Sustained improvement in renal function with palopegteriparatide in adults with chronic hypoparathyroidism: 2-year results from the phase 3 PaTHway trial

This post hoc analysis examines the impact of palopegteriparatide on renal function in adults with chronic hypoparathyroidism through week 104 of PaTHway, a phase 3 trial with a randomized, double-blind, placebo-controlled 26-week period and ongoing 156-week open-label extension. Changes in renal function were assessed using eGFR. At week 104, 76 of 82 participants remained in the trial. Of those, 82% had normal albumin-adjusted serum calcium levels (2.07–2.64 mmol/L), 97% were independent from conventional therapy, and none required active vitamin D. Mean (SD) serum phosphate (1.1 (0.2) mmol/L) and albumin-adjusted calcium x phosphate product (2.5 (0.4) mmol 2 /L 2 ) were normal. At week 104, mean (SD) eGFR was 77.8 (14.8) mL/min/1.73m 2 . With palopegteriparatide treatment mean eGFR increased 8.9 (11.0) mL/min/1.73m 2 ( P <.0001) from baseline to week 52, which was sustained through week 104 (mean (SD) change from baseline 9.0 (10.3) mL/min/1.73 m 2 ( P < 0.0001)). By week 104, 61% and 44% of participants had an increase in eGFR of ≥ 5 mL/min/1.73 m 2 and ≥ 10 mL/min/1.73 m 2 , respectively. Palopegteriparatide normalized mean 24-hour urine calcium within 26 weeks, maintaining levels below 6.2 mmol/day through week 104 (4.0 (2.3) mmol/day). No cases of nephrolithiasis were reported with palopegteriparatide. Most TEAEs were mild or moderate; no new safety signals reported. These findings show sustained renal safety of palopegteriparatide and suggest that PTH replacement with palopegteriparatide and independence from conventional therapy may not only preserve but improve renal function in adults with chronic hypoparathyroidism.