Maintenance Vitamin D Therapy for Secondary Hyperparathyroidism (2HPT)
Maintenance Vitamin D Therapy for Secondary Hyperparathyroidism (2HPT)
There are still no established protocols for maintenance therapy with intravenous or oral
 vitamin D preparations after the iPTH target has been achieved.

 Therefore, the present study compared the efficacy of two maintenance therapy protocols,
 i.e., oral administration of alfacalcidol (an oral vitamin D preparation) at a dose of 1.0
 ug/day (higher-dose group) or at a dose of 0.25 ug/day (lower-dose group), in patients with
 secondary hyperparathyroidism who responded to initial maxacalcitol therapy, resulting in the
 control of iPTH to < 150 pg/mL.
Chronic kidney disease (CKD) causes various bone mineral disorders, which have recently been
 named CKD mineral and bone disorder (CKD-MBD). CKD-MBD presents a spectrum of skeletal
 abnormalities ranging from high bone turnover state such as osteitis fibrosa, which is seen
 with SHPT, to states of low bone turnover, which includes osteomalacia and adynamic bone
 disease. This disease not only increases the risk of cardiovascular disease and mortality,
 but also increases the risk of fracture. Therefore, it is important to correct the serum
 inorganic phosphorus (Pi), calcium (Ca) and parathyroid hormone (PTH) levels in dialysis
 patients, to achieve both appropriate bone turnover and to improve mortality.

 The Kidney Disease Outcomes Quality Initiative (K/DOQI) guidelines recommend that the target
 range of iPTH level for vitamin D therapy should be set at 150-300 pg/mL. In Japan, the
 mortality risk was significantly lower in the group of patients with iPTH levels < 120 pg/mL
 than in the standard group set at 180 pg/mL < iPTH < 360 pg/mL, and lowest in the group of
 patients with 60 pg/mL < iPTH < 120 pg/mL . Based on these findings, Japanese guideline
 recommend that the target range of iPTH should be set at 60-180 pg/mL .

 The efficacies of various oral and intravenous vitamin D preparations for treating SHPT in
 hemodialysis patients have been reported. and oral or intravenous vitamin D pulse therapy has
 been clinically applied, especially for patients with severe SHPT.

 Up to now, the effectiveness of an oral daily alfacalcidol on SHPT has been confirmed at the
 dose of 0.25-0.5 μg /day (average 0.364μg /day), 0.5 μg /day, and 1.0 μg /day. The effective
 dose of OCT has also been verified, and furthermore, it has also been reported that
 intravenous vitamin D was more effective than oral vitamin D for suppressing PTH secretion.
 Accordingly, at present intravenous vitamin D therapy is the standard treatment for SHPT, and
 there are established protocols with regard to dosage and administration. However, no
 protocols have been established for maintenance therapy using intravenous or oral vitamin D
 preparations after the control of iPTH target range has been achieved.

 Therefore, the present study compared the efficacy of two maintenance therapy protocols for
 patients with SHPT who responded to initial OCT therapy, resulting in the control of iPTH to
 <150pg/mL. One was oral administration of alfacalcidol (an oral vitamin D preparation) at a
 dose of 1.0 μg/day (higher-dose group) and the other was at a dose of 0.25 μg/day (lower-dose
 group), both of which are clinically effective doses for HD patients with SHPT.
Inclusion Criteria:

 -  Clinical diagnosis of secondary hyperparathyroidism (iPTH >200 pg/mL to <500 pg/mL)

 -  Serum Ca < 11.0 mg/dL, and serum P < 7.0 mg/dL.

 -  At least one year of regular hemodialysis therapy

 Exclusion Criteria:

 -  Patients with a history of hypersensitivity to any ingredient of maxacalcitol

 -  Patients who had received parathyroidectomy