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Abstract: FR-PO972

Extended-Release Calcifediol: A Data Journey from Phase 3 Studies to Real-World Evidence Highlights the Importance of Early Treatment of Secondary Hyperparathyroidism (SHPT)

Session Information

Category: CKD (Non-Dialysis)

  • 2302 CKD (Non-Dialysis): Clinical, Outcomes, and Trials


  • Ashfaq, Akhtar, OPKO Health Inc, Miami, Florida, United States
  • Merante, Domenico, CSL Vifor, Zurich, Glattbrugg, Switzerland
  • Schou, Henrik, CSL Vifor, Zurich, Glattbrugg, Switzerland
  • Morin, Isabelle, CSL Vifor, Zurich, Glattbrugg, Switzerland
  • Manu, Marius Constantin, CSL Vifor, Zurich, Glattbrugg, Switzerland
  • Bishop, Charles W., OPKO Health Inc, Miami, Florida, United States
  • Strugnell, Stephen A., OPKO Health Inc, Miami, Florida, United States

Early secondary hyperparathyroidism (SHPT) diagnosis and treatment are crucial to delay the progression of SHPT and related complications, in particular, cardiovascular events and bone fractures. Extended-release calcifediol (ERC) has been developed for the treatment of SHPT in patients with stage 3 or 4 chronic kidney disease (CKD) and vitamin D insufficiency (VDI).


In this descriptive analysis, laboratory parameters of SHPT-CKD stage 3–4 subjects randomised to ERC in two phase 3 clinical studies (NCT01651000 [N=141] and NCT01704079 [N=144]) were compared with those treated with ERC in a RWE study (MBD-AWARE study; N=174]).


The main baseline laboratory parameters showed consistency between the phase 3 studies and the RWE study, except for baseline parathyroid hormone (PTH). Mean±standard deviation baseline PTH levels were 147±56 pg/mL and 148±64 pg/mL in the intent-to-treat populations on ERC in NCT01651000 and NCT01704079, respectively, and 181±98 pg/mL in the RWE study. Moreover, in the RWE study, 53% of subjects receiving ERC had CKD stage 4 with an even higher baseline PTH level versus stage 3 CKD subjects. ERC treatment significantly reduced PTH levels and increased 25-hydroxyvitamin D [25(OH)D], regardless of CKD stage, in all 3 studies. In the phase 3 per-protocol populations, 74% of subjects treated with ERC were up-titrated to 60 μg daily after 12 weeks at 30 μg daily, 97% attained 25(OH)D levels ≥30 ng/mL, and 40% achieved ≥30% reductions in PTH. In contrast, based on an apparent ‘wait longer approach’ to test key markers of SHPT, only 2% of subjects in the RWE study were up-titrated. Nevertheless, 70% of subjects achieved 25(OH)D levels ≥30 ng/mL, and 40% had a ≥30% reduction in PTH, consistent with the phase 3 results.


These data suggest a ‘continuum’ of clinical evidence of ERC effectiveness for treating SHPT, irrespective of CKD stage. A clinically relevant response was observed with ERC in the RWE study, consistent with the phase 3 studies, despite higher baseline PTH levels and lower ERC dose. In summary, these data support early treatment initiation with ERC, following diagnosis of SHPT, VDI and stage 3 CKD, to delay the progression of SHPT.


  • Commercial Support – CSL Vifor