Bioequivalence and Bioavailability Forum

Dear Ravi,

❝ My question is can we test for BE among T1, T2 and T3 using one of the test product as reference. When T1, T2 and T3 are available in dose strength 550mg, 850mg and 1150mg respectively. If yes please explain a bit about appropriate design to be used.

Still I don’t understand the rationale of the study. You said you wanted to compare all three tests vs. reference. So I assumed that

• your drug/formulation is not suitable for a BCS-based biowaiver (not Class I, modified release), and
  
• dose linearity is already known.

What’s the strength of the reference?
Why do you want to show BE between tests?
The design to be applied is straightforward – a 4-period 4-sequence Williams’ design (see this post). If you are not sure about PK linearity I would go with separate 2×2 studies. Imagine a situation where one of the three T/R-comparisons fails: You will have to submit the entire package to authorities, containing the first 4×4 study plus a repeated 2×2 of the failed formulation. Not so nice.