US biopharmaceutical companies currently have 119 novel medicines in development for the treatment of mental and addictive disorders, according to new industry data.

The products in development are all either currently in clinical trials or under review by the US Food and Drug Administration (FDA), says the report, which is published by the Pharmaceutical Research and Manufacturers of America (PhRMA). 

Products currently in R&D include: 36 for schizophrenia, which affects 2.4 million US adults; 29 for depression – 21 million US adults; 20 for substance/addictive disorders, which cost the nation more than $600 million each year; 15 for attention deficit/hyperactivity disorder (ADHD), affecting one in every 20 US children; and 15 for anxiety disorders, affecting 40 million US adults.

Innovative products for these conditions which are now in the pipeline include:

- a triple reuptake inhibitor that targets three chemical pathways in the brain – serotonin, norepinephrine and dopamine – for the once-daily treatment of ADHD;

- a therapeutic vaccine for cocaine addiction;

- treatments for depression including one that targets glutamate, a common neurotransmitter found in the brain and is involved in memory, learning and cognition, and one for major depressive disorder in patients who have not responded to current treatments which combines an opioid modulator with an opioid stimulator;

- a potential treatment for social phobia which has a unique mechanism of action and is part of a new class of psychotropic pherines; and

-  a number of potential treatments for schizophrenia which are inhibitors of phosphodiesterase (PDE); these are highly selective and mimic the effects of current treatments but also activate certain receptors which may decrease the negative side effects of current treatments and increase the positive effect on cognition.

Mental disorders are the leading cause of disability in the US, according to the National Institute of Mental Health (NIMH), which estimates that one in four US adults, or 61.5 million people, have been diagnosed with a mental health disorder. Also, around 13.6 million people in the US, or one in 17, suffer from a serious mental illness, and these are costing the nation more than $317 billion each year in lost wages, health care expenditures and disability benefits, it adds.