Repaglinide (Prandin)
(Mercy Pharmacy Update, June 1998)
   The Committee approved repaglinide for the Hospital Formulary. It is the
first meglitinide compound to receive FDA approval for the treatment of Type 2
diabetes mellitus. Repaglinide is a nonsulfonylurea insulotropic agent that
reduces blood glucose levels by stimulating insulin release from the pancreas.
Repaglinide is rapidly absorbed with maximum concentrations occurring within 1
hour (Tmax) and is rapidly eliminated (T1/2 < 60 minutes). Postprandial plasma
insulk levels will increase in response to the mealtime glucose load and
return to basal levels before the next meal. The drug is most effective when
dosed three times daily before meals. The drug dosing allows patient
flexibility in the timing of meals. Repaglinide is metabolized to inactive
metabolites by the cytochrome P450 enzyme system (CYP 3A4) in the liver.
Tberefore, the metabolism of repaglinide may be inhibited by ketoconazole,
miconazole, and macrolide antibiotics. Agents that induce CYP 3A4 metabolism,
such as troglitazone (Rezulin), rifampin, or barbiturates may reduce
repaglinide levels and hypoglycomic response. Dosage adjustments are
recommended at 7-day intervals, while dosage adjustments in patients with
hepatic insufficiency require longer intervals. The hypoglycemic action of
repaglitude may be potentiated by agents that are highly protein bound, such
as, NSAIDs, salicylates, sulfonamides, warfarin.
   Repaglinide is approved for monotherapy and for use in combination therapy
with metformin (Glucophage). The recommended dosage range is 0.5-4 mg taken
2, 3, or 4 times daily according to the meal plan. The maximum daily dose is
16 mg. The starting dose for patients previously treated with sulfonylureas
and HgA1c, > 8 % is 1-2 mg taken before meals.
  Comparative Pharmacy Costs
  Prandin 2 mg tid ac #90 = $75.00*
  vs.
  Glynase 3 mg bid ac #60 = $40.00*
  vs.
  Glyburide (generic) 5 mg bid ac #60 = $27.50*
                                        $ 4.00**
* Average Wholesale Cost
**(AWP) Average Contract Cost