Successful transition from rhPTH(1-84) to palopegteriparatide in chronic hypoparathyroidism

Hypoparathyroidism management has advanced in recent decades, particularly for patients unresponsive to conventional therapy. Several parathyroid hormone-based agents have been developed to better imitate physiologic hormone replacement. Recombinant human parathyroid hormone (1-84) [rhPTH(1-84), Natpar®] was approved as an adjunct to calcium and vitamin D for chronic hypoparathyroidism but was later withdrawn, with global production ceasing in 2024. Palopegteriparatide (Yorvipath®; TransCon PTH), a long-acting parathyroid hormone (1-34) prodrug recently approved, represents a new-generation replacement therapy. Transitioning patients from rhPTH(1-84) to palopegteriparatide is increasingly relevant but remains scarcely documented, with only a single real-world report available. We describe a patient with chronic postsurgical hypoparathyroidism after total thyroidectomy who continued to experience symptoms despite conventional therapy. rhPTH(1-84) initially improved symptoms and stabilized calcium levels, but additional supplementation became necessary over time. In September 2024, ahead of rhPTH(1-84) withdrawal, therapy was switched to palopegteriparatide, allowing gradual dose titration and complete withdrawal of calcium and magnesium supplements. The patient maintained stable biochemical values and reported improved well-being, with no adverse events. This case supports the effective transition from rhPTH(1-84) to palopegteriparatide, restoring biochemical stability and independence from conventional therapy.