... that we can look forward to several new gene therapy drugs in the coming years? This is illustrated by the pie charts with data on various gene therapy products that are in clinical trials worldwide (Figure 10.10). The largest number of these drugs target cancer, with the second largest group belonging to the therapy of various monogenic diseases. Most are still in the first and second phases of clinical testing, but up to 140 such products are currently entering the third phase, which means they are close to approval.