[Expert Solution]: A patient in a clinical trial was given a 500…

A patient in a clinical trial was given a 500 mg dose of the experimental drug, UA24337, orally every 8 hr for three days and plasma concentrations were measured every hour throughout. The bioavailability of this drug was known to be 100%. Previous studies had indicated that the optimum therapeutic plasma concentration of UA24337 was 25 mg/L, and adverse effects (not life-threatening) were generally seen only when plasma concentrations exceeded 40 mg/L. In this first trial, the plasma concentrations were generally in the therapeutic range and no adverse effects were noted. The next week the same patient returned for a second trial and was given the same dose of drug using the same dosing scheme. However, this time, obvious adverse effects were reported after the 4th dose. On discussing this with the patient, it was determined that the only difference between the two weeks was the juice that the patient drank regularly. The first week they had apple juice on a regular basis, while the second week they had grapefruit juice at least three times a day (strange but true…). A. From the plasma concentration profiles provided, construct the appropriate graphs and calculate the ke, Vd, CL, %PTF, Cmaxss, Cminss, and Css for each of the trials. (7 marks) B. Discuss how grapefruit juice is impacting the pharmacokinetics and explain the underlying mechanisms involved (requires search of primary literature). (4 marks) C. How would you modify the dosage and/or dosing interval to compensate for the effect of grapefruit juice on the drug’s pharmacokinetics and achieve a similar CSS and %PTF as that seen in the first week’s trial? Explain your rationale. (4 marks)