Hi All,

Need some opinions on this topic:

I know when doing a drug vs tumor study in-vivo, it is the usual practice to use TGI or T/C ratio to "quantify" the effect of the drug on the tumor. However, there are some limitations to that.

When comparing between different lines, the end point for each line sometimes tend to be different. For example line A, the tumors for the control group reached it's ethical limit at day 20, and will have to be sacrificed. Means I will only have 20 days of data which I can compare treated vs control.

However, for line B, the tumors for control group remains within limit throughout the whole study, for example 40 days. That would mean I have 40 days worth of data which I can use.

Question:

1. If compare between lines, I can only use data up to 20 days for line B, right?

2. Usually TGI and T/C ratio applies to only one time point, which is usually the end point. My end point for both lines are different, which mean it is not really good to use this method to quantify, unless I do the TGI calculation at the same time point for both lines (eg Day 20), right?

3. Are there other suitable methods I can use to quantify this drug effect on tumors other than TGI and T/C ratio?

Thank you for your time.