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ECHA InfoCard | 100.158.124 |
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Formula | C22H26FN3O2 |
Molar mass | 383.467 g·mol−1 |
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Losmapimod (GW856553X) is an investigational drug that reached stage III clinical trials for multiple medical conditions, but did not prove efficacy. It was most recently in development by Fulcrum Therapeutics for the treatment of facioscapulohumeral muscular dystrophy (FSHD). Losmapimod selectively inhibits enzymes p38α/β mitogen-activated protein kinases (MAPKs), which are modulators of DUX4 expression and mediators of inflammation. [1]
Losmapimod was discovered and unsuccessfully developed by GSK for treating multiple medical conditions. Despite failing to prove efficacy, GSK clinical trials showed that losmapimod is generally well tolerated across more than 3,500 subjects. [2] [3] [4]
GSK investigated losmapimod as a therapeutic for patients post-myocardial infarction (heart attack). Despite phase II clinical trials [5] [6] [7] [8] [9] [10] the phase IIIA clinical trial (LATITUDE) [11] failed to show significantly improved clinical outcomes. [12] In October 2015 GSK announced cancelling the planned phase IIIB trial, but would "evaluate all options for future development." [13]
GSK investigated losmapimod as a therapeutic for COPD, but multiple phase II clinical trials [14] [15] [16] failed to show that losmapimod improves exercise tolerance, [3] lung function, [3] arterial inflammation, [4] endothelial function, [4] or rate of COPD exacerbations [17] in subjects with COPD. GSK terminated development of losmapimod for COPD in 2016. [18] [19]
GSK investigated losmapimod as a therapeutic for major depressive disorder (MDD) on the basis of depression being correlated with elevated pro-inflammatory cytokines. [20] Phase II clinical trials [21] [22] failed to show a significant improvement in depression symptoms and biomarkers. [20]
In 2019 Fulcrum therapeutics acquired from GSK the rights to losmapimod. [23] Fulcrum identified p38α/β MAPK inhibitors as potent suppressors of DUX4 expression, the de-suppression of which is accepted as the cause FSHD, and then chose to develop losmapimod for FSHD due to "substantial and attractive preclinical and clinical data" from previous GlaxoSmithKline (GSK) clinical trials. [2] Although a 2021 phase IIb clinical trial showed slowing of muscle deterioration, [24] [25] [26] [27] [28] , a 2024 phase III clinical trial failed to demonstrate efficacy.[ citation needed ]
A mitogen-activated protein kinase is a type of serine/threonine-specific protein kinases involved in directing cellular responses to a diverse array of stimuli, such as mitogens, osmotic stress, heat shock and proinflammatory cytokines. They regulate cell functions including proliferation, gene expression, differentiation, mitosis, cell survival, and apoptosis.
Facioscapulohumeral muscular dystrophy (FSHD) is a type of muscular dystrophy, a group of heritable diseases that cause degeneration of muscle and progressive weakness. Per the name, FSHD tends to sequentially weaken the muscles of the face, those that position the scapula, and those overlying the humerus bone of the upper arm. These areas can be spared, and muscles of other areas usually are affected, especially those of the chest, abdomen, spine, and shin. Almost any skeletal muscle can be affected in advanced disease. Abnormally positioned, termed 'winged', scapulas are common, as is the inability to lift the foot, known as foot drop. The two sides of the body are often affected unequally. Weakness typically manifests at ages 15–30 years. FSHD can also cause hearing loss and blood vessel abnormalities at the back of the eye.
Mitogen Activated Protein (MAP) kinase kinase kinase is a serine/threonine-specific protein kinase which acts upon MAP kinase kinase. Subsequently, MAP kinase kinase activates MAP kinase. Several types of MAPKKK can exist but are mainly characterized by the MAP kinases they activate. MAPKKKs are stimulated by a large range of stimuli, primarily environmental and intracellular stressors. MAPKKK is responsible for various cell functions such as cell proliferation, cell differentiation, and apoptosis. The duration and intensity of signals determine which pathway ensues. Additionally, the use of protein scaffolds helps to place the MAPKKK in close proximity with its substrate to allow for a reaction. Lastly, because MAPKKK is involved in a series of several pathways, it has been used as a therapeutic target for cancer, amyloidosis, and neurodegenerative diseases. In humans, there are at least 19 genes which encode MAP kinase kinase kinases:
p38 mitogen-activated protein kinases are a class of mitogen-activated protein kinases (MAPKs) that are responsive to stress stimuli, such as cytokines, ultraviolet irradiation, heat shock, and osmotic shock, and are involved in cell differentiation, apoptosis and autophagy. Persistent activation of the p38 MAPK pathway in muscle satellite cells due to ageing, impairs muscle regeneration.
Mitogen-activated protein kinase kinase is a dual-specificity kinase enzyme which phosphorylates mitogen-activated protein kinase (MAPK).
Erdosteine is a molecule with mucolytic activity. Structurally it is a thiol derivative characterized by the presence of two thiol groups. These two functional sulfhydryl groups contained in the molecule are released following first-pass metabolism with the conversion of erdosteine into its pharmacologically active metabolite Met-I.
Cilomilast is a drug which was developed for the treatment of respiratory disorders such as asthma and chronic obstructive pulmonary disease (COPD). It is orally active and acts as a selective phosphodiesterase-4 inhibitor.
Riociguat, sold under the brand name Adempas, is a medication by Bayer that is a stimulator of soluble guanylate cyclase (sGC). It is used to treat two forms of pulmonary hypertension (PH): chronic thromboembolic pulmonary hypertension (CTEPH) and pulmonary arterial hypertension (PAH). Riociguat constitutes the first drug of the class of sGC stimulators. The drug has a half-life of 12 hours and will decrease dyspnea associated with pulmonary arterial hypertension.
Phosphoinositide 3-kinase inhibitors are a class of medical drugs that are mainly used to treat advanced cancers. They function by inhibiting one or more of the phosphoinositide 3-kinase (PI3K) enzymes, which are part of the PI3K/AKT/mTOR pathway. This signal pathway regulates cellular functions such as growth and survival. It is strictly regulated in healthy cells, but is always active in many cancer cells, allowing the cancer cells to better survive and multiply. PI3K inhibitors block the PI3K/AKT/mTOR pathway and thus slow down cancer growth. They are examples of a targeted therapy. While PI3K inhibitors are an effective treatment, they can have very severe side effects and are therefore only used if other treatments have failed or are not suitable.
Pirfenidone, sold under the brand name Pirespa among others, is a medication used for the treatment of idiopathic pulmonary fibrosis. It works by reducing lung fibrosis through downregulation of the production of growth factors and procollagens I and II.
Ifetroban is a potent and selective thromboxane receptor antagonist. It has been studied in animal models for the treatment of cancer metastasis, myocardial ischemia, hypertension, stroke, thrombosis, cardiomyopathy, and for its effects on platelets. Clinical trials are evaluating the therapeutic safety and efficacy of oral ifetroban capsules for the treatment of cancer metastasis, cardiovascular disease, aspirin exacerbated respiratory disease, systemic sclerosis, and Duchenne muscular dystrophy.
Givinostat, sold under the brand name Duvyzat is a medication used for the treatment of Duchenne muscular dystrophy. It is a histone deacetylase inhibitor with potential anti-inflammatory, anti-angiogenic, and antineoplastic activities. It is a histone deacetylase (HDAC) inhibitor that works by targeting pathogenic processes to reduce inflammation and loss of muscle.
ELOM-080 is the active ingredient of the herbal medicine named GeloMyrtol forte. The acronym ELOM stands for the oils from Eucalyptus, Lemon, (Sweet) Orange and Myrtle that it contains.
Nintedanib, sold under the brand names Ofev and Vargatef, is an oral medication used for the treatment of idiopathic pulmonary fibrosis and along with other medications for some types of non-small-cell lung cancer.
A MEK inhibitor is a chemical or drug that inhibits the mitogen-activated protein kinase kinase enzymes MEK1 and/or MEK2. They can be used to affect the MAPK/ERK pathway which is often overactive in some cancers.
Ralimetinib (LY2228820) is a small molecule experimental cancer drug in development by Eli Lilly. Although originally thought to be a p38 mitogen-activated protein kinase (MAPK) inhibitor, it has since been reported that it acts instead as an epidermal growth factor receptor (EGFR) inhibitor.
Abrocitinib, sold under the brand name Cibinqo, is a medication used for the treatment of atopic dermatitis (eczema). It is a Janus kinase inhibitor and it was developed by Pfizer. It is taken by mouth.
PH-797804 is a drug which acts as a selective inhibitor of the enzyme p38 mitogen-activated protein kinase. It has antiinflammatory effects and has been researched for the treatment of inflammatory lung conditions such as chronic obstructive pulmonary disease and COVID-19. While it has not been adopted for clinical use, it remains widely used in research.
NJK14047 is a drug which acts as a selective inhibitor of the enzyme p38 mitogen-activated protein kinase. It has antiviral and antiinflammatory effects and was originally developed as a potential treatment for inflammatory lung conditions such as influenza. Subsequent research has also shown promise for various other conditions in which inflammation plays a role, including Alzheimer's disease, asthma, arthritis and psoriasis.
Pamapimod is an investigational drug which is being evaluated for the treatment of autoimmune diseases. It is a p38 mitogen-activated protein kinase inhibitor. It has been evaluated in a phase 2 clinical trial for the treatment of rheumatoid arthritis, but was found not to be effective. It has subsequently been investigated as a possible treatment for osteoarthritis.