In 2004, 3M obtained FDA approval to market imiquimod as a treatment for superficial basal cell carcinoma.In 2006, 3M sold its pharmaceutical business in the Americas to Graceway Pharmaceuticals, its European pharmaceutical business to Meda AB, and its pharmaceutical business in other territories to two private equity firms.Graceway declared bankruptcy in 2011, after the expiration of the patents on imiquimod, and its assets, including the rights to imiquimod branding and approvals in the Americas, were purchased by Medicis Pharmaceutical.Imiquimod 5% was approved for medical use in the European Union in September 1998. Imiquimod 3.75% was approved for medical use in the European Union in August 2012.As of 2015, imiquimod is generic and is available worldwide under many brands. Research
One randomized double-blind Phase III clinical study found clearance of genital warts (an FDA-approved indication) improved from 9% with placebo to 24.9% with 3.75% imiquimod cream applied for up to eight weeks.Imiquimod has been tested for treatment of molluscum contagiosum. Two large randomized controlled trials, however, found no evidence of effectiveness of imiquimod in treating children with molluscum contagiosum, and concerning adverse effects were also noted. These disprove earlier anecdotal claims and smaller, less reliable studies.Imiquimod has also been tested for treatment of vulvar intraepithelial neoplasia, vaginal intraepithelial neoplasia, common warts (a 2012 Cochrane review found no randomized controlled trials), plantar warts, warts in people with suppressed immune systems, flat warts on face and neck, and warts under and around fingernails and toenails.
The adrenergic substances released by the sympathetic nervous system can also bind to and influence various immunological cells, further providing a connection between the systems. The HPA axis ultimately results in the release of cortisol, which generally has immunosuppressive effects. However, the effect of stress on the immune system is disputed, and various models have been proposed in an attempt to account for both the supposedly "immunodeficiency" linked diseases and diseases involving hyper activation of the immune system. One model proposed to account for this suggests a push towards an imbalance of cellular immunity(Th1) and humoral immunity(Th2). The proposed imbalance involved hyperactivity of the Th2 system leading to some forms of immune hypersensitivity, while also increasing risk of some illnesses associated with decreased immune system function, such as infection and cancer. Effects of chronic stress
Chronic stress is a term sometimes used to differentiate it from acute stress. Definitions differ, and may be along the lines of continual activation of the stress response, stress that causes an allostatic shift in bodily functions, or just as "prolonged stress". For example, results of one study demonstrated that individuals who reported relationship conflict lasting one month or longer have a greater risk of developing illness and show slower wound healing. Similarly, the effects that acute stressors have on the immune system may be increased when there is perceived stress and/or anxiety due to other events. For example, students who are taking exams show weaker immune responses if they also report stress due to daily hassles.