It depends on the percentage of people who show complete tumor regression with existing approaches, and on the relative costs and side effects. For instance, if only 25 percent of people show complete tumor regression with existing approaches, then getting the number up to 50 percent is a huge deal. Or, if the percentage is in line with existing approaches but the cost is much lower, that's another big win.
Actually it's more than likely that the combination will reduce the chance of success as chemotherapy will wipe out the immune system (generally). Although some groups have shown very preliminary results that the combination may work it has to be given in a specific timeframe (in the order of days) and would work in specific subsets of the population.
