Efficacy
hypoparathyroidism, normocalcemia
HYPOPARATHYROIDISM
After 26 weeks of blinded treatment, 79% (48/61) of participants receiving TransCon PTH versus 5% (1/21) receiving placebo achieved the primary composite endpoint of independence from conventional therapy, with maintenance of normocalcemia without an increase in study drug dose in the final 4 weeks of the blinded period (Percentage of Participants Meeting the Composite Primary Endpoint at Week 26
Abbreviations: CI, confidence interval; PTH, parathyroid hormone.Cochran–Mantel–Haenszel test controlling for etiology of hypoparathyroidism (postsurgical versus nonsurgical).The normal range for albumin‐adjusted serum calcium is 8.3–10.6 mg/dL (2.07–2.64 mmol/L).Elemental calcium supplement dose with TransCon PTH treatment. Treatment with TransCon PTH resulted in a greater reduction in mean daily calcium dose than placebo as early as 4 weeks (Active vitamin D supplement dose with TransCon PTH treatment. Per trial protocol, all participants decreased their active vitamin D dose by 33% to 50% (eg, by skipping the second dose of the day if taking 2 times daily (BID), skipping the final dose of the day if taking 3 times daily (TID), or reducing a once‐daily dose of alfacalcidol ≥1.0 μg by 50% (≥0.5 μg) at the start of the blinded treatment period. Subsequent dose decreases or discontinuations were done according to a predefined protocol. Within 4 weeks, the majority of participants treated with TransCon PTH discontinued active vitamin D. Mean doses of active vitamin D supplements were calculated from actual micrograms prescribed and are not adjusted for relative potency of calcitriol versus alfacalcidol. The difference in least squares (LS) means between TransCon PTH and placebo groups was statistically significant at all time points (Albumin‐adjusted serum calcium with TransCon PTH treatment. In the TransCon PTH group, mean serum calcium values remained within the normal range at all study visits through week 26. Baseline mean serum calcium was 8.8 mg/dL (2.2 mmol/L) and 8.6 mg/dL (2.15 mmol/L) for TransCon PTH and placebo, respectively, and 8.9 mg/dL (2.22 mmol/L) and 8.2 mg/dL (2.05 mmol/L), respectively, at week 26. Normal range for serum calcium = 8.3–10.6 mg/dL (2.07–2.64 mmol/L).Baseline and Week 26 Serum Biochemistries in Participants Treated With TransCon PTH and PlaceboAbbreviation: eGFR, estimated glomerular filtration rate.Albumin‐adjusted serum calcium.
eGFR adjusted for body surface area.