阅读说明：本技术 治疗急性或慢性疼痛的方法 (Method for treating acute or chronic pain ) 是由 A.耶基拉拉 D.罗伯森 M.佩恩特 于 2018-10-08 设计创作，主要内容包括：本发明提供了治疗慢性和急性疼痛的方法。例如,本发明提供了治疗神经性和炎性疼痛的方法。(The present invention provides methods for treating chronic and acute pain. For example, the invention provides methods of treating neuropathic and inflammatory pain.)

1. A method for treating chronic pain in an animal comprising administering to the animal an amount of Compound A(A) Or a pharmaceutically acceptable salt thereof.

2. The method of claim 1, wherein the chronic pain is neuropathic pain.

3. The method of claim 2, wherein the neuropathic pain is diabetic neuropathy-induced pain, chemotherapy-induced pain, sciatica pain, carpal tunnel syndrome pain, trigeminal neuralgia pain, fibromyalgia pain, or post-herpetic neuralgia pain.

4. The method of claim 1, wherein the chronic pain is inflammatory pain.

5. The method of claim 4, wherein the inflammatory pain is somatic pain, rheumatoid arthritis pain, osteoarthritis pain, autoimmune disease-related pain, cancer pain, post-operative pain, or post-injury pain.

6. A method for treating acute pain in an animal comprising administering to the animal an amount of Compound A(A) Or a pharmaceutically acceptable salt thereof.

7. The method of claim 6, wherein the acute pain is neuropathic pain.

8. The method of claim 7, wherein the neuropathic pain is diabetic neuropathy-induced pain, chemotherapy-induced pain, sciatica pain, carpal tunnel syndrome pain, trigeminal neuralgia pain, fibromyalgia pain, or post-herpetic neuralgia pain.

9. The method of claim 6, wherein the acute pain is inflammatory pain.

10. The method of claim 9, wherein the inflammatory pain is somatic pain, rheumatoid arthritis pain, osteoarthritis pain, autoimmune disease-related pain, cancer pain, post-operative pain, or post-injury pain.

11. The method of any one of claims 1-10, wherein the animal is a human.

12. Having a compound A

13. Having a compound A

14. The compound of claim 12 or 13, wherein the chronic pain is neuropathic pain.

15. The compound of claim 14, wherein the neuropathic pain is diabetic neuropathy-induced pain, chemotherapy-induced pain, sciatica pain, carpal tunnel syndrome pain, trigeminal neuralgia pain, fibromyalgia pain, or post-herpetic neuralgia pain.

16. The compound of claim 12 or 13, wherein the chronic pain is inflammatory pain.

17. The compound of claim 16, wherein the inflammatory pain is somatic pain, rheumatoid arthritis pain, osteoarthritis pain, pain associated with autoimmune disease, cancer pain, post-operative pain, or post-injury pain.

18. Having a compound A

19. Having a compound A(A) A compound of the structure of (a), or a pharmaceutically acceptable salt thereof, for use in the manufacture of a medicament for treating acute pain in an animal.

20. The compound of claim 18 or 19, wherein the acute pain is neuropathic pain.

21. The compound of claim 20, wherein the neuropathic pain is diabetic neuropathy-induced pain, chemotherapy-induced pain, sciatica pain, carpal tunnel syndrome pain, trigeminal neuralgia pain, fibromyalgia pain, or post-herpetic neuralgia pain.

22. The compound of claim 18 or 19, wherein the acute pain is inflammatory pain.

23. The compound of claim 22, wherein the inflammatory pain is somatic pain, rheumatoid arthritis pain, osteoarthritis pain, pain associated with autoimmune disease, cancer pain, post-operative pain, or post-injury pain.

24. The method or compound of any one of claims 1 to 24, wherein about 100 meg of compound a, or pharmaceutically acceptable salt thereof, is administered once daily or is suitable for administration once daily.

25. The method or compound of any one of claims 1 to 24, wherein about 100 meg of compound a, or pharmaceutically acceptable salt thereof, is administered two, three, four, or five times per day or is suitable for administration two, three, four, or five times per day.

26. The method or compound of any one of claims 1 to 24, wherein about 1mg of compound a or a pharmaceutically acceptable salt thereof is administered once daily or is suitable for once daily administration.

27. The method or compound of any one of claims 1 to 24, wherein about 1mg of compound a or a pharmaceutically acceptable salt thereof is administered two, three, four or five times daily or is adapted for administration two, three, four or five times daily.

28. The method or compound of any one of claims 1 to 24, wherein about 10mg of compound a or a pharmaceutically acceptable salt thereof is administered once daily or is suitable for once daily administration.

29. The method or compound of any one of claims 1 to 24, wherein about 10mg of compound a or a pharmaceutically acceptable salt thereof is administered twice, three times, four times, or five times daily or is adapted to be administered twice, three times, four times, or five times daily.

30. The method or compound of any one of claims 1 to 24, wherein about 20mg of compound a or a pharmaceutically acceptable salt thereof is administered once daily or is suitable for once daily administration.

31. The method or compound of any one of claims 1 to 24, wherein about 20mg of compound a or a pharmaceutically acceptable salt thereof is administered two, three, four or five times daily or is adapted to be administered two, three, four or five times daily.

32. The method or compound of any one of claims 1 to 24, wherein about 100mg of compound a or a pharmaceutically acceptable salt thereof is administered once daily or is suitable for once daily administration.

33. The method or compound of any one of claims 1 to 24, wherein about 100mg of compound a or a pharmaceutically acceptable salt thereof is administered twice, three times, four times, or five times daily or is adapted for administration twice, three times, four times, or five times daily.

34. The method or compound of any one of claims 1 to 24, wherein about 100 μ g/kg of compound a or a pharmaceutically acceptable salt thereof is administered once per day or is adapted for once per day administration.

35. The method or compound of any one of claims 1 to 24, wherein about 100 μ g/kg of compound a or a pharmaceutically acceptable salt thereof is administered two, three, four or five times daily or is adapted for administration two, three, four or five times daily.

36. The method or compound of any one of claims 1 to 24, wherein about 300 μ g/kg of compound a or a pharmaceutically acceptable salt thereof is administered once per day or is adapted for once per day administration.

37. The method or compound of any one of claims 1 to 24, wherein about 300 μ g/kg of compound a or a pharmaceutically acceptable salt thereof is administered two, three, four or five times daily or is adapted for administration two, three, four or five times daily.

Brief description of the drawings

FIG. 1 is a graph showing that a decrease in thermal withdrawal threshold in rats four hours after an intraplantar incision (postoperative baseline) was reversed by intravenous injection of Compound A (300. mu.g/kg), but not by intravenous injection of saline (control) or ibuprofen (30 mg/kg). Circles, squares and triangles represent the average withdrawal latency values when compound a, saline or ibuprofen were administered, respectively. Error bars represent standard error of the mean.

Figure 2 is a graph showing that intravenous injection of compound a (100 μ g/kg) reversed the change in mechanical withdrawal threshold in rats after an intraplantar incision (surgery), but saline (control) failed to reverse. Circles and squares represent the average withdrawal latency values when compound a or saline, respectively, were administered. Error bars represent standard error of the mean.

Figure 3 is a graph showing that the reduced mechanical withdrawal threshold following spinal nerve ligation (post-SNL) in rats was reversed by oral administration of compound a or gabapentin, but not by oral vehicle (saline) administration. Circles, squares and triangles represent mean withdrawal latency values when compound a, saline or gabapentin were administered, respectively. Error bars represent standard error of the mean.

Detailed Description

Physically bound receptor complexes, collectively known AS homomers (complexes of similar receptors) or heteromers (complexes of different receptors) depending on their composition, represent a new class of targets that may have new and unique physiological effects when compared to the individual receptors forming the complex (yekkira AS, kaluyzzny AE, Portoghese PS.ACS Chemical Neuroscience2010, 1(2):146-154, doi:10.1021/cn9000236; Yekkirala AS.Life Sci.2013, 92: 438-Nat. Rev. Drug Discov.16,545-564) N-naphthoyl- β -naltrexamine (NNTA, Compound A) is an pioneer new drug activator or agonist of the new target mu-kappa opioid receptor heteromer with picomolar binding affinity and functional potency for those receptors (Yekkira AS, Lunzer MM, McCurdy CR et alProc. Natl. Acad. Sci. USA2011, 108(12):5098-5103, doi:10.1073/pnas.1016277108; Portoghese, PS and Yekkirala, AS. U.S. Pat. No. 8,609,682, "US' 682"). US' 682 discloses that compound a is useful as an analgesic against nociceptive pain, with reduced dependence, tolerance and constipation relative to morphine. As discussed in more detail below, nociceptive pain differs from other types of pain, such as inflammatory pain, pain caused by chemotherapy, pain experienced after surgery, and neuropathic pain. Currently, there is no evidence that ligands targeting mu-kappa opioid receptor heteromers may have any effect on chronic pain, such as neuropathic pain, pain experienced post-operatively, inflammatory pain, or pain induced by chemotherapy. Furthermore, as a class of compounds, opioids (e.g., morphine) are not effective in treating a particular pain syndrome, such as neuropathic pain or chemotherapy-induced pain. The above shows that neither mechanistic targets nor all classes of compounds show the use of compound a in these conditions of the invention in chronic pain conditionsAnd (5) effect. The present application discloses for the first time that compound a is effective in the treatment of various types of chronic and acute pain, including neuropathic pain, post-operative experienced pain, inflammatory pain, or chemotherapy-induced pain, which are not amenable to treatment with other known analgesics.

Nociceptive pain

Nociceptive pain is activated in response to an underlying tissue injury, or stimulus with the potential to cause injury. Here, the stimulus acts directly on the peripheral nociceptors to initiate pain transmission. After noxious stimuli activate nociceptors, this information can be conveyed through the nervous system by thin myelin, relatively fast a-fibers, or also by unmyelinated, relatively slow, unmyelinated C-fibers. This sensory information is transmitted through primary afferent neurons, then secondary neurons (such as in the spinal cord) before the information is transmitted to the brain where pain is ultimately perceived. Clinically, acute nociceptive pain has an underlying cause, persists for less than 6 months, and resolves after removal or repair of the underlying injury or stimulus. Examples where nociceptive pain may be present include, but are not limited to, common sports injuries such as sprains and strains, post-operative pain (pain resulting from surgery), pain resulting from tissue trauma, burn pain, and ischemic or vascular pain. In scientific studies nociceptive pain is represented by various animal models, including the tail-flick model used in rats. Nociceptive pain is distinct from inflammatory pain, but is often accompanied by inflammatory pain, which can occur when the immune system is activated in response to tissue injury, or noxious stimuli.

Inflammatory pain

One of the main categories of pain disorders belongs to the category of inflammatory pain or pain caused by inflammation in the body. Indeed, one of the main features of inflammation in the body is pain (known as allodynia) induced by a stimulus that is usually harmless. In addition, noxious stimuli may also exhibit an enhanced pain response (known as hypersensitivity). Typical examples of inflammatory pain in humans are rheumatoid arthritis, osteoarthritis, post-injury inflammatory pain and pancreatic inflammatory pain or pancreatitis pain.

From a mechanistic point of view, inflammation of tissue injury is associated with the release of several immune mediators, bradykinin, histamine, 5-hydroxytryptamine (5-HT), ATP, and nitric oxide, to name a few. Their activated pathways lead to the recruitment of immune cells that release additional cytokines, chemokines and other endogenous ligands that produce pain (cause pain), resulting in the perception of pain (Kidd BL and Urban LA. Br. J. Anesthesiology 2001; 87: 3-11). The persistence and secretion of these ligands results in hypersensitivity of sensory neurons near the site of initial injury, which is also referred to as peripheral sensitization. Prolonged peripheral sensitization can lead to sensitization or "central" sensitization of the entire central nociceptive pathway (Woolf CJ. Nature 1983; 306: 686-8). It is the combination of these mechanisms that causes chronic pain in animals.

With the insight of such mechanisms, it is important to consider that the inflammatory pain syndrome is refractory to several commonly used analgesics (e.g., opioids) (Sullivan MD, Edlund MJ, Fan M-Y et alPain2008, 138:440–449; Jones JL, Loftus EV.Am J Gastroenterol. 2005, 100:2230–2232; BallantyneJC, Mao J.N Engl J Med. 2003, 349:1943–1953; Chou R, Ballantyne JC,Fanciullo GJ, et al.J Pain2009, 10:147–159; Ballantyne JC.Pain Physician2007, 10:479-491). In addition, NSAIDs, while effective in immediate relief of pain, have severe GI and cardiac side effects that limit their long-term use (Kidd BL and Urban LA. Br. J. Anesthesiology 2001; 87: 3-11). It should also be noted that the effect of gabapentin (or Neurontin) for the treatment of neuropathic pain on inflammatory pain is also ambiguous (Werner MU, Perkins FM, Holte K, Pedersen JL, Kehlet H.Reg Anesth Pain Med2001, 26(4) 322-8). All this clearly indicates the specificity of this particular set of chronic pain syndromes.

Neuropathic pain

In contrast to nociceptive and inflammatory pain, neuropathic pain is a pathological state of pain that is triggered by changes in the somatosensory nervous system. Neuropathic pain is not a protective response, but rather is a protective responseIn which pain can occur spontaneously and in response to normal, innocuous stimuli. Neuropathic pain can manifest itself as stinging or burning sensations in a patient, often classified according to the location of the pain, and can wax and subside during the day or lifetime. Biologically, neuropathic pain is a manifestation of neurological dysfunction. These changes may include action potentials, synaptic transmission, and changes in neural circuits [ Costigan M, Scholz J, Woolf CJ.Annual review of neuroscience2009, 32:1-32, doi:10.1146/annurev.neuro.051508.135531]. Neuropathic pain can be caused by alcoholism, amputation, chemotherapy, diabetes, HIV infection, multiple myeloma, multiple sclerosis, nervous system injury, herpes zoster, syphilis, thyroid problems, post herpetic neuralgia, back pain, cancer neuropathy, phantom limb pain, and carpal tunnel syndrome. Neuropathic pain may include persistent spontaneous pain as well as allodynia. Neuropathic pain is also characterized by hyperalgesia, in which there is an enhanced response to a pain stimulus that is usually negligible, such as a needle stick. Neuropathic pain is notoriously difficult to treat and is generally refractory to all available drugs (Dubner R.Pain1991, 47:1-2; Fields HL.Pain1988, 35:365-7; ArnerS, Meyerson BA.Pain1988, 33:11-23; Dellemijn P.Pain1999, 80: 453-62;McQuay HJ.Acta Anaesthesiol Scand1997, 41:175-83; Wall PD.Pain1990, 43:267-8; Portenoy RK, Foley KM, Inturrisi CE.Pain1990, 43:273-86). In addition, current treatments have serious side effects including, for example, cognitive changes, sedation, nausea, and addiction in the case of narcotic drugs. Many patients suffering from neuropathic pain are elderly or other medical conditions that have particular limitations on their tolerance to side effects associated with available drug therapy. The inadequacies of current treatments to relieve neuropathic pain without the frequent occurrence of intolerable side effects are manifested in the depression and suicidal tendencies of chronic pain patients. Common animal models of neuropathic pain include, but are not limited to, formalin test, selective nerve injury, chronic crush injury, and sciatic nerve ligation.

The main symptoms of neuropathic pain areAllodynia (Geber C, Baumg ä rtner U, Schwab R, M ü ller H, Stoeter P, Dieterich M, Sommer C, Birklein F, Treede RD.Am J Med.2009 Oct, 122(10 Suppl):S3-12. doi: 10.1016/j.amjmed.2009.04.005; Treede RD,Jensen TS, Campbell JN, Cruccu G, Dostrovsky JO, Griffin JW, Hansson P,Hughes R, Nurmikko T, Serra J.Neurology2008 Apr 29, 70(18):1630-5), which is a pain or pain-like response caused by mechanical, thermal (heat or cold) or other sensory stimuli that are not normally painful. Mechanical stimuli that produce allodynia can be broadly classified as dynamic or static. Static mechanical allodynia occurs when pain is evoked by a static (non-motor) mechanical stimulus that normally does not produce pain, while dynamic allodynia is described as responding to pain that is tapped slightly in a generally pain-free manner. Animal models have been developed that produce symptoms of allodynia, including static mechanical allodynia, dynamic mechanical allodynia, or thermal allodynia, through laboratory-induced disease models, chemical injury, or nerve trauma in animals (such as rodents). Importantly, morphine was only able to block static allodynia, but not dynamic allodynia in the rat neuropathic pain model. In contrast, pregabalin, now considered the standard of care for many types of neuropathic pain, is able to block both types of allodynia (Field MJ, Bramwell S, Hughes J, Singh L.Pain.1999, 83(2): 303-311). Such studies demonstrate a mechanistic difference between neuropathic pain and other types of pain that are better treated by standard μ -opioids.

Methods, compounds and uses for treating pain

Provided herein are methods of treating chronic pain in an animal comprising administering to the animal an amount of compound a

(A) Or a pharmaceutically acceptable salt thereof. In some embodiments, the chronic pain is neuropathic pain. In some embodiments, the neuropathic pain is pain resulting from diabetic neuropathy. In some embodimentsAmong them, neuropathic pain is pain caused by chemotherapy. In some embodiments, the neuropathic pain is sciatica pain. In some embodiments, the neuropathic pain is carpal tunnel syndrome pain. In some embodiments, the neuropathic pain is trigeminal neuralgia pain. In some embodiments, the neuropathic pain is fibromyalgia pain. In some embodiments, the neuropathic pain is post-herpetic neuralgia pain.

In some embodiments, the chronic pain is inflammatory pain. In some embodiments, the inflammatory pain is somatic pain. In some embodiments, the inflammatory pain is rheumatoid arthritis pain. In some embodiments, the inflammatory pain is pain associated with rheumatoid arthritis. In some embodiments, the inflammatory pain is osteoarthritis pain. In some embodiments, the inflammatory pain is pain associated with an autoimmune disease. In some embodiments, the inflammatory pain is pain associated with an autoimmune disease. In some embodiments, the inflammatory pain is cancer pain. In some embodiments, the inflammatory pain is pain associated with cancer. In some embodiments, the inflammatory pain is post-operative pain. In some embodiments, the inflammatory pain is post-injury pain. In some embodiments, the animal with chronic pain treated is a human.

Also provided herein are methods of treating acute pain in an animal comprising administering to the animal an amount of compound a

(A) Or a pharmaceutically acceptable salt thereof. In some embodiments, the acute pain is neuropathic pain. In some embodiments, the neuropathic pain is pain resulting from diabetic neuropathy. In some embodiments, the neuropathic pain is chemotherapy-induced pain. In some embodiments, the neuropathic pain is sciatica pain. In some embodiments, the neuropathic pain is carpal tunnel syndrome pain. In some embodiments, the neuropathic pain is trigeminal neuralgia pain. In some embodiments, the neuropathic pain is fibromyalgia pain. In some embodimentsAmong the neuropathic pain is post-herpetic neuralgia pain.

In some embodiments, the acute pain is inflammatory pain. In some embodiments, the inflammatory pain is somatic pain. In some embodiments, the inflammatory pain is rheumatoid arthritis pain. In some embodiments, the inflammatory pain is pain associated with rheumatoid arthritis. In some embodiments, the inflammatory pain is osteoarthritis pain. In some embodiments, the inflammatory pain is pain associated with an autoimmune disease. In some embodiments, the inflammatory pain is pain associated with an autoimmune disease. In some embodiments, the inflammatory pain is cancer pain. In some embodiments, the inflammatory pain is pain associated with cancer. In some embodiments, the inflammatory pain is post-operative pain. In some embodiments, the inflammatory pain is post-injury pain. In some embodiments, the animal treated for acute pain is a human.

The present application also provides compound a, or a pharmaceutically acceptable salt thereof, for use in treating chronic pain in an animal. In some embodiments, the chronic pain is neuropathic pain. In some embodiments, the neuropathic pain is pain resulting from diabetic neuropathy. In some embodiments, the neuropathic pain is chemotherapy-induced pain. In some embodiments, the neuropathic pain is sciatica pain. In some embodiments, the neuropathic pain is carpal tunnel syndrome pain. In some embodiments, the neuropathic pain is trigeminal neuralgia pain. In some embodiments, the neuropathic pain is fibromyalgia pain. In some embodiments, the neuropathic pain is post-herpetic neuralgia pain. In some embodiments, the chronic pain is inflammatory pain. In some embodiments, the inflammatory pain is somatic pain. In some embodiments, the inflammatory pain is rheumatoid arthritis pain. In some embodiments, the inflammatory pain is pain associated with rheumatoid arthritis. In some embodiments, the inflammatory pain is osteoarthritis pain. In some embodiments, the inflammatory pain is pain associated with an autoimmune disease. In some embodiments, the inflammatory pain is pain associated with an autoimmune disease. In some embodiments, the inflammatory pain is cancer pain. In some embodiments, the inflammatory pain is pain associated with cancer. In some embodiments, the inflammatory pain is post-operative pain. In some embodiments, the inflammatory pain is post-injury pain. In some embodiments, the animal with chronic pain treated is a human.

The present application also provides compound a, or a pharmaceutically acceptable salt thereof, for use in treating acute pain in an animal. In some embodiments, the acute pain is neuropathic pain. In some embodiments, the neuropathic pain is pain resulting from diabetic neuropathy. In some embodiments, the neuropathic pain is chemotherapy-induced pain. In some embodiments, the neuropathic pain is sciatica pain. In some embodiments, the neuropathic pain is carpal tunnel syndrome pain. In some embodiments, the neuropathic pain is trigeminal neuralgia pain. In some embodiments, the neuropathic pain is fibromyalgia pain. In some embodiments, the neuropathic pain is post-herpetic neuralgia pain. In some embodiments, the acute pain is inflammatory pain. In some embodiments, the inflammatory pain is somatic pain. In some embodiments, the inflammatory pain is rheumatoid arthritis pain. In some embodiments, the inflammatory pain is pain associated with rheumatoid arthritis. In some embodiments, the inflammatory pain is osteoarthritis pain. In some embodiments, the inflammatory pain is pain associated with an autoimmune disease. In some embodiments, the inflammatory pain is pain associated with an autoimmune disease. In some embodiments, the inflammatory pain is cancer pain. In some embodiments, the inflammatory pain is pain associated with cancer. In some embodiments, the inflammatory pain is post-operative pain. In some embodiments, the inflammatory pain is post-injury pain. In some embodiments, the animal treated for acute pain is a human.

The present application also provides compound a, or a pharmaceutically acceptable salt thereof, for use in the manufacture of a medicament for treating chronic pain in an animal. In some embodiments, the chronic pain is neuropathic pain. In some embodiments, the neuropathic pain is pain resulting from diabetic neuropathy. In some embodiments, the neuropathic pain is chemotherapy-induced pain. In some embodiments, the neuropathic pain is sciatica pain. In some embodiments, the neuropathic pain is carpal tunnel syndrome pain. In some embodiments, the neuropathic pain is trigeminal neuralgia pain. In some embodiments, the neuropathic pain is fibromyalgia pain. In some embodiments, the neuropathic pain is post-herpetic neuralgia pain. In some embodiments, the chronic pain is inflammatory pain. In some embodiments, the inflammatory pain is somatic pain. In some embodiments, the inflammatory pain is rheumatoid arthritis pain. In some embodiments, the inflammatory pain is pain associated with rheumatoid arthritis. In some embodiments, the inflammatory pain is osteoarthritis pain. In some embodiments, the inflammatory pain is pain associated with an autoimmune disease. In some embodiments, the inflammatory pain is pain associated with an autoimmune disease. In some embodiments, the inflammatory pain is cancer pain. In some embodiments, the inflammatory pain is pain associated with cancer. In some embodiments, the inflammatory pain is post-operative pain. In some embodiments, the inflammatory pain is post-injury pain. In some embodiments, the animal with chronic pain treated is a human.

The present application also provides compound a, or a pharmaceutically acceptable salt thereof, for use in the manufacture of a medicament for treating acute pain in an animal. In some embodiments, the acute pain is neuropathic pain. In some embodiments, the neuropathic pain is pain resulting from diabetic neuropathy. In some embodiments, the neuropathic pain is chemotherapy-induced pain. In some embodiments, the neuropathic pain is sciatica pain. In some embodiments, the neuropathic pain is carpal tunnel syndrome pain. In some embodiments, the neuropathic pain is trigeminal neuralgia pain. In some embodiments, the neuropathic pain is fibromyalgia pain. In some embodiments, the neuropathic pain is post-herpetic neuralgia pain. In some embodiments, the acute pain is inflammatory pain. In some embodiments, the inflammatory pain is somatic pain. In some embodiments, the inflammatory pain is rheumatoid arthritis pain. In some embodiments, the inflammatory pain is pain associated with rheumatoid arthritis. In some embodiments, the inflammatory pain is osteoarthritis pain. In some embodiments, the inflammatory pain is pain associated with an autoimmune disease. In some embodiments, the inflammatory pain is pain associated with an autoimmune disease. In some embodiments, the inflammatory pain is cancer pain. In some embodiments, the inflammatory pain is pain associated with cancer. In some embodiments, the inflammatory pain is post-operative pain. In some embodiments, the inflammatory pain is post-injury pain. In some embodiments, the animal treated for acute pain is a human.

In some embodiments of the methods and compounds of the present disclosure, about 100mcg of compound a or a pharmaceutically acceptable salt thereof is administered once daily or is suitable for administration once daily. In some embodiments, about 100mcg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or is suitable for administration twice daily. In some embodiments, about 100mcg of compound a or a pharmaceutically acceptable salt thereof is administered three times per day or is suitable for administration three times per day. In some embodiments, about 100mcg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times per day. In some embodiments, about 100mcg of compound a or a pharmaceutically acceptable salt thereof is administered five times per day or is adapted to be administered five times per day.

In some embodiments of the methods and compounds of the present disclosure, about 1mg of compound a or a pharmaceutically acceptable salt thereof is administered once daily or is suitable for administration once daily. In some embodiments, about 1mg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or is suitable for administration twice daily. In some embodiments, about 1mg of compound a or a pharmaceutically acceptable salt thereof is administered three times daily or is suitable for administration three times daily. In some embodiments, about 1mg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times daily. In some embodiments, about 1mg of compound a or a pharmaceutically acceptable salt thereof is administered five times daily or is adapted to be administered five times daily.

In some embodiments of the methods and compounds of the present disclosure, about 2 mg of compound a or a pharmaceutically acceptable salt thereof is administered once daily or is suitable for administration once daily. In some embodiments, about 2 mg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or is suitable for administration twice daily. In some embodiments, about 2 mg of compound a or a pharmaceutically acceptable salt thereof is administered three times daily or is suitable for administration three times daily. In some embodiments, about 2 mg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times daily. In some embodiments, about 2 mg of compound a or a pharmaceutically acceptable salt thereof is administered five times daily or is adapted to be administered five times daily.

In some embodiments of the methods and compounds of the present disclosure, about 3 mg of compound a or a pharmaceutically acceptable salt thereof is administered once daily or is suitable for administration once daily. In some embodiments, about 3 mg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or is suitable for administration twice daily. In some embodiments, about 3 mg of compound a or a pharmaceutically acceptable salt thereof is administered three times daily or is suitable for administration three times daily. In some embodiments, about 3 mg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times daily. In some embodiments, about 3 mg of compound a or a pharmaceutically acceptable salt thereof is administered five times daily or is adapted to be administered five times daily.

In some embodiments of the methods and compounds of the present disclosure, about 4 mg of compound a or a pharmaceutically acceptable salt thereof is administered once daily or is suitable for administration once daily. In some embodiments, about 4 mg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or is suitable for administration twice daily. In some embodiments, about 4 mg of compound a or a pharmaceutically acceptable salt thereof is administered three times daily or is suitable for administration three times daily. In some embodiments, about 4 mg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times per day. In some embodiments, about 4 mg of compound a or a pharmaceutically acceptable salt thereof is administered five times daily or is adapted to be administered five times daily.

In some embodiments of the methods and compounds of the present disclosure, about 5mg of compound a or a pharmaceutically acceptable salt thereof is administered once daily or is suitable for administration once daily. In some embodiments, about 5mg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or is suitable for administration twice daily. In some embodiments, about 5mg of compound a or a pharmaceutically acceptable salt thereof is administered three times daily or is suitable for administration three times daily. In some embodiments, about 5mg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times daily. In some embodiments, about 5mg of compound a or a pharmaceutically acceptable salt thereof is administered five times daily or is adapted to be administered five times daily.

In some embodiments of the methods and compounds of the present disclosure, about 6 mg of compound a or a pharmaceutically acceptable salt thereof is administered once daily or is suitable for administration once daily. In some embodiments, about 6 mg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or is suitable for administration twice daily. In some embodiments, about 6 mg of compound a or a pharmaceutically acceptable salt thereof is administered three times daily or is suitable for administration three times daily. In some embodiments, about 6 mg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times daily. In some embodiments, about 6 mg of compound a or a pharmaceutically acceptable salt thereof is administered five times daily or is adapted to be administered five times daily.

In some embodiments of the methods and compounds of the present disclosure, about 7 mg of compound a or a pharmaceutically acceptable salt thereof is administered once daily or is suitable for administration once daily. In some embodiments, about 7 mg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or is suitable for administration twice daily. In some embodiments, about 7 mg of compound a or a pharmaceutically acceptable salt thereof is administered three times daily or is suitable for administration three times daily. In some embodiments, about 7 mg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times daily. In some embodiments, about 7 mg of compound a or a pharmaceutically acceptable salt thereof is administered five times daily or is adapted to be administered five times daily.

In some embodiments of the methods and compounds of the present disclosure, about 8 mg of compound a or a pharmaceutically acceptable salt thereof is administered once daily or is suitable for administration once daily. In some embodiments, about 8 mg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or is suitable for administration twice daily. In some embodiments, about 8 mg of compound a or a pharmaceutically acceptable salt thereof is administered three times daily or is suitable for administration three times daily. In some embodiments, about 8 mg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times daily. In some embodiments, about 8 mg of compound a or a pharmaceutically acceptable salt thereof is administered five times daily or is adapted to be administered five times daily.

In some embodiments of the methods and compounds of the present disclosure, about 9 mg of compound a or a pharmaceutically acceptable salt thereof is administered once daily or is suitable for administration once daily. In some embodiments, about 9 mg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or is suitable for administration twice daily. In some embodiments, about 9 mg of compound a or a pharmaceutically acceptable salt thereof is administered three times daily or is suitable for administration three times daily. In some embodiments, about 9 mg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times daily. In some embodiments, about 9 mg of compound a or a pharmaceutically acceptable salt thereof is administered five times daily or is adapted to be administered five times daily.

In some embodiments of the methods and compounds of the present disclosure, about 10mg of compound a or a pharmaceutically acceptable salt thereof is administered once daily or is suitable for administration once daily. In some embodiments, about 10mg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or is suitable for administration twice daily. In some embodiments, about 10mg of compound a or a pharmaceutically acceptable salt thereof is administered three times daily or is suitable for administration three times daily. In some embodiments, about 10mg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times daily. In some embodiments, about 10mg of compound a or a pharmaceutically acceptable salt thereof is administered five times daily or is adapted to be administered five times daily.

In some embodiments of the methods and compounds of the present disclosure, about 15 mg of compound a or a pharmaceutically acceptable salt thereof is administered once daily or is suitable for administration once daily. In some embodiments, about 15 mg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or is suitable for administration twice daily. In some embodiments, about 15 mg of compound a or a pharmaceutically acceptable salt thereof is administered three times daily or is suitable for administration three times daily. In some embodiments, about 15 mg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times daily. In some embodiments, about 15 mg of compound a or a pharmaceutically acceptable salt thereof is administered five times daily or is adapted to be administered five times daily.

In some embodiments of the methods and compounds of the present disclosure, about 20mg of compound a or a pharmaceutically acceptable salt thereof is administered once daily or is suitable for administration once daily. In some embodiments, about 20mg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or is suitable for administration twice daily. In some embodiments, about 20mg of compound a or a pharmaceutically acceptable salt thereof is administered three times daily or is suitable for administration three times daily. In some embodiments, about 20mg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times daily. In some embodiments, about 20mg of compound a or a pharmaceutically acceptable salt thereof is administered five times daily or is adapted to be administered five times daily.

In some embodiments of the methods and compounds of the present disclosure, about 25 mg of compound a or a pharmaceutically acceptable salt thereof is administered once daily or is suitable for administration once daily. In some embodiments, about 25 mg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or is suitable for administration twice daily. In some embodiments, about 25 mg of compound a or a pharmaceutically acceptable salt thereof is administered three times daily or is suitable for administration three times daily. In some embodiments, about 25 mg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times daily. In some embodiments, about 25 mg of compound a or a pharmaceutically acceptable salt thereof is administered five times daily or is adapted to be administered five times daily.

In some embodiments of the methods and compounds of the present disclosure, about 30mg of compound a or a pharmaceutically acceptable salt thereof is administered once daily or is suitable for administration once daily. In some embodiments, about 30mg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or is suitable for administration twice daily. In some embodiments, about 30mg of compound a or a pharmaceutically acceptable salt thereof is administered three times daily or is suitable for administration three times daily. In some embodiments, about 30mg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times daily. In some embodiments, about 30mg of compound a or a pharmaceutically acceptable salt thereof is administered five times daily or is adapted to be administered five times daily.

In some embodiments of the methods and compounds of the present disclosure, about 35 mg of compound a or a pharmaceutically acceptable salt thereof is administered once daily or is suitable for administration once daily. In some embodiments, about 35 mg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or is suitable for administration twice daily. In some embodiments, about 35 mg of compound a or a pharmaceutically acceptable salt thereof is administered three times daily or is suitable for administration three times daily. In some embodiments, about 35 mg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times daily. In some embodiments, about 35 mg of compound a or a pharmaceutically acceptable salt thereof is administered five times daily or is adapted to be administered five times daily.

In some embodiments of the methods and compounds of the present disclosure, about 40 mg of compound a or a pharmaceutically acceptable salt thereof is administered once daily or is suitable for administration once daily. In some embodiments, about 40 mg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or is suitable for administration twice daily. In some embodiments, about 40 mg of compound a or a pharmaceutically acceptable salt thereof is administered three times daily or is suitable for administration three times daily. In some embodiments, about 40 mg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times daily. In some embodiments, about 40 mg of compound a or a pharmaceutically acceptable salt thereof is administered five times daily or is adapted to be administered five times daily.

In some embodiments of the methods and compounds of the present disclosure, about 45 mg of compound a or a pharmaceutically acceptable salt thereof is administered once daily or is suitable for administration once daily. In some embodiments, about 45 mg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or is suitable for administration twice daily. In some embodiments, about 45 mg of compound a or a pharmaceutically acceptable salt thereof is administered three times daily or is adapted to be administered three times daily. In some embodiments, about 45 mg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times daily. In some embodiments, about 45 mg of compound a or a pharmaceutically acceptable salt thereof is administered five times daily or is adapted to be administered five times daily.

In some embodiments of the methods and compounds of the present disclosure, about 50mg of compound a or a pharmaceutically acceptable salt thereof is administered once daily or is suitable for administration once daily. In some embodiments, about 50mg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or is suitable for administration twice daily. In some embodiments, about 50mg of compound a or a pharmaceutically acceptable salt thereof is administered three times daily or is suitable for administration three times daily. In some embodiments, about 50mg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times daily. In some embodiments, about 50mg of compound a or a pharmaceutically acceptable salt thereof is administered five times daily or is adapted to be administered five times daily.

In some embodiments of the methods and compounds of the present disclosure, about 75 mg of compound a or a pharmaceutically acceptable salt thereof is administered once daily or is suitable for administration once daily. In some embodiments, about 75 mg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or is suitable for administration twice daily. In some embodiments, about 75 mg of compound a or a pharmaceutically acceptable salt thereof is administered three times daily or is adapted to be administered three times daily. In some embodiments, about 75 mg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times daily. In some embodiments, about 75 mg of compound a or a pharmaceutically acceptable salt thereof is administered five times daily or is adapted to be administered five times daily.

In some embodiments of the methods and compounds of the present disclosure, about 100mg of compound a or a pharmaceutically acceptable salt thereof is administered once daily or is suitable for administration once daily. In some embodiments, about 100mg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or is suitable for administration twice daily. In some embodiments, about 100mg of compound a or a pharmaceutically acceptable salt thereof is administered three times daily or is suitable for administration three times daily. In some embodiments, about 100mg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times daily. In some embodiments, about 100mg of compound a or a pharmaceutically acceptable salt thereof is administered five times daily or is adapted to be administered five times daily.

In some embodiments of the methods and compounds of the present disclosure, about 250mg of compound a or a pharmaceutically acceptable salt thereof is administered once daily or is suitable for administration once daily. In some embodiments, about 250mg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or is suitable for administration twice daily. In some embodiments, about 250mg of compound a or a pharmaceutically acceptable salt thereof is administered three times daily or is suitable for administration three times daily. In some embodiments, about 250mg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times daily. In some embodiments, about 250mg of compound a or a pharmaceutically acceptable salt thereof is administered five times daily or is adapted to be administered five times daily.

In some embodiments of the methods and compounds of the present disclosure, about 25 μ g/kg of compound a or a pharmaceutically acceptable salt thereof is administered once a day or is adapted to be administered once a day. In some embodiments, about 25 μ g/kg mg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or adapted to be administered twice daily. In some embodiments, about 25 μ g/kg mg of compound a or a pharmaceutically acceptable salt thereof is administered three times per day or is adapted to be administered three times per day. In some embodiments, about 25 μ g/kg mg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times per day. In some embodiments, about 25 μ g/kg mg of compound a or a pharmaceutically acceptable salt thereof is administered five times per day or is adapted to be administered five times per day.

In some embodiments of the methods and compounds of the present disclosure, about 50 μ g/kg of compound a or a pharmaceutically acceptable salt thereof is administered once a day or is adapted to be administered once a day. In some embodiments, about 50 μ g/kg mg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or is adapted to be administered twice daily. In some embodiments, about 50 μ g/kg mg of compound a or a pharmaceutically acceptable salt thereof is administered three times per day or is adapted to be administered three times per day. In some embodiments, about 50 μ g/kg mg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times per day. In some embodiments, about 50 μ g/kg mg of compound a or a pharmaceutically acceptable salt thereof is administered five times per day or is adapted to be administered five times per day.

In some embodiments of the methods and compounds of the present disclosure, about 75 μ g/kg of compound a or a pharmaceutically acceptable salt thereof is administered once per day or is adapted to be administered once per day. In some embodiments, about 75 μ g/kg mg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or adapted to be administered twice daily. In some embodiments, about 75 μ g/kg mg of compound a or a pharmaceutically acceptable salt thereof is administered three times per day or is adapted to be administered three times per day. In some embodiments, about 75 μ g/kg mg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times per day. In some embodiments, about 75 μ g/kg mg of compound a or a pharmaceutically acceptable salt thereof is administered five times per day or is adapted to be administered five times per day.

In some embodiments of the methods and compounds of the present disclosure, about 100 μ g/kg of compound a or a pharmaceutically acceptable salt thereof is administered once a day or is adapted to be administered once a day. In some embodiments, about 100 μ g/kg mg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or is adapted to be administered twice daily. In some embodiments, about 100 μ g/kg mg of compound a or a pharmaceutically acceptable salt thereof is administered three times per day or is adapted to be administered three times per day. In some embodiments, about 100 μ g/kg mg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times per day. In some embodiments, about 100 μ g/kg mg of compound a or a pharmaceutically acceptable salt thereof is administered five times per day or is adapted to be administered five times per day.

In some embodiments of the methods and compounds of the present disclosure, about 200 μ g/kg of compound a or a pharmaceutically acceptable salt thereof is administered once a day or is adapted to be administered once a day. In some embodiments, about 200 μ g/kg mg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or adapted to be administered twice daily. In some embodiments, about 200 μ g/kg mg of compound a or a pharmaceutically acceptable salt thereof is administered three times per day or is adapted to be administered three times per day. In some embodiments, about 200 μ g/kg mg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times per day. In some embodiments, about 200 μ g/kg mg of compound a or a pharmaceutically acceptable salt thereof is administered five times per day or is adapted to be administered five times per day.

In some embodiments of the methods and compounds of the present disclosure, about 300 μ g/kg of compound a or a pharmaceutically acceptable salt thereof, or suitable for once daily administration is administered once daily. In some embodiments, about 300 μ g/kg mg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or adapted to be administered twice daily. In some embodiments, about 300 μ g/kg mg of compound a or a pharmaceutically acceptable salt thereof is administered three times per day or is adapted to be administered three times per day. In some embodiments, about 300 μ g/kg mg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times per day. In some embodiments, about 300 μ g/kg mg of compound a or a pharmaceutically acceptable salt thereof is administered five times per day or is adapted to be administered five times per day.

In some embodiments of the methods and compounds of the present disclosure, about 500 μ g/kg of compound a or a pharmaceutically acceptable salt thereof is administered once per day or is adapted to be administered once per day. In some embodiments, about 500 μ g/kg mg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or adapted to be administered twice daily. In some embodiments, about 500 μ g/kg mg of compound a or a pharmaceutically acceptable salt thereof is administered three times per day or is adapted to be administered three times per day. In some embodiments, about 500 μ g/kg mg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times per day. In some embodiments, about 500 μ g/kg mg of compound a or a pharmaceutically acceptable salt thereof is administered five times per day or is adapted to be administered five times per day.

In some embodiments of the methods and compounds of the present disclosure, about 1mg/kg of compound a or a pharmaceutically acceptable salt thereof is administered once daily or is suitable for administration once daily. In some embodiments, about 1mg/kg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or is suitable for administration twice daily. In some embodiments, about 1mg/kg of compound a or a pharmaceutically acceptable salt thereof is administered three times per day or is adapted to be administered three times per day. In some embodiments, about 1mg/kg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times per day. In some embodiments, about 1mg/kg of compound a or a pharmaceutically acceptable salt thereof is administered five times per day or is adapted to be administered five times per day.

In some embodiments of the methods and compounds of the present disclosure, about 5mg/kg of compound a or a pharmaceutically acceptable salt thereof is administered once daily or is suitable for administration once daily. In some embodiments, about 5mg/kg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or is suitable for administration twice daily. In some embodiments, about 5mg/kg of compound a or a pharmaceutically acceptable salt thereof is administered three times per day or is adapted to be administered three times per day. In some embodiments, about 5mg/kg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times per day. In some embodiments, about 5mg/kg of compound a or a pharmaceutically acceptable salt thereof is administered five times per day or is adapted to be administered five times per day.

In some embodiments of the methods and compounds of the present disclosure, about 10mg/kg of compound a or a pharmaceutically acceptable salt thereof is administered once daily or is suitable for administration once daily. In some embodiments, about 10mg/kg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or is suitable for administration twice daily. In some embodiments, about 10mg/kg of compound a or a pharmaceutically acceptable salt thereof is administered three times per day or is adapted to be administered three times per day. In some embodiments, about 10mg/kg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times per day. In some embodiments, about 10mg/kg of compound a or a pharmaceutically acceptable salt thereof is administered five times per day or is adapted to be administered five times per day.

In some embodiments of the methods and compounds of the present disclosure, about 20mg/kg of compound a or a pharmaceutically acceptable salt thereof is administered once daily or is suitable for administration once daily. In some embodiments, about 20mg/kg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or is suitable for administration twice daily. In some embodiments, about 20mg/kg of compound a or a pharmaceutically acceptable salt thereof is administered three times per day or is adapted to be administered three times per day. In some embodiments, about 20mg/kg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times per day. In some embodiments, about 20mg/kg of compound a or a pharmaceutically acceptable salt thereof is administered five times daily or is adapted to be administered five times daily.

In some embodiments of the methods and compounds of the present disclosure, about 30mg/kg of compound a or a pharmaceutically acceptable salt thereof is administered once daily or is suitable for administration once daily. In some embodiments, about 30mg/kg of compound a or a pharmaceutically acceptable salt thereof is administered twice daily or is suitable for administration twice daily. In some embodiments, about 30mg/kg of compound a or a pharmaceutically acceptable salt thereof is administered three times per day or is adapted to be administered three times per day. In some embodiments, about 30mg/kg of compound a or a pharmaceutically acceptable salt thereof is administered or adapted to be administered four times per day. In some embodiments, about 30mg/kg of compound a or a pharmaceutically acceptable salt thereof is administered five times per day or is adapted to be administered five times per day.

Pharmaceutical composition

In the case where the compound has sufficient basicity or acidity, a salt of compound a may be used as an intermediate for isolating or purifying compound a. In addition, it may be appropriate to administer compound a as a pharmaceutically acceptable acid or base salt. Examples of pharmaceutically acceptable salts are organic acid addition salts with acids forming physiologically acceptable anions, such as tosylate, mesylate, acetate, citrate, malonate, tartrate, succinate, benzoate, ascorbate, alpha-ketoglutarate and alpha-glycerophosphate. Suitable inorganic salts may also be formed, including hydrochloride, sulfate, nitrate, bicarbonate, and carbonate salts. In some embodiments, compound a is a hydrochloride salt.

Pharmaceutically acceptable salts can be obtained using standard procedures well known in the art, for example by reacting a sufficient basic compound such as an amine with a suitable acid to provide a physiologically acceptable anion. Alkali metal (e.g., sodium, potassium, or lithium) or alkaline earth metal (e.g., calcium) salts of carboxylic acids may also be prepared.

Compound a may be formulated as a pharmaceutical composition and administered to a mammalian host (e.g., a human patient) in a variety of forms suitable for the chosen route of administration, i.e., orally or parenterally, by intravenous, intramuscular, topical, or subcutaneous routes.

Thus, the compounds of the present invention may be administered systemically, e.g., orally, in combination with a pharmaceutically acceptable vehicle, e.g., an inert diluent or an ingestible edible carrier. They may be enclosed in hard or soft shell gelatin capsules, may be compressed into tablets, or may be incorporated directly into the food of the patient's diet. For oral therapeutic administration, the active compound may be combined with one or more excipients and used in the form of ingestible tablets, buccal tablets, troches, capsules, elixirs, suspensions, syrups, wafers, and the like. Such compositions and preparations should contain at least 0.1% of the active compound. The percentage of the composition and formulation may, of course, vary and may suitably be between about 2% to about 60% by weight of a given unit dosage form. The amount of active compound in such therapeutically useful compositions is such that an effective dosage level will be obtained.

Tablets, troches, pills, capsules and the like may also contain the following: binding agents, for example, gum tragacanth, acacia, corn starch or gelatin; excipients, such as dibasic calcium phosphate; disintegrating agents such as corn starch, potato starch, alginic acid, and the like; lubricants, such as magnesium stearate; and a sweetening agent such as sucrose, fructose, lactose or aspartame or a flavoring agent such as peppermint, oil of wintergreen or cherry flavoring may be added. When the unit dosage form is a capsule, it may contain, in addition to materials of the above type, a liquid carrier such as a vegetable oil or polyethylene glycol. Various other materials may be present as coatings or to otherwise modify the physical form of the solid unit dosage form. For example, tablets, pills, or capsules may be coated with gelatin, wax, shellac, or sugar and the like. A syrup or elixir may contain the active compound, sucrose or fructose as a sweetening agent, methyl and propylparabens as preservatives, a dye and flavoring (e.g., cherry or orange flavor). Of course, any material used in preparing any unit dosage form should be pharmaceutically acceptable and substantially non-toxic in the amounts used. In addition, the active compounds may be incorporated into sustained release formulations and devices.

The active compounds can also be administered intravenously or intraperitoneally by infusion or injection. Solutions of the active compound or its salt can be prepared in water, optionally mixed with a non-toxic surfactant. Dispersions can also be prepared in glycerol, liquid polyethylene glycols, triacetin and mixtures thereof and in oils. Under ordinary conditions of storage and use, these preparations contain a preservative to prevent the growth of microorganisms.

Pharmaceutical dosage forms suitable for injection or infusion may comprise sterile aqueous solutions or dispersions or sterile powders containing the active ingredient which are suitable for the extemporaneous preparation of sterile injectable or infusible solutions or dispersions, optionally encapsulated in liposomes. In all cases, the final dosage form should be sterile, fluid, and stable under the conditions of manufacture and storage. The liquid carrier or vehicle can be a solvent or liquid dispersion medium comprising, for example, water, ethanol, polyol (for example, glycerol, propylene glycol, liquid polyethylene glycol, and the like), vegetable oil, nontoxic glyceryl esters, and suitable mixtures thereof. For example, proper fluidity can be maintained by the formation of liposomes, by the use of surfactants, or in the case of dispersions, by the maintenance of the required particle size. Prevention of the action of microorganisms can be achieved by various antibacterial and antifungal agents, for example, parabens, chlorobutanol, phenol, sorbic acid, thimerosal, and the like. In many cases, it will be preferable to include isotonic agents, for example, sugars, buffers or sodium chloride. Prolonged absorption of the injectable compositions can be brought about by the use in the compositions of agents delaying absorption, for example, aluminum monostearate and gelatin.

Sterile injectable solutions are prepared by incorporating the active compound in the required amount in the appropriate solvent with one or more of the other ingredients enumerated above, as required, followed by filtered sterilization. In the case of sterile powders for the preparation of sterile injectable solutions, the preferred methods of preparation are vacuum drying and the freeze-drying technique which yields a powder of the active ingredient plus any additional desired ingredient present in the previously sterile-filtered solution.

For topical administration, the compounds may be applied in pure form, i.e. when they are liquids. However, it is often desirable to administer them to the skin as a composition or formulation in combination with a dermatologically acceptable carrier, which may be solid or liquid.

Useful solid carriers include finely divided solids such as talc, clay, microcrystalline cellulose, silica, alumina and the like. Useful liquid carriers include water, alcohols or glycols or water-alcohol/glycol blends in which the present compounds can be dissolved or dispersed at effective levels, optionally with the aid of non-toxic surfactants. Adjuvants such as fragrances and additional antimicrobial agents may be added to optimize the properties for a given use. The resulting liquid composition may be applied from an absorbent pad, used to impregnate bandages and other dressings, or sprayed onto the affected area using a pump-type or aerosol sprayer.

Thickeners (e.g., synthetic polymers, fatty acids, fatty acid salts and esters, fatty alcohols, modified celluloses or modified mineral materials) can also be used with the liquid carrier to form spreadable pastes, gels, ointments, soaps, and the like, for direct application to the skin of a user.

Examples of useful dermatological compositions useful for delivering compound a to the skin are known in the art; see, for example, Jacquet et al (U.S. Pat. No. 4,608,392), Geria (U.S. Pat. No. 4,992,478), Smith et al (U.S. Pat. No. 4,559,157), and Wortzman (U.S. Pat. No. 4,820,508).

Useful doses of compound a can be determined by comparing their in vitro activity to the in vivo activity in animal models. Methods for extrapolating effective doses in mice and other animals to humans are known in the art; see, for example, U.S. patent No. 4,938,949.

The amount of the compound or active salt or derivative thereof required for use in treatment will vary not only with the particular salt selected, but also with the route of administration, the nature of the condition being treated and the age and condition of the patient and will ultimately be at the discretion of the attendant physician or clinician.

The compounds are suitably formulated in unit dosage form; for example, each unit dosage form contains from 5 to 1000 mg, suitably from 10 to 750 mg, most suitably from 50 to 500 mg of active ingredient. For example, the compounds are formulated in unit dosage forms containing 1mg, 10mg, 20mg or 100mg of the active ingredient per unit dosage form. In one embodiment, the present invention provides a composition comprising compound a formulated into such a unit dosage form.

The desired dose may be present in a single dose per day or in multiple doses per day, for example in two, three, four, five or more doses per day. For example, the compound is administered in unit dosage form at 100mcg per day, 1mg per day, 10mg per day, 20mg per day, or 100mg per day. For example, the compound is administered twice, three times, four times, or five times daily in a unit dosage form of 100 mcg; twice, three times, four times or five times daily in a unit dosage form of 1 mg; twice, three, four or five times daily administration in a unit dosage form of 10 mg; administered twice, three times, four times or five times daily in a unit dosage form of 20 mg; or administered twice, three times, four times or five times daily in a unit dosage form of 100 mg.

The required dose may suitably be presented in a single dose or as divided doses administered at appropriate intervals, for example as two, three, four or more sub-doses per day. The sub-dose itself may be further divided into, for example, a number of discrete loosely spaced administrations; such as multiple inhalations from an insufflator or by applying multiple drops into the eye.

Test for measuring Activity

The pharmacological properties of a compound can be determined using models well known in the art. In cell culture, binding was competed (Oliver, H.et al (1951) J. biol. chem. 193, 265- "275; Werling, L.L. et al (1985) J. Pharmacol. exp. Ther. 233, 722-" 728), Ca²⁺Release testAssay (Waldhoer, M. et al (2005) Proc. Natl. Acad. Sci. 102, 9050-³⁵S]The GTP γ S assay (in Mulleny, I (1999) in Signal Transmission: A practical assay, 2 nd edition, Oxford University Press, 100-101) can be used to evaluate the affinity and selectivity of compounds for different opioid receptors.

The properties of the compounds can be determined using models well known in the art or by Selective Nerve Injury (SNI), Sciatic Nerve Ligation (SNL), rodent plantar formalin test, rodent paw incisions, Hargreaves test, Von Frey test, Guinea Pig Ileum (GPI), and rodent tail flick procedures. The compounds are also useful for pharmacological characterization of receptors activated by compound a.

The selective nerve injury model included ligation of two branches of the left or right sciatic nerve (the common fibular and tibial nerves) while leaving the third branch (the sural nerve) intact (decoster I, Woolf CJ.Pain2000 Aug, 87(2): 149-58). Another rodent neuropathic pain model, known as the sciatic nerve ligation model, involves the separation and ligation of ligatures (Chaplan SR, Bach FW, pogrel jw, Chung JM, Yaksh TL) around specific lumbar spinal nerves (e.g., L5 spinal nerve, L6 spinal nerve, or both).J Neurosci Methods1994 Jul, 53(1): 55-63). Nerve damage caused by experiments generated by SNI or SNL models often produces symptoms of neuropathic pain (which includes static, dynamic, and/or mechanical allodynia) (Costigan M, Scholz J, Woolf CJ.Annu Rev Neurosci. 2009,32:1-32. doi: 10.1146/annurev.neuro.051508.135531)。

The plantar formalin test (formalin test) in rodents is an experimental rodent model combining nociceptive, inflammatory and neuropathic pain factors. The formalin test involves injecting diluted (typically 0.5% to 5%) formalin (an aqueous solution of formaldehyde) into the plantar surface of the hind paw of a mouse or rat. This injection produces a characteristic pattern of autonomous, atraumatic behavior that begins within minutes of injection. The first "acute" stage of behavior involves intense paw biting, licking and/or withdrawal and is believed to be caused by nociceptive pain, which is directly activated by formalinPain caused by nociceptors. This first phase typically lasts 5 to 10 minutes before the row subsides. Subsequent stages like intense nocifensive behavior were observed after the first stage, and typically between 10 and 60 minutes after formalin injection. Second-stage nociceptive responses may be caused by spontaneous activation of central (spinal cord) nociceptors secondary to intense peripheral activation, similar in some respects to how neuropathic pain is thought to develop, and thus serve as a screening test for molecules that predict the potential for neuropathic pain-relieving properties in humans (Vissers, KC et al)Pharmacol Biochem Behav2006 Jul, 84(3) 479-86). Drugs known to reverse human neuropathic pain often reduce the number of nociceptive behaviors observed in the second phase of the formalin test.

The rodent paw incision model involves making a surgical incision on the plantar surface of the hind paw of a mouse or rat, suturing the closed incision, and then testing the area adjacent the wound for changes in sensory perception, such as allodynia or hypersensitivity, at some point after the incision (usually after 24 hours) (Brennan TJ et al,Pain1996 Mar, 64(3): 493-. Thermal (Hargreaves) and mechanical (von Frey) sensory tests were performed on the plantar region near the incision, 24 hours before and after the surgical incision of the plantar surface of the left hind paw of a laboratory rat.

Hargreaves test: in the context of experimentally induced inflammatory pain, as described previously (Hargreaves K, Dubner R, Brown F, Flores C, Joris J.Pain1988, 32: 77-88) determined the change in the mouse withdrawal threshold upon application of radiant heat stimulation to the plantar surface of the hind paw.

Infrared thermal stimulation was applied to the plantar surface of the hind paw of the experimental rat to test the latency of voluntary foot withdrawal before and after the plantar incision. In the presence of surgical inflammation, the paw withdrawal latency is typically shortened, and this latency is typically reversed by treatment with a clinically effective analgesic.

Von Frey test: the change in mechanically induced pain-related behavior was detected by first placing the rat in a transparent chamber with a wire mesh bottom. After habituation to the chamber, a "von Frey" filament is manually applied to the plantar surface of the hind paw with sufficient force to cause the filament to bend. The force required to bend the filament is calibrated by its stiffness. The reduction in the force required to cause voluntary paw withdrawal will be used as a surrogate measure of mechanical allodynia caused by injury.

The invention will now be illustrated by the following non-limiting examples.

Examples