Continuous Subcutaneous Delivery of rhPTH(1-84) and rhPTH(1-34) by Pump in Adults With Hypoparathyroidism

Abstract

Context: Continuous subcutaneous infusion of recombinant parathyroid hormone (rhPTH) through a pump has been proposed as a therapeutic alternative for patients with chronic hypoparathyroidism who remain symptomatic or hypercalciuric on conventional treatment (calcium and active vitamin D) or daily injections of rhPTH(1-84) or rhPTH(1-34). However, the real-world evidence of the outcome of this novel therapy is limited.

Case descriptions: We report the clinical and biochemical outcomes of 12 adults with hypoparathyroidism (11 women, age 30-70 years, and 1 man, age 30 years) from 3 different clinical sites in the United States who were transitioned from conventional therapy to daily injections of rhPTH(1-84) or rhPTH(1-34) and then switched to continuous administration of rhPTH(1-84)/rhPTH(1-34) via pump therapy. In most patients, mean serum calcium concentrations increased while on PTH pump therapy compared with both conventional therapy (in 11 patients) and single/multiple daily rhPTH injections (in 8 patients). Despite this, 10 patients had lower median 24-hour urinary calcium levels while on PTH pump therapy compared with prior therapy (mean ± SD difference: -130 ± 222 mg/24 hours). All patients reported a qualitative decrease in hypocalcemic symptoms while receiving pump therapy. Three patients had pod failure at least once, and 1 patient developed an infusion site reaction.

Conclusion: In this case series of 12 patients with chronic hypoparathyroidism treated with rhPTH(1-84)/rhPTH(1-34) administered via a pump, improvement in clinical and biochemical parameters were observed in the majority of the patients. Our observations indicate benefits of pump administration of rhPTH that warrant further investigation.

Keywords: PTH pump; hypoparathyroidism; parathyroid hormone replacement therapy; recombinant human parathyroid hormone 1-34; recombinant human parathyroid hormone 1-84; teriparatide.

Figure 1.

Serum calcium (A) and 24-hour urine calcium (B) during different treatment periods. The white box indicates treatment with recombinant human parathyroid hormone 1-34. The gray box indicates treatment with recombinant human parathyroid 1-84 that was later transitioned to recombinant human parathyroid hormone 1-34. The rest are treatment with recombinant human parathyroid 1-84. Abbreviations: BID/TID, multiple daily parathyroid hormone injections; P, patient; Pre-PTH, conventional therapy (calcium and active vitamin D); pump, parathyroid hormone pump therapy; QD, single daily parathyroid hormone injection.

Figure 2.

Time-weighted percentage of different categories of albumin-corrected serum calcium concentrations during different treatment periods. The white box indicates treatment with recombinant human parathyroid hormone 1-34. The gray box indicates treatment with recombinant human parathyroid 1-84 that was later transitioned to recombinant human parathyroid hormone 1-34. The rest are treatment with recombinant human parathyroid 1-84. Abbreviations: BID/TID, multiple daily parathyroid hormone injections; Ca, calcium; P, patient; Pre-PTH, conventional therapy (calcium and active vitamin D); pump, parathyroid hormone pump therapy; QD, single daily parathyroid hormone injection.

Figure 3.

Time-weighted mean and SD of serum calcium concentration during different treatment periods. *, **, *** denote P < .05, P < .01, and P < .001, respectively.