cost-effectiveness of therapy with teriparatide and alendronate in women with severe osteoporosis  Arch Intern Med. 2006;166:1209-1217.