AHFS/Drugs.com Monograph Routes ofadministration Topical CAS ID 99011-02-6 | MedlinePlus a698010 Molar mass 240.304 g/mol | |
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Trade names Aldara originally. Many brands available. License data EU EMA: AldaraUS FDA: Imiquimod Pregnancycategory AU: B1US: C (Risk not ruled out) | ||
Imiquimod (INN) is a prescription medication that acts as an immune response modifier and is used to treat genital warts, superficial basal cell carcinoma, and actinic keratosis. Scientists at 3M's pharmaceuticals division discovered the drug and 3M obtained the first FDA approval in 1997 under the brand Aldara. As of 2015 imiquimod is generic and is available worldwide under many brands.
Contents
Uses
Imiquimod is a patient-applied cream prescribed to treat genital warts and, secondary to surgery, for basal cell carcinoma, as well as actinic keratosis.
Side effects
Side effects include local inflammatory reactions, such as blisters, a burning sensation, skin redness, dry skin, itching, skin breakdown, skin crusting or scabbing, skin drainage, skin flaking or scaling, skin ulceration, sores, swelling, as well as systemic reactions, such as fever, "flu-like" symptoms, headache, and tiredness.
People who have had an organ transplant and are taking immune-suppressing drugs should not use imiquimod.
Mechanism of action
It is known that imiquimod signals to the innate arm of the immune system through the toll-like receptor 7 (TLR7), commonly involved in pathogen recognition. Cells activated by imiquimod via TLR-7 secrete cytokines (primarily interferon-α (IFN-α), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α)). There is evidence that imiquimod, when applied to skin, can lead to the activation of Langerhans cells, which subsequently migrate to local lymph nodes to activate the adaptive immune system. Other cell types activated by imiquimod include natural killer cells, macrophages and B-lymphocytes. Overall imiquimod acts on several levels, which appear to synergistically underlie the profound antitumoral activity of the compound.
History
Scientists at 3M's pharmaceutical division discovered imiquimod as part of a program to discover inhibitors of herpes virus replication based on a known adenine derivative. 3M obtained the first FDA approval for it in 1997 as a treatment for external genital and perianal warts under the brand, "Aldara". 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.
As of 2015, imiquimod is generic and is available worldwide under many brands.
Research
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.
Imiquimod has also been tested for treatment of vulvar intraepithelial neoplasia, common warts that have proven difficult to treat, and vaginal intraepithelial neoplasia.