Treatment of chronic hepatitis C virus infection

Anti-Inflammatory Effects of Amantadine and Memantine: Possible Therapeutics for the Treatment of Covid-19?

We have reviewed current data on the anti-inflammatory effects of amantadine and memantine in clinical and in vivo models of inflammation, and we propose that these effects have potential interest for the treatment of the SARS-CoV-2 infection (COVID-19 disease). To that end, we performed a literature search using the PubMed Database from 1966 up to October 31 2020, crossing the terms “amantadine” and “memantine” with “inflammation” and “anti-inflammatory”. Amantadine and/or memantine have shown anti-inflammatory effects in chronic hepatitis C, in neuroinflammation induced by sepsis and by lipopolysaccharides, experimental models of multiple sclerosis, spinal cord injury, and respiratory diseases. Since the inflammatory response is one of the main pathogenetic mechanisms in the progression of the SARS-CoV-2 infection, anti-inflammatory effects of amantadine and memantine could be hypothetically useful in the treatment of this condition. This potential utility deserves further research.

Emerging viral infections

The past decade has witnessed the emergence of several significant viral pathogens and the further evolution of additional viral pathogens. Transmitted by a variety of differing routes, these organisms have presented substantial intellectual challenges to medicine of the 20th and 21st centuries. As perhaps the benchmark pathogen of the past decade, HIV has provided medicine and society with a most formidable opponent, and one that has yet to be fully conquered. Nonetheless, a variety of additional viral pathogens have also perplexed medicine over the past 10-15 years.

Novel therapies in vasculitis

The vasculitides comprise various clinical and pathological entities which pose a therapeutic challenge in terms of disease control versus drug toxicity. Glucocorticoids are important in most regimens; duration of exposure and dosages can be minimised by the use of cytotoxic drugs and transplant immunosuppressives such as cyclosporin, tacrolimus and mycophenolate mofetil. Among alkylating agents, cyclophosphamide has proven to be highly effective; switching to less toxic antimetabolites, typically methotrexate, for maintenance after achieving disease control is an effective strategy. Plasmapheresis may be considered when pharmacological options are maximised. IVIG infusions are of proven benefit in Kawasaki disease and possible benefit in other vasculitides. Targeting infective aetiologies is the basis of therapies such as lamivudine and vidarabine for hepatitis B associated polyarteritis nodosa as well as ribavarin and IFN-alpha for hepatitis C associated cryoglobinaemic vasculitis. IFN-alpha also has immunomodulatory effect even in non-hepatitis C-associated vasculitis. Trimethoprim-sulphamethoxazole has been used in limited Wegener's granulomatosis. Thalidomide, colchicine and dapsone are miscellaneous agents that have been used in Behcet's disease and cutaneous vasculitis. Anti-lymphocytic monoclonal antibodies have been employed for induction therapy in Wegener's granulomatosis. The tumour necrosis factor inhibitor etanercept is just being explored as a therapeutic agent. Bone marrow and stem cell transplantation may find a role in refractory disease.