Switch From rhPTH1-84 to TransCon PTH With Individual Dose Adjustment in Adult Hypoparathyroidism-4-Week Results

Area of Science:

• Endocrinology
• Pharmacology

Background:

• Chronic hypoparathyroidism (HypoPT) is treated with recombinant human PTH (rhPTH1-84).
• Palopegteriparatide (TransCon PTH), a novel long-acting PTH1-34 drug, is now approved for HypoPT treatment.
• No prior data existed on switching from rhPTH1-84 to TransCon PTH.

Purpose of the Study:

• To report the first clinical data on treatment switch from rhPTH1-84 to TransCon PTH.
• To evaluate dose adjustments and outcomes in HypoPT patients switching therapies.

Main Methods:

• Retrospective analysis of clinical data from 40 HypoPT patients switching from rhPTH1-84 to TransCon PTH.
• Standard initial dose of 18 µg TransCon PTH was used, irrespective of prior rhPTH1-84 dose.
• Documented dose adjustments, additional medications, and adverse events.

Main Results:

• 80% of patients required TransCon PTH dose adjustments within the first month to achieve normocalcemia.
• Dose reductions (9-15 µg) occurred in 38%, while increases (21-27 µg) were needed in 43%.
• Prior rhPTH1-84 dose significantly correlated with the adjusted TransCon PTH dose (r=0.4, P=.01).

Conclusions:

• This study provides the first clinical insights into switching from rhPTH1-84 to TransCon PTH.
• Data suggest that the starting TransCon PTH dose should be adapted based on the previous rhPTH1-84 dosage.
• Treatment switch was associated with mild to moderate adverse events in 60% of patients.