INM-405 for the Treatment of Orofacial Pain
According to an Institute of Medicine Report: Relieving Pain in America: A Blueprint for Transforming Prevention, Care, Education and Research, pain is a significant public health problem that is estimated to have an economic cost in the United States of at least $560-$635 billion annually. This includes estimated total incremental costs of pain-related healthcare ranging from $261-$300 billion and $297-$336 billion due to lost productivity.
General Categories of Pain
Nociceptive pain is caused by stimulation of sensory nerve fibers that respond to stimuli approaching or exceeding harmful intensity (nociceptors) and may be classified according to the mode of noxious stimulation. The most common categories are “thermal” (e.g., heat or cold), “mechanical” (e.g., crushing, tearing, shearing, etc.) and “chemical” (e.g., iodine in a cut or chemicals released during inflammation).
Neuropathic pain is caused by damage or disease affecting any part of the nervous system involved in bodily feelings (the somatosensory system). Peripheral neuropathic pain is often described as “burning”, “tingling”, “electrical”, “stabbing”, or “pins and needles”. Bumping the “funny bone” elicits acute peripheral neuropathic pain.
According to a September 2016 fact sheet from the International Association for the Study of Pain, one type of chronic pain that may lend itself well to topical therapy is a subset of neuropathic pain called orofacial pain. In this category, InMed is currently focusing on two particular conditions: temporomandibular disorders (TMD) and trigeminal neuralgia (TN).
Both conditions are rooted in the trigeminal nerve that services the head and eyes (ophthalmic nerve), the cheek/upper lip (maxillary) and the side of the face/mandible joint/jaw (mandibular). Orofacial is common and has many causes. Several orofacial pain types are attributed to mechanical or neural injury near the surface of the skin, and this includes TMD and TN.