A pilot study of oral calcitriol (1,25-dihydroxyvitamin D3) for relapsing-remitting multiple sclerosis.
BACKGROUND
Epidemiological and ecological studies suggest links between vitamin D deficiency and increased multiple sclerosis (MS) prevalence.


OBJECTIVE
To evaluate the safety and tolerability of oral calcitriol therapy in an open label pilot study.


METHODS
15 ambulatory patients with relapsing-remitting MS and at least one clinical relapse within the previous 12 months received oral calcitriol (target dose: 2.5 microg/d) for 48 weeks. Dietary calcium was restricted to 800 mg/d. Patients were monitored using frequent clinical and laboratory examinations, the expanded disability status scale (EDSS), and brain magnetic resonance imaging (MRI).


RESULTS
Two patients withdrew because of symptomatic hypercalcaemia (serum calcium >3.35 mmol/l in each case) resulting from persistent dietary indiscretion. Two diet compliant patients required temporary dose adjustments for mild asymptomatic hypercalcaemia. Diet compliant patients experienced mild adverse effects. The on-study exacerbation rate (27%) was less than baseline. Four patients experienced five clinical relapses but only one patient worsened by >1 EDSS point. Brain MRI revealed enhancing lesions in five patients at baseline (33%) and in four (29%) at both 24 and 48 weeks.


CONCLUSIONS
Oral calcitriol is safe and well tolerated for up to one year by diet compliant relapsing-remitting MS patients. Further study of vitamin D related mechanisms is warranted in MS.
Wingerchuk
D M
DM
Mayo Clinic, Scottsdale, Arizona, USA. wingerchuk.dean@mayo.edu
Lesaux
J
J
Rice
G P A
GP
Kremenchutzky
M
M
Ebers
G C
GC
D000284:Administration, Oral; D000328:Adult; D002117:Calcitriol / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D002120:Calcium Channel Agonists / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D009103:Multiple Sclerosis / Q000188:drug therapy* / Q000473:pathology*; D010507:Periodicity; D012008:Recurrence; D012720:Severity of Illness Index
D002120:Calcium Channel Agonists; D002117:Calcitriol