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Download Drugs Used in Treatment of Major Rheumatic Diseases. (therapeutic
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Treatment of Major Rheumatic Diseases Dr Tanya Potter Consultant Rheumatologist Aims • 1 To pass your exam • 2 Encourage safe prescribing (and you will remember that have an exam in this also) • Rheumatoid arthritis (RA) or osteoarthritis (OA) most common types seen in clinics (& exams) • Dramatically improved treatments in past 20 yrs Osteoarthritis • most common • 75% people > 70 radiographic OA F: M 2.5:1 Osteoarthritis • • • • Joint space narrowing Osteophytes Subchondral sclerosis Bone cysts Management • Pain relief is key • Seek improvement in joint mobility or walking time – e.g. how long it takes for pt to walk to end of corridor • Quality of life- can use functional measures to see how well person is doing. Use several simple questions: – How well can one button clothes? – Can make own meals everyday? – Gives good reliable data OA - Goals of Treatment • No cure – Meds can improve function by reducing pain • Can limit final impairment • Non-pharmacological and pharmacological Non-pharmacological • Patient education (education leaflets/ websites) – Wt loss (10-15 lb weight loss can reduce pain 100%) – Every lb gained, X four across weight bearing joint – Muscle strengthening important -esp. quads muscle – PT & OT important – Use devices for joint protection (canes, walkers etc…) Drugs • Mild to moderate – Paracetamol; – Topical agents: non steroidals, rubefacients • Moderate to severe – As above, plus – NSAIDs – combination analgesics (paracet +opiods) / Opiods/ Tramadol Paracetamol – Analgesic/ antipyretic – Unknown mechanism of action – combo with opiods better response when can’t use NSAIDs (gu / du/ renal/ warfarin) – Doesn’t alter platelet function (bleeding/ surgery) – Safer for elderly – Caution with chronic liver dz (hepatotoxicity, > 2 gm) – Thrombocytopaenia, neutropaenia rare Tramadol • Centrally acting analgesic – Use in addition to NSAID – Effects mu receptors; Same potency as opiods – Can use as adjunctive therapy – Less opiod SE; esp constipation/ nausea/ vomiting • Balance problems • smaller potential of abuse or dose acceleration, (pt needs more drug in shorter time period) c.f. opiods Strong opiods – Use in pt with limited options • loss of function due to pain • renal or heart disease preventing operation • Select pt carefully – Use during period of disease flare, then decrease use – Limitations • Nausea, vomiting, constipation, ***urinary retention • Chronic use leads to physical dependence – Can use with anti-inflammatory – Lots of choice (short or long acting, patches) NSAIDS • 25 million NSAID prescriptions/ yr in UK • Non selective – – – – – Aspirin Ibuprofen Naproxen Indomethacin Piroxicam • Selective cox 2 inhibiters – – – – Celecoxib Etoricoxib Meloxicam etodolac NSAID risk • How many GI bleed admissions annually in the uk? • What percentage are likely to due to NSAIDs? • How many deaths annually? Upper GI complications • 65,000 emergency upper GI admissions p.a. in UK • 12,000 of these admissions (including 2,230 deaths) attributable to NSAID use • Further 330 attributable deaths occur in community • ~2% of NSAID users admitted annually for GI emergencies GI event may be devoid of warning symptoms Many patients asymptomatic prior to serious NSAIDassociated GI event (bleeding, perforation) n = 141 n = 1,921 19% 58% 42% without symptoms 81% with symptoms prostoglandins NSAIDs: Inhibit cox enzymes Asthma blocked Action • Reduce prostaglandin production- less inflammatory mediators • Unopposed leukotrione action • Antipyretic effects – partly due to a decrease in prostaglandin that is responsible for elevating the hypothalamic set point for temp control in fever COX enzyme • Cyclo-oxygenase (COX) has two forms • COX-1 : protects the stomach lining from harsh acids and digestive chemicals. It also helps maintain kidney function • COX-2 : is produced when joints are inflamed or injured Action • Different NSAID’s inhibit the enzyme by different mechanisms • Aspirin – binds covalently with a serine residue of the enzyme (irreversible) • Ibuprofen/Piroxicam – reversible competitive inhibitors of COX non selective • Paracetamol – acts partly by reducing cytoplasmic peroxidase Older nonselective NSAID’s (Ibuprofen, Naproxen) • Block both COX-1 and COX-2, GI upset, bleeding as well as decreasing inflammation • Advice patients to take them with food or a glass of milk and should avoid alcohol. • Pros: – OTC version of these drugs are inexpensive – Low doses of aspirin taken over long term helps to prevent heart attacks, strokes and bowel cancer • Cons: – GI upset ie nausea, ulcers – Kidney problems from overuse – Interacts with warfarin COX-2 inhibitors (Celecoxib, meloxicam, etorocoxib) • Target only the COX-2 enzyme that stimulates the inflammatory response • Pros : – less likely to cause GI upset compared to the older NSAID’s – longer lasting drug – longer relief – do not thin the blood therefore can consider coprescription with warfarin • Cons: – More expensive compared to traditional NSAID’s – Results not as good as endoscopic drug studies suggest Indications • Commonest use – arthritis ie RA or OA and gout • Back pain, sciatica, sprains and strains and rheumatism • Dental pain • Post op pain • Period pain • Renal/ureteric colic • Fever • migraines CAUTIONS • Elderly • Pregnancy- miscarriage, early closure of ductus arteriosus • Breast feeding • Coagulation defects • Renal, cardiac (heart failure/ hypertension/ IHD) or hepatic impairment Contraindications • Severe heart failure • COX-2 : IHD, stroke, PVD and moderate to severe heart failure • CSM advice – previous or active peptic ulceration • hypersensitivity to aspirin or any NSAID – which includes those in whom attacks of asthma, angioedema, urticaria or rhinitis have been precipitated. SIDE EFFECTS • GI – N&D, dyspepsia bleeding and ulceration, • Hypersensitivity • Headaches, dizziness, nervousness, depression, drowsiness, insomnia, hearing disturbances • Photosensitivity • Fluid retention (heart failure), raise blood pressure • Hepatic damage, pancreatitis • Eye and lung changes (alveolitis) • Stevens-Johnson syndrome & toxic epidermal necrolysis (rare) GI • Similar anti inflammatory effects of selective and non selective NSAIDs • Non selective: – 15-40% dyspepsia, nausea, abdo pain – 10% discontinue – Severe GI toxicity 4.5/100pt years • Selective Cox 2 inhibiters – Similar GI symptoms – < 6% discontinue – Severe toxicity 2.1/100 pt years NNT 42 to prevent 1 serious GI event Cardiovascular toxicity • Increased cardiovascular risk of selective NSAIDs is a problem • unopposed pro-thrombotic effects of COX1-mediated production of thromboxane A2 • Also, coxibs effects on blood pressure and renal function could turn out to be more detrimental than those of conventional NSAIDs. prostoglandins CV risk • It is a real risk ‘APPROVE’ study • Data obscured by clinical trials not recruiting ‘normal pts’ • Data obscured by drug company manipulation of the results of clinical trials • Up to 42% higher risk of MI with selective – 0.6%/yr vs 0.3%/yr All NSAID/ CVS • Rise in BP 3-5mm • Equate with an increase – CCF 10-20% – CVA 20% – Angina 12% Lowest risk of all with naproxen (aspirin like effects) Naproxen • Pain and inflammation in rheumatic disorders • 0.5-1g / day in 1-3 divided doses • In high risk pts, give with PPI • Which one? NSAIDs - past strategies • Enteric Coating • Pro-drugs; hepatic metabolism • Gastro-protective agents:PPIs, misoprostol, H2 blockade OA- Adjunctive therapy • Intra articular steroids plus local anesthetic for joint inflammation • Decrease production of inflammatory mediators • Can last a 3-6 months; use with physio • Probably can be done safely up to four times a year – not too frequently; can effect the cartilage Visco-supplementation • Crosslinked hyaluronic acid polymers • OA (knee) • Intra-articular injections X 3-5 • Change viscosity in joint • Pain relief with improved mobility • Success rate is 50-70% for up to 4-6 months • no systemic SE Visco-supplementation • OA, where physio, weight loss, simple analgesia +/- NSAIDs insufficient • & IA steroids not helpful /not lasting • Awaiting/ unfit for surgery Capcaisin cream • 0.025% preparation (Zacin) • Depletes Substance P from nerve endings • Slow to act (1/12 to max effect) • More effective than topical NSAIDs • May reduce analgesic requirement What are the alternatives? • Cod liver oil & other fishy oils • Evening primrose oil • Borage or Starflower oil • Change in balance of cell membrane fatty acids Alternatives? • Glucosamine 1.5 gram/day – substrate for glucosaminoglycans – Pain relief & mobility • Possible 10-25% analgesic effect • -disease modifier ? • ? Nutrition for cartilage • ? Stimulate metabolism • Vitamin C • Framingham study results show reduced pain OA of knee & hip • may improve integrity of cartilage Gout • Joint inflammation caused by uric acid crystal deposits in the joint space Gout • Primary – Over production (10%) – Under secretion (90%) – Enzyme mutations • Predominantly secondary – Overproduction (mutations, heavy exercise, obesity) – Under excretion severe renal diseases, drugs, alcohol, HBP • 2-17% of population are hyperuricaemic • The higher the uric acid the higher the chance of gout • Self reported adult prevalence of 8/1000 • 2-7M:1F • Increase in blacks may reflect increased rates of hypertension Figure 4 Simplified diagram of uric acid production and excretion 1/3 2/3 1/3 Roddy E et al. (2007) The changing epidemiology of gout Nat Clin Pract Rheumatol 3: 443–449 doi:10.1038/ncprheum0556 2/3 Epidemiology •Middle aged men •Dietary purine consumption •Alcohol •Drugs:Low dose aspirin, diuretics •Inherited metabolic abnormalities Clinical features • Gouty Tophi on pinnae • Olecranon bursitis • Gouty tophi on hands • Gouty nephropathy& stones • Large joint oligoarthritis • 1st metatarsophalangeal joint arthritis‘podagra’ erosions with a punched out appearance Management • Prevent occurrence • Diagnose • Treat acute flare • Reduce risk of further flare • Reduce associated morbidity secondary to HBP, hypercholesterolaemia Aspirate joint • Differential diagnosis monoarthritis? Management of Acute Gout (1) • Goal is to rapidly resolve pain and inflammation • High doses of NSAID used: Naproxen. 500mg bd until the attack has passed Indomethacin, diclofenac, etoricoxib also used Management of Acute gout(2) Alternative to NSAIDs Colchicine inhibits microtubule polymerization by binding to tubulin, inhibition of neutrophil motility and so produces an anti-inflammatory response. Treatment • Colchicine 500mg bd to tds – DO NOT USE BNF DOSE OF COLCHICINE – 2/3 will respond cf 1/3 placebo – peak plasma concentration 1-2 hrs and a half life of 4 hrs – Metabolised by the liver with possible enterohepatic circulation – 20% excreted unchanged in urine – Avoid IV – Good alternative for patients receiving anticoagulants/patients in heart failure (doesn’t induce fluid retention) or those who cannot tolerate NSAIDs for any other reason Side effects colchicine • GI • Haemorrhagic gastroenteritis • Myoneuropathy on prolonged course Acute gout treatment cont. • NSAIDs- take early – Upper limit of usual therapeutic dose – Selective and non selective • Glucocorticoids – Intra-articular – Oral pred – IM pred Management of Chronic Gout(1) • When is gout ‘ chronic’? • Recurrence of acute attacks, presence of tophi, or signs of gouty arthritis may call for preventative treatment. • Urate lowering therapy has been shown to be cost effective in patients with 2/more acute attacks/ year Management of chronic gout • Decision to treat – Number of attacks – The uric acid level – Presence of reversible risk factors – Tophi – Renal impairment Aim to reduce uric acid to below 0.36mmol/l or lower in the presence of tophi Choice of drug • Decrease uric acid production by inhibiting xanthine oxidase – Not used in a history of hypersensitivity • Promote renal excretion of urate: uricosurics – Not useful if decreased GFR or history of renal colic Management of Chronic Gout Allopurinol Allopurinol: 1st line therapy for Chronic Gout Xanthine Oxidase inhibitor Uric acid formation • Not to be started in the acute phase • Start 2-3 weeks following acute phase. • Initiation of allopurinol treatment may trigger acute attackstart with NSAID or colchicine & continue for 1 month after hyperuricaemia is corrected Management of chronic gout Allopurinol Dose • Initial 100mg OD ( Preferably after food) • Then adjusted accordingly to plasma/urinary uric acid levels: • Mild: 100-200mg daily • Moderately severe: 300-600mg dailyDoses> 300mg should be given in • Severe: 700-900mg daily divided doses Management of Chronic Gout Allopurinol ctd Caution: • Hepatic impairment • Renal Impairment • Pregnancy • Breast Feeding Contraindications: • Acute gout! Side effects ( extensive list in BNF) •Rashes: Withdraw therapy(if mild re start but withdraw immediately if reccurs) •Neuropathy •Blood disorders •Renal impairment •Hepatoxicity Uricosurics • High dose aspirin (note low dose retains urate) • Sulfinpyrazone • Probenecid • Benzbromarone – Use colchicine prophylaxis – Slowly increase dose – Alkaline diuresis with water loading and oral bicarb Management of Chronic gout (5)Sulfinpyrazone • • • A uricosuric drug – increases the excretion of uric acid Used instead of allopurinol, or in conjunction. Dose 100-200mg daily, increasing over2-3 weeks to 600mg(rarely 800mg) daily, until serum uric acid levels normal. Cautions: • Hepatic impairment • Renal impairment • Pregnancy Contraindications: • in patients with a history of hypersensitivity to aspirin or any other NSAID—which includes those in whom attacks of asthma, angioedema, urticaria or rhinitis have been precipitated by aspirin or any other NSAIDs) • coagulation defects • Hx of MI/Stroke or PAD • moderate or severe heart failure • active pepticulceration Also address… • • • • • Obesity Triglycerides Alcohol Hypertension Thiazide therapy- consider alternative Questions? RA (& Psoriatic Arthritis) • 600,000 people in UK • many unable to work • 42% registered disabled within 3 years • 80% moderate to severe disability in 20 years Management MDT • Physiotherapy & OT very important – must see early or lose mobility quickly – Range of motion, exercise & how to protect joints • NSAIDs • consider low-dose corticosteriods (suppress symptoms while DMARDSs have time to work) • 5-10% very aggressive disease • 60% moderate • severe disability, co-morbidity, reduced life expectancy, despite conventional therapy • Large burden on hospital & social services, carers • Successful reduction disease progression may reap long term cost savings • e.g. Reduction in need for joint replacement DMARDS: What are they? • Disease -modifying antirheumatic drugs, (used in other chronic inflammatory diseases as well) • DMARDs influence the disease process, unlike NSAIDs which just alleviate symptoms • varying and sometimes poorly understood mechanisms of action • e.g. methotrexate, sulfasalazine, gold compounds, penicillamine, chloroquine and biologic agents- which target the action of TNF alpha Current Treatment – Early & Aggressive • Sulphasalazine, Methotrexate, Cyclosporin, Leflunomide, (IM Gold) • Single or combination Rx RA/ PsA • Others (D-penicillamine, azathioprine, hydroxychloroquine) • More aggressive (cyclophosphamide, mycophenolate) • Any/ all may be ineffective + /or toxic Methotrexate • dihydrofolate reductase inhibitor/ folate antagonist – purine antagonist – dihydrofolate reductase reduces folate to FH4, the latter being an essential co-factor in DNA synthesis) • uses: RA (1st line DMARD), psoriasis (if severe/ resistant to topical treatments), cancer, Crohn’s disease • CI: severe blood disorders, active infections, immunodeficiency, kidney or liver failure, pregnancy (females and males must avoid conception for at least 3/12 after stopping treatment), breastfeeding • cautions: effusions (especially ascites and pleural effusions as these act as ‘storage’ for the drug thereby increasing its toxicity), UC, peptic ulcer, decreased immunity and prophyria • Se: mucositis/ GI upset, myelosuppression, skin reactions. Rarely: pulmonary fibrosis/ pneumonitis, hepatotoxicity, neurotoxicity, seizures, renal failure (due to precipitation of the drug in the renal tubules) • interactions: NSAIDs (caution), trimethoprim, co-trimoxazole. These increase toxicity levels • dose: methotrexate is usually given orally but can be given im or subcut (intrathecally- only in oncology) • 7.5mg once WEEKLY • max 25mg/week. Pre-tx assessment: • FBC, U&E's, creatinine, LFT's, CXR. Monitoring: • FBC fortnightly- until 6/52 after last dose increase, and provided it is stable monthly thereafter. • LFT's fortnightly • U&E's 6-12 monthly (more frequently if there is any reason to suspect deteriorating renal function). • Action to be taken (i.e. discuss with rheumatologist) if: • WBC <4.0x10^9/l, neutrophils<2.0x10^9 • Platelets<150x10^9 /l • >2-fold rise in AST, ALT (from upper limit of reference range) • Unexplained fall in albumin • Rash or oral ulceration • New or increasing dyspnoea or cough • MCV>105fl (investigate and if B12 or folate low start appropriate supplementation) • Significant deterioration in renal function • Abnormal bruising or sore throat • note that in addition to absolute values for haematological indices a rapid fall or a consistent downward trend in any value should prompt caution and extra vigilance. Sulphasalazine (EN) • 1st or 2nd choice in UK; mild to moderate • not teratogenic or strong immunosupressant • Up to three months to take effect • GI SE, elevated LFTs, bone marrow depression • Monitoring bloods 3 monthly • first introduced for antibiotic action in colon, for inflammatory bowel disease. • mode of action unclear - ?anti-inflammatory, immunomodulatory and/or antibacterial Corticosteriods • start early to tide over or adjunct e.g. to MTX • Prednisolone – Modest dose (7.5-10 mg/day) & decrease – Long term dose should not exceed 10 mg/day – Treat acute flares IA IM or IV • SE: – Wt gain, Cushings, bruising, osteoporosis, infection risk – Discontinuation may be difficult Gold therapy • Established> 50 yrs as effective treatment • weekly painful injection for 6/52 then 2-4 /52 • freq lab monitoring; BM suppression; nephritis • Decreases phagocytosis & monocyte activation • Inhibits lymphocyte responses • SE – 35% discontinue – rash & stomatitis – proteinuria – glomerulonephritis Cyclosporin A • Nephrotoxicity espec with NSAIDs • causes hypertension • usually in combination • Azathiaprine • moderate efficacy, three months to reach efficacy • purine antagonist, & interferes with nucleotide synthesis • SEs liver toxicity, bone marrow toxicity, monitoring 3/12 – Cyclosporin & azothiaprine used in 2-5% of pts Leflunomide • pyrimidine antagonist • comparable efficacy to SZP • probably comparable toxicity may be tolerated/ effective where other drugs not suitable after methotrexate, before CyA Mycophenolate Mofetil • Reversible inhibitor inosine monophosphate dehydrogenase • inhibition lymphocyte proliferation/ antibody formation/ adhesion molecule expression • Improved safety cf. other immunosupressants • SLE nephritis;refractory to cyclophosphamide • Scleroderma. • (RA) Biological therapy: Anti-TNFs • anticytokine therapy • specifically target TNF-alpha, which is an important mediator of rheumatoid inflammation • uses: RA, psoriatic arthritis and ankylosing spondylitis • current guidelines (developed by the British Society for Rheumatology in 2003) restrict their use in the UK to patients who fail two or more conventional second-line agents Pre-administration • Disease Activity Score (DAS) of joint count on two occasions (one month apart) before treatment • Pre-tx: bloods (FBC, U&E, LFT, ANA and DNA binding), check for TB, do not administer live vaccines, check cardiac function and demyelinating diseases (b/c these are all side-effects of medication) • for subcutaneous self-administration – assess patient’s ability to self-administer; include training plan Adalimumab, Infliximab & Etanercept • monoclonal antibody against TNF-alpha or fusion protein against soluble TNF alpha • MOA/ a TNF receptor joined to the Fc domain of a human IgG molecule (basically acts to mop up TNF molecules taking them ‘out of circulation’). • CI/ pregnancy, breastfeeding, severe infections. • Severe infections- TB, septicaemia Biological therapy: B-cell depletion, e.g. Rituximab • a monoclonal antibody against CD20 which causes lysis of B-cells • uses/ lymphoma chemotherapy, RA. • used with methotrexate in patients who have had an inadequate response to the anti-TNFs. • MOA/ binds to CD20 molecule on the Bcell. References • www.rheumatology.org.uk • BNF • various pharmacology books and websites.. Psoriatic arthritis • 10% with psoriasis get psoriatic arthritis. • Often asymmetrical inflammatory arthropathy • NSAIDs & Sulphasalazine in early stages, but neither affects the psoriasis. • Methotrexate, CyA & anti-TNF drugs treat both the arthritis & the psoriasis Ankylosing spondylitis • DMARDS dismal in treating axial disease • NSAIDs for pain & stiffness • Exercise & physio • Sulphasalazine, & Methotrexate particularly useful with peripheral disease • Anti-TNF drugs for axial disease Questions? OSTEOPOROSIS • Common, preventable, potentially disabling • Worth treating to prevent further #, & improve quality of life • Primary Care Socioeconomic Costs Osteoporotic Fractures 200,000 osteoporotic fractures each year cost NHS an estimated £1.5 billion • • 1 in 2 women experience a fracture by the age 70. • 1 in 12 men at risk of fracturing due to osteoporosis at some time in their life. D1202 Age Related Changes in Bone Mass1 Attainment of Peak Bone Mass Consolidation Bone Mass Age Related Bone Loss Menopause Men Fracture threshold Women 0 10 20 30 40 50 60 Age (years) 1. Compston JE. Clinical Endocrinology 1990; 33: 653-682. D1202 • Osteopaenia: T score <-1-<2.5 • Osteoporosis ; T score <-2.5 • T score means comparing the pts density to a 25 year old female. Identifying those at risk • Predisposing factors– alcohol, smoking – liver or renal disease – malabsorption, poor Ca intake – Low BMI – thyroid disease, DM, Cushings, hyperparathyroidism – immobility, inflammatory disease, RA – hypogonadism in men Identifying those at risk • drugs – Current or planned long term oral corticosteroid use (>7.5mg prednisolone / day for > 3/12 – Anticonvulsants – heparin Management 1. Patient Education • Lifestyle Changes: Diet Weight bearing exercise Habits: smoking & excess alcohol • Falls Prevention home assessment hip protectors NICE guidance 1 • Primary prevention • Complex • >70 with a risk factor for fracture or an indicator for fracture and t score <-2.5 NICE 2 • Secondary prevention ie at least 1 fracture Ca + vit D • >75yrs bisphosphonate • 65-74 DEXA< and if <2.5 then bisphos • <65 treat if T score < -3, or -2.5 plus a risk factor NICE 3 • Prevention of steroid induced OP: • Lifestyle advice • Ca & vit d • <65 yrs DEXA, bisphosphonate if osteopaenic • >65 bisphosphonate Osteoporosis Pharmacology Bisphosphonates Calcitonin Osteoporosis Raloxifene & Teriparatide Vitamin D Calcium salts Calcium • Indications: Osteoporosis, ↓Ca2+, ↑ PO4 • Contraindications: Conditions associated with ↑Ca2+ • Side effects: GI disturbances, arrhythmias, bradycardia • Interactions: effects potentiated by thiazides and decreased by corticosteroids. Decreases absorption of tetracyclines and biosphosphonates. • In osteoporosis, calcium intake double recommended amount reduces rate of bone loss. • Dose: 400-800mg/ day • Adcal D3 forte, calcichew D3 Forte Vit D • Examples: ergocalciferol, calciferol, cacitriol • Mechanism of action: stimulates absorption of calcium and phosphate from intestine and decreases renal excretion of calcium • Indications: Osteoporosis, CRF, osteomalacia, hypoparathyroidism • Side effects: Vascular calcification, nephrocalcinosis, soft-tissue calcification Bisphosphonates Pharmacology • Alendronate and residronate orally, pamidronate, ibandronate and zoledronate IV • Mechanism of action: inhibit osteoclastic activity. Specifically reduce the resorption and formation of hydroxyapatite crystals. • Indications: postmenopausal osteoporosis, paget’s disease of bone, malignancy-associated hypercalcaemia • Adverse effects: bone pain, osteomalacia (etidronate), oesophagitis, nausea, diarrhea • 70mg alendronate once a week with ca and vit d Raloxifene (Evista) • Selective oestrogen receptor modulator (SERM) treatment / for prevention of postmenopausal osteoporosis • Demonstrates oestrogen agonist activity on bone & partially on cholesterol metabolism, but oestrogen antagonism in uterine and breast tissues. • ? Benefits in stroke and breast cancer reduction Strontium ranelate (Protelos) • granules for oral suspension • treatment of postmenopausal osteoporosis • As good as bisphosponates & well tolerated (even in very elderly) • Increases bone formation & decr bone resorption • Absorption affected by food & milk/derivatives. • Suspension should ideally be given at bedtime, at least two hours after any food drink • cost per month comparable with branded bisphosphonates & raloxifene. Calcitonin • Synthesised and secreted by parafoliicular C cells of thyroid gland • Mechanism of action: decreases osteoclastic bone resorption and calcium and phosphate resorption from kidney. • Indications: osteoporosis, paget’s disease of bone, malignancy-associated hypercalcaemia • Adverse effects: allergic reaction (flushing, redness or tingling of face), nausea, increased urinary frequency • Dose: for postmenopausal osteoporosis: 200 units (1 spray) intranasally teriparatide rDNA (Foresteo) • Synthetic parathyroid hormone; 5X greater BMD in lumbar spine than alendronate after 6/12 • BUT daily injections with 20mg Forteo for 18/12 – Teriparatide 20mcg daily - 1 prefilled pen = £271.88 – Raloxifene 60mg daily = £21.74 – Fosamax once weekly 70mg = £23.12 • stimulates new bone formation Teriperatide cont • animal studies increased incidence osteosarcoma • Can use for secondary prevention if >65 and bisphosphates not helpful and T score <-4 Denosumab • Fully human monoclonab antibody to RANK ligand • RANK is expressed by pre-osteoclasts, and induces their conversion into mature osteoclasts • There for inhibits clasts, reducing bone resorption • Sub cut every 6 months • Cost similar to branded bisphosphonates So • Plenty of hope with new treatments • BUT • Also plenty of • a) COST & • b) scope for causing harm • Questions?
