Task: Answer Verification
Input (English): Question: Does the ABCG2 C421A polymorphism affect oral nitrofurantoin pharmacokinetics in healthy Chinese male subjects?
Answer: The ABCG2 C421A polymorphism had no effect on nitrofurantoin plasma and urine pharmacokinetic parameters in healthy Chinese subjects. These results indicate that nitrofurantoin is not a suitable clinical probe substrate for assessing BCRP activity.
Output (English): no