"Peak Drug"?

Seeming to be a version of "peak oil," in which discoveries inexorably decline at a greater rate than usage, the entire drug development system appears to be in a secular downward trend. Such a trend seems inconceivable. Our historical experience indicates that we simply need to try harder, spend more money, or "think outside the box." But thinking outside the box here may indicate that we have reached some limit where increased effort will simply yield decreasing results. If so, Big Pharma will continue to consolidate.