26-26-26-27-27-27-hexafluoro-1-25-dihydroxyvitamin-d3 and Kidney-Failure--Chronic

The 26 and 27 positions of vitamin D molecular structure of calcitriol were fluorinated with 3 atoms of fluorine each and the new compound was named falecalcitriol (F6). This new compound was found to be 10 to 100 times more active compared with calcitriol depending on the target organs. As a mechanism of strong action of F6 it was discovered that F6 is hydroxylated at 23 position which has almost the same activity as the mother compound. It was also demonstrated that the PTH suppressive effect was relatively stronger than the calcium absorption action from the intestine. Thus F6 was authorized to be applied to the treatment of secondary hyperparathyoroidism in hemodialysed patients as well as to the treatment of hypoparathyroidism.

Topics: Animals; Bone Remodeling; Calcitriol; Calcium; Humans; Hyperparathyroidism, Secondary; Kidney Failure, Chronic; Parathyroid Hormone; Renal Dialysis

Topics: Calcitriol; Cholecalciferol; Drug Design; Ergocalciferols; Humans; Hydroxycholecalciferols; Hyperparathyroidism, Secondary; Kidney Failure, Chronic; Vitamin D

Much effort has been made to create highly potentiated active vitamin D for better clinical applications and falecalcitriol was successfully synthesized as one of such candidates with highly potent and long-lasting effects. Its chemical structure has a calcitriol side chain modification in which both methyls at positions C-26 and C-27 are substituted by tri-fluoromethyls. The mechanism for its strong and long-lasting effects is probably due to altered side chain metabolism and decreased inactivation. Although C-24 position hydroxylation catalyzed by Cyp24 inactivates calcitriol, falecarcitriol is metabolized to C-23S hydroxylated metabolite by the same enzyme Cyp24 and this metabolite still has strong activity. Stronger action of falecalcitriol has been shown in target organs or cells of active vitamin D such as bone, parathyroid cells, and keratinocytes, when compared with calcitriol, the endogenous active form of vitamin D. Daily oral administration of falecalcitriol at doses lower than those required for calcitriol has been shown to have clinical effects for the treatment of diseases such as hyperparathyroidism due to chronic renal failure (2 degrees HPT), rickets, osteomalacia and hypoparathyroidism. The comparative study with alfacalcidol showed its specific action on parathyroid hormone suppression and better improvement of bone metabolism markers in 2 degrees HPT patients.

Topics: Animals; Bone and Bones; Calcitriol; Cell Division; Clinical Trials as Topic; Dose-Response Relationship, Drug; Humans; Hyperparathyroidism, Secondary; Hypoparathyroidism; Keratinocytes; Kidney Failure, Chronic; Osteomalacia; Parathyroid Glands; Parathyroid Hormone; Rickets; Structure-Activity Relationship

Falecalcitriol is a novel vitamin D analog, which has a greater potential to suppress parathyroid hormone (PTH) and a longer half-life. There are few studies to compare clinical effects of oral falecalcitriol treatment with those of intravenous calcitriol treatment.. Twenty-one patients with moderate to severe SHPT were included in a random 2 x 2 crossover trial with the two vitamin D analogs (12 weeks for each treatment). The primary endpoint measure was a decrease in serum intact PTH (iPTH) level, and the secondary outcome measures included changes in serum calcium (Ca), phosphate (P), and metabolic bone marker levels.. Both treatments decreased iPTH and whole PTH (wPTH) levels by similar degrees (iPTH, -200.1 +/- 107.0 with falecalcitriol vs. -200.8 +/- 114.9 pg/ml with calcitriol, p = 0.9895; wPTH, -137.1 +/- 73.1 with falecalcitriol vs. -120.4 +/- 81.1 pg/ml with calcitriol, p = 0.5603). Serum Ca, P, and Ca x P product levels at the end of each treatment were comparable and the frequencies of hypercalcemia and hyperphosphatemia were also similar during each treatment period. Although intravenous calcitriol treatment significantly changed intact osteocalcin and cross-linked N-telopeptide of type I collagen after 12 weeks, oral falecalcitriol treatment did not change any bone metabolic marker level.. The present study showed that oral falecalcitriol treatment is effective for PTH suppression, and Ca and P metabolism in hemodialysis patients with moderate to severe SHPT, as well as intravenous calcitriol administration.

Topics: Administration, Oral; Alkaline Phosphatase; Biomarkers; Bone and Bones; Bone Density Conservation Agents; Calcitriol; Calcium; Collagen Type I; Cross-Over Studies; Female; Humans; Hyperparathyroidism, Secondary; Injections, Intravenous; Kidney Failure, Chronic; Male; Middle Aged; Osteocalcin; Parathyroid Hormone; Peptides; Phosphorus; Renal Dialysis; Treatment Outcome

Alfacarcidol and calcitriol are widely used to treat secondary hyperparathyroidism associated with chronic renal failure, but it is often not possible to administer doses high enough to sufficiently inhibit parathyroid hormones because of the risk of hypercalcemia and hyperphosphatemia. We administered falecalcitriol (Hornel) Tablets) to patients with poorly controlled secondary hyperparathyroidism. The usefulness of falecalcitriol was demonstrated by the fact that control of intact-PTH was maintained for up to 24 months without a clear increase in serum Ca x serum inorganic phosphorus (iP), iP, and ALP levels.

Topics: Aged; Calcitriol; Depression, Chemical; Female; Humans; Hyperparathyroidism, Secondary; Kidney Failure, Chronic; Male; Middle Aged; Parathyroid Hormone; Renal Dialysis; Time Factors

Anemia is an important prognostic factor in hemodialysis patients. It has been reported that parathyroidectomy ameliorates anemia and reduces the requirement of postoperative erythropoiesis-stimulating agents. The objective of this study was to assess the effect of cinacalcet, which is considered as a pharmacological parathyroidectomy, on anemia in hemodialysis patients.. We used data from a prospective cohort of Japanese hemodialysis patients with secondary hyperparathyroidism; the criteria were: intact parathyroid hormone concentrations ≥ 180 pg/mL or use of an intravenous or oral vitamin D receptor activator. All patients were cinacalcet-naïve at study enrollment. The main outcome measure was achievement of the target hemoglobin level (≥10.0 g/dL), which was measured repeatedly every 6 months. Cinacalcet exposure was defined as cumulative time since initiation. Both conventional longitudinal models and marginal structural models were adjusted for confounding factors.. Among 3,201 cinacalcet-naïve individuals at baseline, cinacalcet was initiated in 1,337 individuals during the follow up. Cinacalcet users were slightly younger; included more patients with chronic glomerulonephritis and fewer with diabetes; were more likely to have a history of parathyroidectomy; and were more often on activated vitamin D agents, phosphate binders, and iron supplements. After adjusting for both time-invariant and time-varying potential confounders, including demographics, comorbidities, comedications, and laboratory values, each additional 6-month duration on cinacalcet was associated with a 1.1-fold increase in the odds of achieving the target hemoglobin level.. Cinacalcet may improve anemia in chronic hemodialysis patients with secondary hyperparathyroidism, possibly through pathways both within and outside the parathyroid hormone pathways. Further investigations are warranted to delineate the roles of cinacalcet not only in the management of chronic kidney disease-mineral and bone disorder but also in anemia control.

Topics: Aged; Anemia; Calcimimetic Agents; Calcitriol; Case-Control Studies; Cinacalcet; Diabetes Complications; Female; Follow-Up Studies; Glomerulonephritis; Hemoglobins; Humans; Hyperparathyroidism, Secondary; Kidney Failure, Chronic; Male; Middle Aged; Odds Ratio; Parathyroid Hormone; Prospective Studies; Receptors, Calcitriol; Renal Dialysis; Treatment Outcome

Topics: Calcitriol; Drug Resistance; Humans; Hyperparathyroidism, Secondary; Kidney Failure, Chronic; Male; Middle Aged; Peritoneal Dialysis, Continuous Ambulatory; Vitamin D