Many of us have been exposed to advertising related to the bioavailability of generic and brand- name

Many of us have been exposed to advertising related to the €œbioavailability€ of generic and brand- name formulations of the same drug product. One way to compare the bioavailability of two formulations of a drug product is to compare areas under the concentration curve (AUC) for subjects treated with both formulations. For example, the shaded area in the figure represents the AUC for a patient treated with a single dose of a drug.

A three- period crossover design was used to compare the bioavailability of two brand name (A1 and A2) and one generic version (A3) of weight-reducing agents. Three sequences of administering the drugs were used in the study:
Sequence 1: A1, A2, A3
Sequence 2: A2, A3, A1
Sequence 3: A3, A1, A2 A random sample of five subjects was assigned to each of the three sequences. The AUCs for these 15 patients are shown here.

a. Plot the formulation means (AUCs) by period for each sequence.
b. Is there evidence of a period effect?
c. Do the formulations appear to differ relative to AUC?

Transcribed Image Text:

Drug concentration Cog/mL Time (h) 3-38 1 5 202 36 48 236442122948 6. 376336 4895535457 45325255854851 ri-2-08888 51 43735 21 .4 2 7 6 3 5 7 8 721 .4 .3 123451234512345 2