Table 3.
Numbers of publications, clinical trials and marketed products of 10 advanced pharmaceutical technologies (1980–2017).
| Key Drug Delivery Technologies | Number of Global Publications | Number of Global Clinical Trials | Ratio of Clinical Trials to Publications (%) | Number of Clinical Trials in US | Number of Marketed Products in the US | Ratio of Products to Clinical Trials in the US (%) |
|---|---|---|---|---|---|---|
| Oral sustained release preparations | 7150 | 1798 | 25.15 | 859 | 205 | 24.55 |
| Transdermal patch | 4161 | 570 | 13.70 | 323 | 54 | 17.09 |
| Aerosol inhalation * | 3204 | 342 | 10.67 | 171 | 16 | 9.36 |
| Powder inhalation * | 5227 | 878 | 16.80 | 383 | 25 | 6.53 |
| Spray inhalation * | 2284 | 194 | 8.49 | 82 | 4 | 4.88 |
| Liposome injection # | 3885 | 342 | 8.80 | 232 | 8 | 3.45 |
| Emulsion injection # | 5033 | 269 | 5.34 | 119 | 5 | 4.20 |
| Microsphere injection # | 1329 | 92 | 6.92 | 45 | 11 | 7.32 |
| Suspension injection # | 3558 | 58 | 1.63 | 40 | 2 | 5.00 |
| Nanoparticle injection # | 5468 | 601 | 10.99 | 276 | 11 | 5.07 |
* belong to inhalation delivery system. # belong to injection delivery system.