Access and Utilization of New Antidepressant and Antipsychotic Medications. A. New Chemical Entities and Generic Competition

01/01/2000

The entry of new chemical entities into the psychotherapeutic market in the coming years will profoundly alter the dynamics shaping access to and utilization of these products in much the same way the launch of the current generation of products changed the market within the last decade. It can be expected that these products will be launched with at least modest price premiums to current agents.

Since the end of the primary research phase of this product, Pharmacia & Upjohn has launched reboxetine (Vestra®) as a new therapy for depression. This drug is the first in what is likely to be a new class of antidepressants that work almost exclusively on the norepinephrine system. Pfizer is expected to re-submit a New Drug Application for a new atypical antipsychotic, ziprasidone (Zeldox®) in 2000, even though this product was received a non-approvable letter from FDA in 1999.

In addition, our research shows over 10 new products for depression in Phase III, with launch dates expected as early at 2002. An additional 17 products are in Phase II, with expected launch dates as early as 2003. For schizophrenia or other psychotic disorders, we are aware of more than seven products in Phase III or already launched in other countries. It may be expected that several of these will attempt launch in the US.

However, even as these new agents are launched, the current group of antidepressants and antipsychotics will be nearing the end of their patent life. Fluoxetine will lose its patent exclusivity in 2003, with many of the other antidepressants following closely behind. The entry of generic competition will drive the prices of these agents down, even as their manufacturers attempt novel methods of extending their brand identity. For example, both Eli Lilly and Forest Labs have obtained use patents for stereochemically-pure isomers of their products, fluoxetine and citalopram. These products are currently in clinical development, and their ability to extend brand life will largely depend on the extent to which they exhibit any improvement in therapeutic profile. Eli Lilly is also testing a combination product containing both fluoxetine and olanzapine to be used in severe and/or atypical depression.