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This lecture was conducted during the Nephrology Unit Grand Ground by Medical Student rotated under Nephrology Division under the supervision and administration of Prof. Jamal Al Wakeel, Head of Nephrology Unit, Department of Medicine and Dr. Abdulkareem, Al Suwaida, Chairman of the Department of Medicine. Nephrology Division is not responsible for the content of the presentation for it is intended for learning and /or education purpose only. Cyclosporine Presented by: Hatem Al-Nasser Medical Student July 2008 Cyclosporine, the active principle in cyclosporine capsules USP is cyclic polypeptide immunosuppressant agent consisting of 11 amino acids. It is produced as a metabolite by the fungus species Tolypocladium Gams. Each capsule contains the following inactive ingredients: methanol, purified water, sodium lauryl sulfate and talc. Mechanism of action In the cytoplasm, cyclosporine (CsA) binds to its immunophilin, cyclophylin (CpN), forming a complex between cyclosporine and CpN. The cyclosporine–CpN complex binds and blocks the function of the enzyme calcineurin (CaN), which has a serine/threonine phosphatase activity. As a result, CaN fails to dephosphorylate the cytoplasmic component of the nuclear factor of activated T cells (NF-ATc), and thereby the transport of NF-ATc to the nucleus and the binding of NF-ATc to the nuclear component of the nuclear factor of activated T cells (NFATn). The NF-ATc–NF-ATn complex binds to the promoter of the interleukin 2 (IL-2) gene and initiates IL-2 production. Consequently, T cells do not produce IL-2, which is necessary for full Tcell activation. Therefore It inhibits T cell activation Pharmacokinetics: Cyclosporine absorption is incomplete and some what erratic, although a new microemulsion formulation improves its consistency and provides 20-30% bioavailability. Grapefruit juice increases cyclosporine bioavailability by as much as 62%. Cyclosporine is metabolized by CYP3A and consequently is subject to a large number of drug interactions. Indications and contraindications: Cyclosporine capsules USP are indicated for the prophylaxis of organ rejection in kidney, liver, and heart allogeneic transplants. It is always to be used with adrenal corticosteroids. The drug may also be used in the treatment of chronic rejections in patients previously treated with other immunosuppressive agents. It is also indicated in RA, SLE, polymyositis, dermatomyositis, Wegner’s granulomatosis, and juvenile chronic arthritis Cyclosporine is contraindicated in patients with active ocular infections and in patients with known or suspected hypersensitivity to any of the ingredients in the formulation. Side effects and drug interactions: The principal adverse reactions of cyclosporine therapy are renal dysfunction, tremor, hirsutism, hyperkalemia, hepatotoxicity, hypertension, and gum hyperplasia. Hypertension which is usually mild to moderate may occur in 50% of patients following renal transplantation and in most cardiac transplant patients. Rare adverse effects include: anxiety, chest pain, constipation, depression, hair breaking, hematuria, joint pain, lethargy, mouth sores, MI, night sweats, pancreatitis, pruritus, swallowing difficulty, tingling, upper GI bleeding, visual disturbance, weakness, and wight loss. Nephrotoxicity increases when the drug is taken with diltiazem, potassium sparing diuretics and drugs inhibiting CYP3A. Mycophenolate Mofetil ( CellCept ) Mycophenolate is an immunosuppressant drug used to prevent rejection in organ transplantation. It was initially marked as the prodrug mycophenolate mofetil (MMF) to improve oral bioavailability. More recently, the salt mycophenolate sodium has also been introduced. Mycophenolic acid is commonly marketed under the trade names CellCept (mycophenolate mofetil ; Roche) and myfortic (mycophenolate sodium ; Novartis) Mechanism of action: MMF is converted to mycophenolic acid, the active form of the drug. The active product inhibits cytosine monophosphate dehydrogenase and, secondarily, inhibits T cell lymphocyte proliferation; downstream it interferes with leukocyte adhesion to endothelial cells through inhibition of E-selectin, Pselectin, and intercellular adhesion molecule 1. Pharmacokinetics: Mycophenolate is derived from the fungus Penicillum stoloniferum. Mycophenolate mofetil is metabolized in the liver to its active moiety mycophenolic acid. It inhibits inosine monophosphate dehydrogenase, the enzyme that controls the rate of synthesis of guanine monophosphate in the denovo pathway of purine synthesis used in the proliferation of B and T lymphocytes. Mycophenolate is potent and can be in place of the older anti –proliferative azathioprine. It is usually used as a part of a three compound regimen if immunosuppressants, also including a calcineurin inhibitor (Cyclosporine or tacrolimus) and prednisolone. Indications and contraindications: In general, mycophenolate is used for the prevention of organ transplant rejection. Mycophenolate mofetil is indicated for the prevention of organ transplant rejection in adults and renal transplant in children > 2 years; whereas mycophenolate sodium is indicated for the prevention of renal transplantation in adults. Mycophenolate sodium has also been used for the prevention of rejection in liver, heart, and/or lung transplant. It is also utilized as a steroid sparing treatment in immune-mediated disorders including immunoglobulin A nephropathy, small vessel vasculitides, and psoriases. Its increasing application in treating lupus nephritis has demonstrated more frequent complete response and less frequent complications compared to cyclophosphamide bolus therapy, a regimen with risk of bone marrow suppression, infertility, and malignancy. Side effects: The most common side effects with mycophenolate include upset stomach, nausea, vomiting or diarrhea. Other possible side effects include headache, dizziness, difficulty sleeping, tremor and, occasionally, rash. These side effects usually go away with time, but tell a doctor if they persist. Less common but more serious side effects include a reduction of white blood cells (increasing the chances of infections), red blood cells that ferry oxygen to tissues (which may lead to anemia), and platelets that aid clotting (which can lead to gastrointestinal bleeding). Periodic blood tests can detect reduced blood counts early on to avoid these problems. Patients older than 65 may be at increased risk for some side effects, especially infections and gastrointestinal bleeding. People who have had ulcers or other serious gastrointestinal conditions should talk with their doctors before taking this medication. Studies of transplant patients taking mycophenolate have found it may increase risk of some cancers such as lymphomas and skin cancers. Because there may be a similar risk in people with rheumatic conditions who take mycophenolate for long periods of time, use a sunscreen and .avoid prolonged sun exposure Prednisone Prednisone is an oral, synthetic corticosteroid used for suppressing the immune system and inflammation. It mimics the action of cortisol (hydrocortisone), the naturally-occurring corticosteroid produced in the body by the adrenal glands. Corticosteroids have many effects on the body, but the most common are used for their potent anti-inflammatory effects, particularly in those conditions in which the immune system plays an important role. Such conditions include arthritis, colitis, asthma, bronchitis, certain skin rashes, and allergic or inflammatory conditions of the nose and eyes. Prednisone is inactive in the body and, in order to be effective, first must be converted to prednisolone by enzymes in the liver. Therefore, prednisone may not work as effectively in people with liver disease whose ability to convert prednisone to prednisolone is impaired Mechanism of action: Glucocorticoids are naturally occurring hormones that prevent or suppress inflammation and immune responses when administered at pharmacological doses. At a molecular level, unbound glucocorticoids readily cross cell membranes and bind with high affinity to specific cytoplasmic receptors. This binding induces a response by modifying transcription and, ultimately protein synthesis to achieve the steroid's intended action. Such actions may include: inhibition of leukocyte infiltration at the site of inflammation, interference in the function of mediators of inflammatory response, and suppression of humeral immune responses. Some of the net effects include reduction in edema or scar tissue, as well as a general suppression in immune response. The degree of clinical effect is normally related to the dose administered. The anti-inflammatory actions of corticosteroids are thought to involve phospholipase A2 inhibitory proteins, collectively called lipocortins. Lipocortins, in turn, control the biosynthesis of potent mediators of inflammation such as prostaglandins and leukotrienes by inhibiting the release of the precursor molecule arachidonic acid. Likewise, the numerous adverse effectsrelated to corticosteroid use are usually related to the dose .administered and the duration of therapy Pharmacokinetics: Prednisone is rapidly absorbed across the GI membrane following oral administration. Peak effects can be observed after 1—2 hours. The circulating drug binds extensively to the plasma proteins albumin and transcortin, with only the unbound portion of a dose active. Systemic prednisone is quickly distributed into the kidneys, intestines, skin, liver and muscle. Corticosteroids distribute into the breast milk and cross the placenta. Prednisone is metabolized by the liver to the active metabolite prednisolone, which is then further metabolized to inactive compounds. These inactive metabolites, as well as a small portion of unchanged drug, are excreted in the urine. The plasma elimination half-life is 1 hour whereas the biological half-life of prednisone is 18—36 hours Indications: Endocrine disorders: primary or secondary adrenocortical insufficiency (hydrocortisone or cortisone is the first choice; synthetic analogs may be used in conjunction with mineralocorticoids where applicable; in infancy mineralo-corticoid supplementation is of particular importance); congenital adrenal hyperplasia; hypercalcemia .associated with cancer; non-suppurative thyroiditis Rheumatic disorders: as adjunctive therapy for short-term administration (to tide the patient over an acute episode or exacerbation) in: psoriatic arthritis, rheumatoid arthritis, including juvenile rheumatoid arthritis (selected cases may require lowdose maintenance therapy), ankylosing spondylitis, acute and subacute bursitis, acute nonspecific tenosynovitis, acute gouty arthritis, post-traumatic osteoarthritis, synovitis of osteoarthritis, .epicondylitis Collagen diseases: during an exacerbation or as maintenance therapy in selected cases of: systemic lupus erythematosus, systemic dermatomyositis (polymyositis), acute rheumatic carditis Dermatologic diseases: pemphigus; bullous dermatitis herpetiformis; severe erythema multiforme (Stevens-Johnson syndrome); exfoliative dermatitis; mycosis fungoides; severe psoriasis; severe seborrheic dermatitis Allergic states: control of severe or incapacitating allergic conditions intractable to adequate trials of conventional treatment: seasonal or perennial allergic rhinitis; bronchial asthma; contact dermatitis; atopic dermatitis; serum sickness; drug hypersensitivity reactions Ophthalmic diseases: severe acute and chronic allergic and inflammatory processes involving the eye and its adnexa such as: allergic corneal marginal ulcers, herpes zoster ophthalmicus, anterior segment inflammation, diffuse posterior uveitis and choroiditis, sympathetic ophthalmia, allergic conjunctivitis, keratitis, chorioretinitis, optic neuritis, iritis and iridocyclitis Respiratory diseases: symptomatic sarcoidosis; Loeffler’s syndrome not manageable by other means; berylliosis; fulminating or disseminated pulmonary tuberculosis when used concurrently with appropriate antituberculous chemotherapy; aspiration pneumonitis Hematologic disorders: idiopathic thrombocytopenic purpura in adults; secondary thrombocytopenia in adults; acquired (autoimmune) hemolytic anemia; erythroblastopenia (RBC anemia); congenital (erythroid) hypoplastic anemia Neoplastic diseases: for palliative management of: leukemias and lymphomas in adults, acute leukemia of childhood Edematous state: to induce a diuresis or remission of proteinuria in the nephrotic syndrome, without uremia, of the idiopathic type or that due to lupus erythematosus Gastrointestinal diseases: to tide the patient over a critical period of the disease in: ulcerative colitis, regional enteritis Nervous system: acute exacerbations of multiple sclerosis Miscellaneous: tuberculous meningitis with subarachnoid block or impending block when used concurrently with appropriate antituberculous chemotherapy; trichinosis with neurologic or myocardial involvement Contraindications/precautions: abrupt discontinuation breast-feeding cataracts children coagulopathy Cushing's syndrome diabetes mellitus diverticulitis fungal infection GI disease glaucoma heart failure hepatic disease herpes infection hypertension hypothyroidism infection inflammatory bowel disease measles myasthenia gravis myocardial infarction osteoporosis peptic ulcer disease psychosis renal disease seizure disorder surgery thromboembolic disease tuberculosis ulcerative colitis vaccination varicella viral infection visual disturbance Absolute contraindications are in italics Side effects: abdominal pain acne vulgaris adrenocortical insufficiency amenorrhea angioedema anorexia anxiety appetite stimulation arthralgia avascular necrosis bone fractures cataracts constipation Cushing's syndrome depression diabetes mellitus diaphoresis diarrhea dysmenorrhea ecchymosis edema EEG changes emotional lability erythema esophageal ulceration euphoria exfoliative dermatitis exophthalmos fever fluid retention gastritis growth inhibition headache heart failure hirsutism hypercholesterolemia hyperglycemia hypernatremia hypertension hypocalcemia hypokalemia hypotension (HPA) suppression immunosuppression impaired wound healing increased intracranial pressure infection insomnia lethargy menstrual irregularity metabolic alkalosis mood lability myalgia myopathy nausea/vomiting ocular hypertension optic neuritis osteoporosis palpitations pancreatitis papilledema peptic ulcer peripheral neuropathy petechiae phlebitis physiological dependence pseudotumor cerebri psychosis restlessness retinopathy seizures sinus tachycardia skin atrophy sodium retention striae thrombocytopenia thromboembolism thrombosis urinary incontinence urinary urgency urticaria vertigo visual impairment weakness weight gain weight loss withdrawal Thank you Done by: Hatem AL-Nasser