Is teriparatide linked to osteosarcoma? A disproportionality analysis of the FAERS database

Abstract Background Teriparatide is approved for the treatment of osteoporosis and is generally well-tolerated. However, concerns remain about a possible association with osteosarcoma, a rare but aggressive bone malignancy. This pharmacovigilance study aims to evaluate the reporting frequency of osteosarcoma associated with teriparatide in the Food and Drug Administration Adverse Event Reporting System (FAERS). Methods Individual case safety reports (ICSRs) listing teriparatide as a suspected drug and osteosarcoma as an adverse event were extracted from the FAERS public dashboard up to 20 February 2025. Both descriptive and disproportionality analyses were performed. Results A total of 112,798 ICSRs involving teriparatide were retrieved, of which 29 were reported. Most cases involved female patients (72.4%) and older patients (48.3%). Almost all reports (96.6%) were classified as serious, with death being the most common outcome (44.8%). Of the reports with information on concomitant medications, 31% included five or more medications, with vitamins being the most common. The disproportionality analysis showed a significantly higher reporting frequency of osteosarcoma with teriparatide compared to all other drugs (reporting odds ratio, ROR: 15.31; 95% CI: 10.53–22.26). This signal remained consistent when the analysis was restricted to reports submitted since 2006 (ROR: 15.88; 95% CI: 10.92–23.09). The information component (IC) analysis confirmed this finding (IC: 3.56; 95% CI: 2.95–4), and similar results were observed for the post-2006 subset (IC: 3.60; 95% CI: 2.99–4.05). However, the analysis compared to another osteoporosis drug (romosozumab) did not confirm any safety signal for teriparatide. Conclusions This study highlights a disproportionate signal between teriparatide use and osteosarcoma when compared to all other drugs but not compared to romosozumab. Based on this and considering that previous evidence did not support an increased risk, further research is warranted to better understand this association.