Fig. 3.

Two proposed methods of clinical evaluation of drug combinations.A. Method 1 assumes the ineffectiveness of drug A at the maximum tolerated dose and a therapeutic success after adding the minimum effective dose of drug B (first step), an unsuccessful attempt at discontinuing drug A (second step) and a repeated therapeutic success after reinstating drug A but at the minimum effective dose (third step). B. Method 2 assumes a partial effectiveness of drug A used at a high dose and a therapeutic success after adding a minimal effective dose of drug B (first step) and the maintenance of the said effect after lowering the dose of the first drug without attempting to discontinue its administration (step two)