(137) The Impact of the COVID lock-down on transitions from a once-monthly parenteral therapy for osteoporosis in the U.S. Medicare program

Publication Number: 473

Background: Shortly after the licensure of romosozumab (romo), a parenteral osteoporosis (OP) biologic approved in April 2019, the SARS-Cov-2 pandemic broke out. Given the requirement that patients receive romo once monthly from healthcare providers, the patterns of romo use during the pandemic have not been previously evaluated.

Objectives: To evaluate the impact of the pandemic on use of OP therapies following discontinuation of romosozumab.

Methods: Using Medicare data from 1/1/2017 to 12/31/2020, women age ≥65 years newly initiating romo between 4/1/2019 and 9/30/2020 were identified. “Discontinuation” was defined as failure to receive romo within 30 days after the expected date of the next romo administration. We select patients whose discontinuation date was before 9/30/2020 to ensure a 3-month follow-up. We identified the first OP medication within 3 months after the last administration date and grouped them as: oral bisphosphonates, zoledronic acid, PTH analogues, as well as romo. As the national emergency was declared on Mar. 13, 2020, April 1, 2020 was defined as the start of lockdown period as most US states had implemented lockdown in March. The use of OP medications after discontinuation before and after the lockdown was compared using a chi-squared test. Kaplan-Meier method was used to evaluate the difference in resuming OP medication pre and post lockdown.

Results: There were 6725 romo new users identified, among whom 2920 (43.2%) discontinued romo treatment before 12/31/2020. 1554 patients discontinued before lockdown, and 2,585 patients before 9/30/2020.
For patients who discontinued romo before lockdown, within 3 months after the discontinuation date, 30.4% resumed romo treatment (vs. 25.5% for those who discontinued romo after lockdown), 5.8% switched to denosumab (vs. 19.8%), 0.5% switched to zoledronic acid (vs. 2.7%), 3.5% switched to other OP treatment (vs. 4.4%), and 59.8% (vs. 47.6%) did not receive any above-mentioned OP treatment (pre and post lock-down comparison). The overall pre and post lock-down comparison p< 0.01. The mean interval [95% CI] from romo discontinuation to receiving any OP treatment within 3 month was 81.7 [80.8, 82.5] days and 74.8 [73.5, 76.2] days in the pre vs. post lockdown period, respectively (Peto’s test p< 0.01 comparing Kaplan-Meier curves).

Conclusions: Compared to the pre-lockdown period, patients who discontinued romo during the lockdown period were more likely to resume OP treatment, yet were more likely to switch to OP medications that require less frequent dosing (e.g. denosumab). Transitions to oral OP therapies were uncommon. These findings suggest the necessity of proactively addressing safety concerns for patients receiving frequently-administered treatments during the pandemic.