CLINICAL PHARMACOKINETICS OF FERRIC NATURAL PROTEIN IN IRON-DEFICIENTFEMALES

Although iron therapy is very common, few studies have assessed iron a bsorption or iron kinetics in general, particularly with Fe3+. This wa s the primary objective of this study, with assessment of tolerance as a secondary objective. Eight nonsmoking iron-deficient females withou t other associated pathologies, with an average age of 21.62 +/- 1.69 years, were studied. The diagnosis of iron deficiency was established by determination of sideraemia (28.7 +/- 13.5 mu g/dl), iron binding c apacity (380.5 +/- 70.2 mu g/dl) and ferritin (5 +/- 1.4 mu g/L) on th e prestudy visit. The women remained in the Phase I Unit during days 0 , 1, 2 and 3 of the study. A serum iron concentration curve was obtain ed daily from blood samples drawn at 0, 1, 2, 4, 6, 8 and 12 hours pos tdose. Therapy with ferric natural protein (ferrimannitol ovoalbumin) 40mg twice daily was started on day 1 of the study and continued for 3 0 days. The following parameters were evaluated: area under the curve (AUC(0-12h)), peak iron concentration (C-max) and time to reach peak c oncentration (t(max)). Serum iron concentration-time curves were pract ically flat on day 0, but showed an increase following ferric therapy (Friedman, p < 0.05); confirming the usefulness of the postabsorption test and goad absorption of ferric iron (Fe3+). The increase in AUC (3 14.65 +/- 67.9 to 1174.44 +/- 1071.8 mu g/dl.h) and C-max (49 +/- 24.4 to 146 +/- 101.9 mu g/dl) from day 1 and the correlation between both parameters (r(2) > 0.85, p less than or equal to 0.008) supported the use of either parameter. The t(max) ranged from 4 to 6 hours. Ferric therapy was well tolerated by all patients. This study shows that ferr ic iron contained in this preparation is well absorbed and provides a satisfactory method for evaluation of iron absorption.