Highlights

  • Ascendis reports significant eGFR improvements from Week 26 through trial completion.
  • Mean eGFR increased 9.6 mL/min/1.73 m² by Week 52.
  • Nearly 69% of patients achieved clinically meaningful eGFR gains by Week 52.
  • Most patients ended treatment independent of active vitamin D and therapeutic calcium.

Ascendis Pharma A/S (NASDAQ:ASND) has released pooled kidney function data from its Phase 2 PaTH Forward and Phase 3 PaTHway studies of TransCon PTH, also known as palopegteriparatide. The analysis describes early improvements in adults with hypoparathyroidism that were sustained during treatment lasting up to five years. The findings were presented at Kidney Week 2026.

Early Gains Remain Visible Over Time

Across patients receiving treatment, estimated glomerular filtration rate, or eGFR, improved significantly from Week 26 through trial completion. Mean eGFR increased by 7.2 mL/min/1.73 m² at Week 26 and by 9.6 at Week 52. At the one-year mark, 68.9% of patients recorded an increase of at least 5 mL/min/1.73 m², while 49.6% achieved an increase greater than 10. From Week 52 to Week 266, the mean eGFR slope was 0.28 mL/min/1.73 m² per year.

Calcium Measures Add Another Dimension

The pooled analysis also tracked urinary and serum calcium. Mean 24-hour urine calcium fell from 396 mg per day at baseline to 206 mg at Week 26 and 170 mg at Week 52, with improvements sustained through trial completion. At the final visit, 98% of patients no longer used active vitamin D and 95% were independent of therapeutic calcium doses, defined as less than 600 mg per day. Normal albumin-adjusted serum calcium was recorded in 88% of patients at the final visit.

Study Population and Safety Findings

The two studies enrolled 141 adults, and the pooled kidney analysis included 139 patients who received at least one dose. Of these, 129 completed the final visit. The analysis was conducted post hoc and included randomized, double-blind periods followed by open-label extensions. TransCon PTH was generally well tolerated, with no new safety signals. Most treatment-emergent adverse events were mild or moderate.

Approved Therapy and Continuing Evidence

TransCon PTH is a once-daily prodrug designed to deliver active parathyroid hormone within the physiological range over 24 hours. It is approved as YORVIPATH for adults with hypoparathyroidism in the United States, European Union and other jurisdictions. The newly presented analysis adds longer-term kidney and calcium measurements to the clinical evidence, while its post-hoc design remains an important feature of the findings.