## Calculate the BE limits for HVDPs based on EMA [RSABE / ABEL]

Hi,

» I am so confused about how to calculate the suitable BE limits for HVDPs based on EMA criterion since the range changes all the time.
»
» When we get a CVwr, how to get the BE limits?

The easiest way is using R. Some nice guy in this forum wrote a package so basically
library(powerTOST) scABEL(CV, regulator)
will give you whatever you want, where CV is the CV of reference. And it's not limited to EMA. you can use it for calculations according to US FDA's and Canadian's guidance too (regulator="FDA" or "HC"). e.g.

scABEL(0.5, regulator="EMA") will give you
    lower     upper 0.6983678 1.4319102 

and scABEL(0.4, regulator="EMA")  will give
    lower     upper 0.746177 1.340165 

If you like to reinventing the wheel then it is also pretty straightforward to do so. If your CVWR is between 30% and 50%, the lower and upper limit is EXP(-0.76*sWR) and EXP(0.76*sWR), respectively.
Relatioship between CVWR and sWR is described in EMA's guideline. you can check the formula there.

All the best,
Shuanghe