Top Prolific, Lyme-Literate Doctor Offers Synthetic Anti-Inflammation Options, but His 16th Book on These Infections Focuses on Natural Options

This is a book on Natural Medicine.

But here are Synthetic Options

Top and Emerging Synthetic Anti-Inflammatory Drugs

Small-molecule pharmaceuticals; biologic monoclonal antibodies are excluded. I have separated established agents from newer/emerging targeted molecules. Ranking is approximate because potency and usefulness depend heavily on the disease. JAK/TYK2, PDE4, BTK, NLRP3 and RIPK1 inhibition are among the most important areas of current small-molecule anti-inflammatory development.

A. Established / Clinically Used Synthetic Anti-Inflammatory Drugs

1. Prednisone / Prednisolone — glucocorticoid

Very broad anti-inflammatory action through the glucocorticoid receptor, suppression of NF-κB/AP-1 and numerous inflammatory cytokines.

_{Reference 1. Strehl C, Ehlers L, Gaber T, Buttgereit F. Glucocorticoids—all-rounders tackling the versatile players of the immune system. Frontiers in Immunology. 2019;10:1744. doi:10.3389/fimmu.2019.01744.}

2. Dexamethasone — potent long-acting glucocorticoid

Extremely potent transcriptional suppression of inflammatory mediators.

_{Reference 2. Cain DW, Cidlowski JA. Immune regulation by glucocorticoids. Nature Reviews Immunology. 2017;17(4):233-247. doi:10.1038/nri.2017.1.}

3. Methylprednisolone — glucocorticoid

_{Reference 3. Buttgereit F, da Silva JAP, Boers M, et al. Standardised nomenclature for glucocorticoid dosages and glucocorticoid treatment regimens: current questions and tentative answers in rheumatology. Annals of the Rheumatic Diseases. 2002;61(8):718-722. doi:10.1136/ard.61.8.718.}

4. Triamcinolone Acetonide — glucocorticoid

_{Reference 4. Najm A, Alunno A, Mariette X, et al. Efficacy of intra-articular corticosteroid injections in knee osteoarthritis: a systematic review and meta-analysis of randomized controlled trials. Joint Bone Spine. 2021;88(4):105198.}

5. Budesonide — locally acting glucocorticoid

High local anti-inflammatory activity with extensive first-pass metabolism.

_{Reference 5. Lichtenstein GR, Loftus EV Jr, Isaacs KL, Regueiro MD, Gerson LB, Sands BE. ACG clinical guideline: management of Crohn’s disease in adults. American Journal of Gastroenterology. 2018;113(4):481-517. doi:10.1038/ajg.2018.27.}

6. Hydrocortisone — corticosteroid

_{Reference 6. Rhen T, Cidlowski JA. Antiinflammatory action of glucocorticoids—new mechanisms for old drugs. New England Journal of Medicine. 2005;353(16):1711-1723. doi:10.1056/NEJMra050541.}

7. Celecoxib — selective COX-2 inhibitor

_{Reference 7. Nissen SE, Yeomans ND, Solomon DH, et al. Cardiovascular safety of celecoxib, naproxen, or ibuprofen for arthritis. New England Journal of Medicine. 2016;375(26):2519-2529. doi:10.1056/NEJMoa1611593.}

8. Diclofenac — COX-1/COX-2 inhibitor

_{Reference 8. da Costa BR, Reichenbach S, Keller N, et al. Effectiveness of non-steroidal anti-inflammatory drugs for the treatment of pain in knee and hip osteoarthritis: a network meta-analysis. Lancet. 2017;390(10090). doi:10.1016/S0140-6736(17)31744-0.}

9. Naproxen — nonselective NSAID

_{Reference 9. Nissen SE, Yeomans ND, Solomon DH, et al. Cardiovascular safety of celecoxib, naproxen, or ibuprofen for arthritis. New England Journal of Medicine. 2016;375(26):2519-2529. doi:10.1056/NEJMoa1611593.}

10. Ibuprofen — nonselective NSAID

_{Reference 10. Nissen SE, Yeomans ND, Solomon DH, et al. Cardiovascular safety of celecoxib, naproxen, or ibuprofen for arthritis. New England Journal of Medicine. 2016;375(26):2519-2529. doi:10.1056/NEJMoa1611593.}

11. Meloxicam — preferential COX-2 NSAID

_{Reference 11. Noble S, Balfour JA. Meloxicam. Drugs. 1996;51(3):424-430. doi:10.2165/00003495-199651030-00007.}

12. Indomethacin — potent nonselective NSAID

_{Reference 12. Richette P, Doherty M, Pascual E, et al. 2016 updated EULAR evidence-based recommendations for the management of gout. Annals of the Rheumatic Diseases. 2017;76(1):29-42. doi:10.1136/annrheumdis-2016-209707.}

13. Ketorolac — potent short-duration NSAID

_{Reference 13. Strom BL, Berlin JA, Kinman JL, et al. Parenteral ketorolac and risk of gastrointestinal and operative site bleeding: a postmarketing surveillance study. JAMA. 1996;275(5):376-382.}

14. Etoricoxib — highly selective COX-2 inhibitor

_{Reference 14. Cannon CP, Curtis SP, FitzGerald GA, et al. Cardiovascular outcomes with etoricoxib and diclofenac in patients with osteoarthritis and rheumatoid arthritis in the MEDAL programme. Lancet. 2006;368(9549):1771-1781. doi:10.1016/S0140-6736(06)69666-9.}

15. Aceclofenac — NSAID

_{Reference 15. Patel PB, Patel TK. Efficacy and safety of aceclofenac in osteoarthritis: a meta-analysis of randomized controlled trials. European Journal of Rheumatology. 2017;4(1):11-18.}

16. Piroxicam — oxicam NSAID

_{Reference 16. Richy F, Scarpignato C, Lanas A, et al. Efficacy and safety of piroxicam revisited: a global meta-analysis of randomised clinical trials. Pharmacological Research. 2009;60(4):254-263.}

17. Etodolac — preferential COX-2 NSAID

_{Reference 17. Jones RA. Etodolac: an overview of a selective COX-2 inhibitor. Inflammopharmacology. 1999;7(3):269-275.}

18. Nabumetone — nonacidic NSAID prodrug

_{Reference 18. Hedner T, Samulesson O, Währborg P, Wadenvik H, Ung KA, Ekbom A. Nabumetone: therapeutic use and safety profile in the management of osteoarthritis and rheumatoid arthritis. Drugs. 2004;64(20):2315-2343.}

19. Sulindac — NSAID prodrug

_{Reference 19. Todd PA, Sorkin EM. Sulindac: a reappraisal of its pharmacodynamic and pharmacokinetic properties, and therapeutic efficacy. Drugs. 1988;35(3):244-285.}

20. Aspirin / Acetylsalicylic Acid — irreversible COX inhibitor

At anti-inflammatory doses it inhibits prostaglandin synthesis; acetylated COX-2 also participates in pro-resolving lipid-mediator biology.

_{Reference 20. Vane JR, Botting RM. The mechanism of action of aspirin. Thrombosis Research. 2003;110(5-6):255-258. doi:10.1016/S0049-3848(03)00379-7.}

Synthetic Disease-Modifying and Targeted Anti-Inflammatory Agents

21. Methotrexate — conventional synthetic DMARD

_{Reference 21. Cronstein BN, Aune TM. Methotrexate and its mechanisms of action in inflammatory arthritis. Nature Reviews Rheumatology. 2020;16(3):145-154. doi:10.1038/s41584-020-0373-9.}

22. Leflunomide — dihydroorotate-dehydrogenase inhibitor

_{Reference 22. Smolen JS, Kalden JR, Scott DL, et al. Efficacy and safety of leflunomide compared with placebo and sulphasalazine in active rheumatoid arthritis. Lancet. 1999;353(9149):259-266. doi:10.1016/S0140-6736(98)09403-3.}

23. Sulfasalazine — synthetic DMARD / intestinal anti-inflammatory

_{Reference 23. Plosker GL, Croom KF. Sulfasalazine: a review of its use in the management of rheumatoid arthritis. Drugs. 2005;65(13):1825-1849.}

24. Hydroxychloroquine — lysosomal/TLR immunomodulator

_{Reference 24. Schrezenmeier E, Dörner T. Mechanisms of action of hydroxychloroquine and chloroquine: implications for rheumatology. Nature Reviews Rheumatology. 2020;16(3):155-166. doi:10.1038/s41584-020-0372-x.}

25. Tofacitinib — JAK1/JAK3 inhibitor

_{Reference 25. Fleischmann R, Kremer J, Cush J, et al. Placebo-controlled trial of tofacitinib monotherapy in rheumatoid arthritis. New England Journal of Medicine. 2012;367(6):495-507. doi:10.1056/NEJMoa1109071.}

26. Upadacitinib — JAK1-preferential inhibitor

_{Reference 26. Fleischmann R, Pangan AL, Song IH, et al. Upadacitinib versus placebo or adalimumab in patients with rheumatoid arthritis and an inadequate response to methotrexate. Arthritis & Rheumatology. 2019;71(11):1788-1800. doi:10.1002/art.41032.}

27. Baricitinib — JAK1/JAK2 inhibitor

_{Reference 27. Taylor PC, Keystone EC, van der Heijde D, et al. Baricitinib versus placebo or adalimumab in rheumatoid arthritis. New England Journal of Medicine. 2017;376(7):652-662. doi:10.1056/NEJMoa1608345.}

28. Deucravacitinib — allosteric TYK2 inhibitor

_{Reference 28. Armstrong AW, Gooderham M, Warren RB, et al. Deucravacitinib versus placebo and apremilast in moderate to severe plaque psoriasis: efficacy and safety results from the 52-week, randomized, double-blinded, placebo-controlled phase 3 POETYK PSO-1 trial. Journal of the American Academy of Dermatology. 2023;88(1):29-39.}

29. Abrocitinib — JAK1 inhibitor

_{Reference 29. Silverberg JI, Simpson EL, Thyssen JP, et al. Efficacy and safety of abrocitinib in patients with moderate-to-severe atopic dermatitis: a randomized clinical trial. JAMA Dermatology. 2020;156(8):863-873.}

30. Ritlecitinib — JAK3/TEC-family kinase inhibitor

_{Reference 30. King B, Zhang X, Harcha WG, et al. Efficacy and safety of ritlecitinib in adults and adolescents with alopecia areata: a randomised, double-blind, multicentre, phase 2b-3 trial. Lancet. 2023;401(10387):1518-1529.}

JAK inhibitors are clinically important anti-inflammatory small molecules, but members differ meaningfully in JAK selectivity, pharmacology and safety.

31. Filgotinib — selective JAK1 inhibitor

_{Reference 31. Genovese MC, Kalunian K, Gottenberg JE, et al. Effect of filgotinib vs placebo on clinical response in patients with moderate to severe rheumatoid arthritis refractory to disease-modifying antirheumatic drug therapy: the FINCH 2 randomized clinical trial. JAMA. 2019;322(4):315-325. doi:10.1001/jama.2019.9055.}

32. Peficitinib — pan-JAK inhibitor with JAK3 activity

_{Reference 32. Takeuchi T, Tanaka Y, Tanaka S, et al. Efficacy and safety of peficitinib in patients with rheumatoid arthritis and an inadequate response to methotrexate: results of a phase III randomized study. Annals of the Rheumatic Diseases. 2019;78(10):1305-1319.}

33. Apremilast — PDE4 inhibitor

_{Reference 33. Kavanaugh A, Mease PJ, Gomez-Reino JJ, et al. Treatment of psoriatic arthritis in a phase 3 randomised, placebo-controlled trial with apremilast. Annals of the Rheumatic Diseases. 2014;73(6):1020-1026.}

34. Roflumilast — PDE4 inhibitor

_{Reference 34. Calverley PMA, Rabe KF, Goehring UM, Kristiansen S, Fabbri LM, Martinez FJ. Roflumilast in symptomatic chronic obstructive pulmonary disease: two randomised clinical trials. Lancet. 2009;374(9691):685-694. doi:10.1016/S0140-6736(09)61255-1.}

35. Crisaborole — topical PDE4 inhibitor

_{Reference 35. Paller AS, Tom WL, Lebwohl MG, et al. Efficacy and safety of crisaborole ointment, a novel nonsteroidal phosphodiesterase-4 inhibitor for mild-to-moderate atopic dermatitis. Journal of the American Academy of Dermatology. 2016;75(3):494-503.e6.}

36. Difamilast — topical PDE4 inhibitor

_{Reference 36. Saeki H, Baba N, Ito K, et al. Difamilast, a selective phosphodiesterase 4 inhibitor, ointment in paediatric patients with atopic dermatitis: a phase III randomized double-blind vehicle-controlled trial. British Journal of Dermatology. 2022;186(1):40-49.}

37. Topical Roflumilast — PDE4 inhibitor

_{Reference 37. Lebwohl MG, Kircik LH, Moore AY, et al. Effect of roflumilast cream vs vehicle cream on chronic plaque psoriasis: the DERMIS-1 and DERMIS-2 randomized clinical trials. JAMA. 2022;328(11):1073-1084. doi:10.1001/jama.2022.15632.}

38. Ozanimod — sphingosine-1-phosphate S1P1/S1P5 modulator

_{Reference 38. Sandborn WJ, Feagan BG, D’Haens G, et al. Ozanimod as induction and maintenance therapy for ulcerative colitis. New England Journal of Medicine. 2021;385(14):1280-1291. doi:10.1056/NEJMoa2033617.}

39. Etrasimod — selective S1P receptor modulator

_{Reference 39. Sandborn WJ, Vermeire S, Peyrin-Biroulet L, et al. Etrasimod as induction and maintenance therapy for ulcerative colitis: two randomised, double-blind, placebo-controlled phase 3 studies. Lancet. 2023;401(10383):1159-1171.}

40. Fingolimod — S1P receptor modulator

_{Reference 40. Kappos L, Radue EW, O’Connor P, et al. A placebo-controlled trial of oral fingolimod in relapsing multiple sclerosis. New England Journal of Medicine. 2010;362(5):387-401. doi:10.1056/NEJMoa0909494.}

Emerging and Next-Generation Synthetic Anti-Inflammatory Drugs

TYK2/JAK Pathway

41. Zasocitinib / TAK-279 — next-generation allosteric TYK2 inhibitor

Designed for greater TYK2 selectivity than ATP-site JAK inhibitors; being developed for psoriasis and other immune-mediated diseases.

_{Reference 41. Catlett IM, Aras U, Liu Y, et al. Discovery and clinical characterization of TAK-279, a highly selective oral allosteric tyrosine kinase 2 inhibitor. Clinical and Translational Science. 2023;16:1774-1786.}

42. Brepocitinib — TYK2/JAK1 inhibitor

Investigated in dermatomyositis, psoriatic arthritis, hidradenitis and other inflammatory diseases.

_{Reference 42. Paik JJ, Casciola-Rosen L, Shin JY, et al. Study of brepocitinib, a TYK2/JAK1 inhibitor, in dermatomyositis. Arthritis & Rheumatology. 2022;74(12):2020-2030.}

43. Ropsacitinib / PF-06826647 — TYK2/JAK2 inhibitor

_{Reference 43. Forman SB, Pariser DM, Poulin Y, et al. TYK2/JAK2 inhibitor PF-06826647 in plaque psoriasis: a randomized phase 2b study. Journal of the American Academy of Dermatology. 2022;87:333-342.}

44. Ivarmacitinib / SHR0302 — selective JAK1 inhibitor

Investigational/regionally developed oral JAK1 molecule evaluated in inflammatory bowel and dermatologic disease.

_{Reference 44. Danese S, et al. Efficacy and safety of ivarmacitinib in patients with moderate-to-severe active ulcerative colitis: a randomized, double-blind, placebo-controlled phase 2 study. Journal of Crohn’s and Colitis. 2023.}

Brepocitinib and ivarmacitinib have produced encouraging randomized-trial signals in inflammatory bowel disease, although their regulatory status and evidence base differ substantially from established JAK inhibitors.

BTK Inhibitors: A Rapidly Emerging Anti-Inflammatory Class

45. Remibrutinib — highly selective covalent BTK inhibitor

Particularly important for mast-cell/B-cell-driven inflammatory disorders. It became one of the first BTK inhibitors authorized for a non-oncologic inflammatory indication in 2025.

_{Reference 45. Maurer M, Berger W, Giménez-Arnau A, et al. Remibrutinib in chronic spontaneous urticaria: results from a randomized phase 2b study. Journal of Allergy and Clinical Immunology. 2022;150(6):1498-1506.e2.}

46. Rilzabrutinib — reversible covalent BTK inhibitor

Targets B-cell and Fc-receptor signaling; developed in immune thrombocytopenia and inflammatory/autoimmune disease.

_{Reference 46. Kuter DJ, Efraim M, Mayer J, et al. Rilzabrutinib, an oral BTK inhibitor, in immune thrombocytopenia. New England Journal of Medicine. 2022;386(15):1421-1431. doi:10.1056/NEJMoa2110297.}

47. Fenebrutinib — reversible noncovalent BTK inhibitor

One of the leading CNS-penetrant/immune BTK-development programs, particularly in multiple sclerosis.

_{Reference 47. Cohen S, Tuckwell K, Katsumoto TR, et al. Fenebrutinib versus placebo or adalimumab in rheumatoid arthritis: a randomized phase II trial. Arthritis & Rheumatology. 2020;72(9):1435-1446.}

48. Tolebrutinib — CNS-penetrant covalent BTK inhibitor

Developed particularly to target both peripheral B cells and CNS-resident microglia.

_{Reference 48. Reich DS, Arnold DL, Vermersch P, et al. Safety and efficacy of tolebrutinib, an oral brain-penetrant BTK inhibitor, in relapsing multiple sclerosis: a phase 2b randomised trial. Lancet Neurology. 2021;20(9):729-738. doi:10.1016/S1474-4422(21)00237-4.}

49. Evobrutinib — covalent BTK inhibitor

An important proof-of-concept molecule, although later phase-3 results were disappointing; therefore it is scientifically important but less promising clinically than some newer BTK inhibitors.

_{Reference 49. Montalban X, Arnold DL, Weber MS, et al. Placebo-controlled trial of an oral BTK inhibitor in multiple sclerosis. New England Journal of Medicine. 2019;380(25):2406-2417. doi:10.1056/NEJMoa1901981.}

50. Orelabrutinib — covalent BTK inhibitor

_{Reference 50. Zhang B. Orelabrutinib: a novel and highly selective Bruton’s tyrosine kinase inhibitor for the treatment of B-cell malignancies and autoimmune diseases. Drug Design, Development and Therapy. 2021;15:1807-1816.}

BTK inhibition is now one of the most active areas in orally administered anti-inflammatory/immunomodulatory drug development. Current molecules differ markedly in covalency, reversibility, CNS penetration and kinase selectivity.

NLRP3 Inflammasome Inhibitors — Especially Important Emerging Drugs

There is still no FDA-approved direct NLRP3 inhibitor, making this class genuinely investigational rather than established therapy.

51. Dapansutrile / OLT1177 — NLRP3 inhibitor

One of the most clinically advanced direct inflammasome inhibitors; has human data in gout and heart failure.

_{Reference 51. Klück V, Jansen TLTA, Janssen M, et al. Dapansutrile, an oral selective NLRP3 inflammasome inhibitor, for treatment of gout flares: an open-label, dose-adaptive study. Lancet Rheumatology. 2020;2(5). doi:10.1016/S2665-9913(20)30065-5.}

52. Inzomelid — brain-penetrant NLRP3 inhibitor

_{Reference 52. Coll RC, Hill JR, Day CJ, et al. MCC950 directly targets the NLRP3 ATP-hydrolysis motif for inflammasome inhibition. Nature Chemical Biology. 2019;15(6):556-559. doi:10.1038/s41589-019-0277-7.}

53. Selnoflast / RO7486967 — oral NLRP3 inhibitor

_{Reference 53. Mangan MSJ, Olhava EJ, Roush WR, Seidel HM, Glick GD, Latz E. Targeting the NLRP3 inflammasome in inflammatory diseases. Nature Reviews Drug Discovery. 2018;17(8):588-606. doi:10.1038/nrd.2018.97.}

54. NT-0796 — CNS-penetrant NLRP3 inhibitor

_{Reference 54. Zahid A, Li B, Kombe AJK, Jin T, Tao J. Pharmacological inhibitors of the NLRP3 inflammasome. Frontiers in Immunology. 2019;10:2538. doi:10.3389/fimmu.2019.02538.}

55. VTX3232 — CNS-penetrant NLRP3 inhibitor

Being developed particularly for neuroinflammatory and neurodegenerative disorders.

_{Reference 55. Swanson KV, Deng M, Ting JPY. The NLRP3 inflammasome: molecular activation and regulation to therapeutics. Nature Reviews Immunology. 2019;19(8):477-489. doi:10.1038/s41577-019-0165-0.}

56. MCC950 / CRID3 — prototype direct NLRP3 inhibitor

A landmark experimental molecule rather than an approved drug; its chemistry and target engagement helped establish NLRP3 as a druggable inflammatory target.

_{Reference 56. Coll RC, Robertson AAB, Chae JJ, et al. A small-molecule inhibitor of the NLRP3 inflammasome for the treatment of inflammatory diseases. Nature Medicine. 2015;21(3):248-255. doi:10.1038/nm.3806.}

RIPK1 / Necroptosis-Directed Anti-Inflammatory Drugs

57. GSK2982772 — selective RIPK1 inhibitor

_{Reference 57. Weisel K, Scott NE, Tompson DJ, et al. Randomized clinical study of safety, pharmacokinetics, and pharmacodynamics of RIPK1 inhibitor GSK2982772 in healthy volunteers. Pharmacology Research & Perspectives. 2017;5(6). doi:10.1002/prp2.365.}

58. Eclitasertib / SAR443122 — next-generation RIPK1 inhibitor

Currently an important investigational approach to suppress inflammatory signaling and necroptotic tissue injury; clinical efficacy remains unproven.

_{Reference 58. Degterev A, Ofengeim D, Yuan J. Targeting RIPK1 for the treatment of human diseases. Proceedings of the National Academy of Sciences USA. 2019;116(20):9714-9722. doi:10.1073/pnas.1901179116.}

59. ABBV-668 — RIPK1 inhibitor

_{Reference 59. Yuan J, Amin P, Ofengeim D. Necroptosis and RIPK1-mediated neuroinflammation in CNS diseases. Nature Reviews Neuroscience. 2019;20(1):19-33. doi:10.1038/s41583-018-0093-1.}

IRAK4 / Innate-Immune Signaling Inhibitors

60. Zimlovisertib / PF-06650833 — IRAK4 inhibitor

Targets Toll-like-receptor/IL-1-receptor signaling upstream of NF-κB.

_{Reference 60. Danto SI, Shojaee N, Singh RSP, et al. Efficacy and safety of the selective interleukin-1 receptor associated kinase 4 inhibitor PF-06650833 in patients with active rheumatoid arthritis. Arthritis & Rheumatology. 2019;71(Suppl 10).}

61. Emavusertib / CA-4948 — IRAK4/FLT3 inhibitor

Primarily developed in hematologic disease but mechanistically relevant to IRAK4-driven inflammatory signaling.

_{Reference 61. Bahia MS, Kaur M, Silakari P, Silakari O. Interleukin-1 receptor associated kinase inhibitors: potential therapeutic agents for inflammatory- and immune-related disorders. Cellular Signalling. 2015;27(6):1039-1055.}

Additional Emerging Synthetic Anti-Inflammatory Strategies

62. Fostamatinib — SYK inhibitor

_{Reference 62. Weinblatt ME, Kavanaugh A, Genovese MC, Musser TK, Grossbard EB, Magilavy DB. An oral spleen tyrosine kinase inhibitor for rheumatoid arthritis. New England Journal of Medicine. 2010;363(14):1303-1312. doi:10.1056/NEJMoa1000500.}

63. Sovleplenib / HMPL-523 — SYK inhibitor

_{Reference 63. Heidari F, et al. Efficacy and safety of Syk and BTK inhibitors in immune thrombocytopenia: a comprehensive review of emerging evidence. Mediators of Inflammation. 2025:5578929.}

64. Orismilast — next-generation PDE4B/D inhibitor

Designed to retain PDE4 anti-inflammatory efficacy while improving tolerability.

_{Reference 64. Warren RB, Strober B, Lebwohl M, et al. Orismilast, a selective PDE4B/D inhibitor, in patients with moderate-to-severe plaque psoriasis: a randomized phase 2b trial. Journal of the American Academy of Dermatology. 2023.}

65. Mufemilast / Hemay005 — PDE4 inhibitor

_{Reference 65. Li H, et al. Efficacy and safety of Hemay005, a novel phosphodiesterase-4 inhibitor, in patients with moderate-to-severe plaque psoriasis: a randomized phase 2 trial. Journal of Dermatological Treatment. 2023.}

66. Lotamilast / RVT-501 / E6005 — topical PDE4 inhibitor

_{Reference 66. Hanifin JM, Ellis CN, Frieden IJ, et al. OPA-15406, a novel topical phosphodiesterase-4 inhibitor, in the treatment of atopic dermatitis: a randomized phase 2 study. Journal of the American Academy of Dermatology. 2016;75(2):297-305.}

PDE4 remains an active development field. Current reviews identify apremilast, roflumilast and crisaborole as established drugs while orismilast, mufemilast and lotamilast represent newer developmental approaches.

67. Masitinib — tyrosine-kinase inhibitor with mast-cell inflammatory effects

_{Reference 67. Vermersch P, Brieva-Ruiz L, Fox RJ, et al. Masitinib treatment in patients with progressive multiple sclerosis: a randomized phase 3 clinical trial. Neurology Neuroimmunology & Neuroinflammation. 2022;9(3).}

68. Laquinimod — synthetic quinoline-3-carboxamide immunomodulator

_{Reference 68. Comi G, Jeffery D, Kappos L, et al. Placebo-controlled trial of oral laquinimod for multiple sclerosis. New England Journal of Medicine. 2012;366(11):1000-1009. doi:10.1056/NEJMoa1104318.}

69. Dimethyl Fumarate — Nrf2-linked immunomodulatory small molecule

_{Reference 69. Gold R, Kappos L, Arnold DL, et al. Placebo-controlled phase 3 study of oral BG-12 for relapsing multiple sclerosis. New England Journal of Medicine. 2012;367(12):1098-1107. doi:10.1056/NEJMoa1114287.}

70. Diroximel Fumarate — fumarate prodrug

_{Reference 70. Naismith RT, Wundes A, Ziemssen T, et al. Diroximel fumarate demonstrates an improved gastrointestinal tolerability profile compared with dimethyl fumarate in patients with relapsing-remitting multiple sclerosis: EVOLVE-MS-2. CNS Drugs. 2020;34(2):185-196.}

The Most Important Emerging Pathways

From a drug-development perspective, I would currently put the most interesting synthetic anti-inflammatory targets approximately in this order:

NLRP3 → TYK2 → BTK → selective JAK1/JAK3 → RIPK1 → IRAK4 → SYK → next-generation PDE4 → S1P modulation.

The distinction between emerging and established matters. For example, direct NLRP3 inhibition remains investigational with no FDA-approved NLRP3 inhibitor, whereas JAK/TYK2 and PDE4 inhibition already have approved representatives.

One particularly fast-moving class is BTK inhibition: by 2026, remibrutinib and rilzabrutinib had become the first FDA-authorized BTK antagonists for non-oncologic immune indications, while fenebrutinib, tolebrutinib and other BTK inhibitors continue to define how useful this pathway will be across autoimmune and neuroinflammatory disease.

Important safety distinction: corticosteroids, NSAIDs, JAK inhibitors and targeted kinase inhibitors are not interchangeable. NSAIDs can cause GI bleeding, renal injury and cardiovascular toxicity; systemic corticosteroids can cause infection, osteoporosis, diabetes and adrenal suppression; JAK inhibitors carry important boxed or class safety concerns involving serious infection, malignancy, thrombosis and cardiovascular events in selected populations. Investigational NLRP3, RIPK1, IRAK4 and BTK agents should not be treated as clinically established merely because their mechanisms appear powerful.