Using Romosozumab prior to Antiresorptive Medication tied to better BMD gains: Study

Prior studies of anabolic/antiresorptive treatment sequences indicate that using teriparatide first followed by an antiresorptive results in greater bone mineral density (BMD) gains, particularly at the total hip, vs using an antiresorptive first followed by teriparatide. Romosozumab (Romo) increases bone formation while decreasing bone resorption, significantly increasing BMD and reducing fracture risk within 1 year. Therefore, "Treatment sequence is important with romosozumab," said Felicia Cosman, M.D., professor of medicine at Columbia University College of Physicians and Surgeons in New York City.

Dr. Cosman and colleagues evaluated percentage change from baseline in BMD at the total hip and lumbar spine from four trials where patients received Romo prior to an antiresorptive (Phase 3 ARCH and Phase 3 FRAME or Romo following antiresorptive therapy (Phase 3 STRUCTURE and Phase 2. Percentage change from baseline BMD was assessed by either an ANCOVA (FRAME) or repeated measures (ARCH, STRUCTURE) model adjusting for baseline covariates, or as summary statistics.

The following results were noted-

a. Total hip BMD: In ARCH, BMD increased 6.2% with 1 year of Romo, and a total of 7.1% with the 2-year Romo/Aln sequence. In FRAME, patients gained 6.8% with 1 year of Romo and a total of 8.8% with the 2-year Romo/DMAb sequence. Patients in STRUCTURE, who were previously treated for ≥1 year with Aln, gained 2.9% with 1 year of Romo. In a Phase 2 study, following 1 year of DMAb, 1 year of Romo increased BMD by 0.9%, for a total gain of 3.8% with the 2-year DMAb/Romo sequence.

b. Lumbar Spine BMD: In ARCH, BMD increased 13.7% with 1 year of Romo, and a total of 15.2% with the 2-year Romo/Aln sequence; and in FRAME, patients gained 13.3% with 1 year of Romo and a total of 17.6% with the 2-year Romo/DMAb sequence. Patients in STRUCTURE (previously on Aln for ≥1 year) gained 9.8% with 1 year of Romo. In Phase 2 study (after 1 year of DMAb), 1 year of Romo increased BMD by 5.3%, for a total gain of 11.5% with the 2-year DMAb/Romo sequence.

Therefore, the authors concluded that "in patients treated with Aln or DMAb, the transition to Romo can improve BMD, though gains are not as large as those seen when Romo is used first. Since BMD on treatment is a strong surrogate for bone strength, our findings support the concept that high-risk patients should be offered treatment with Romo first, followed by a transition to a potent antiresorptive."