In contrast to numerous diseases, psychiatric diseases have not enjoyed the same kind of improvements in scientific disease understanding and in innovative new drug introductions as have other diseases with high unmet medical need. Specifically, progress in this therapeutic category has been slow and discouraging, and indeed, many drug companies have been abandoning this category over the past decade.
Let’s consider the current status of two major psychiatric diseases: schizophrenia and depression. For schizophrenia, there have been 11 new drug approvals for typical or so-called first-generation antipsychotics (1957-1984) and 10 for atypical or so-called second-generation antipsychotics (1989-2010); these are the two pharmacologic classes for schizophrenia (click on drugs for Schizophrenia). For depression, there have been 4 and 7 new drug approvals for each of the two older pharmacologic classes, MAO inhibitors (1951-2006) and tricyclic antidepressants (1959-1979), respectively, while there have been 8 and 4 new drug approvals for each of the two newer pharmacologic classes, SSRI’s or selective serotonin reuptake inhibitors (1987-2013) and SNRI’s or serotonin norepinephrine reuptake inhibitors (1993-2013), respectively (click on drugs for Depression). Of note is that the period of regulatory approvals for these different pharmacologic classes has typically been between approximately 20 and 30 years.
While this listing, based on FDA’s Drugs@FDA database, and not including new formulations of previously approved drugs, may suggest there has been considerable activity in new drug introductions for these two psychiatric diseases, for the most part these have involved old mechanisms, and treatment with these drugs not infrequently requires trial and error approaches and drug combinations. This current status clearly suggests that there is a great need for significant and transformative changes in treatment options for psychiatric diseases. Thus, what matters most isn’t simply the number of new FDA drug approvals per pharmacologic classes or the time period over which they were of regulatory interest, but rather the appropriateness of the mechanisms of action in question to successfully combat the underlying pathogenesis and symptomatology.
Refer to pages 17 and 18 of Progression Of Modern Therapeutics (2013) available under Reports on this website; this Report also includes the methodology used.