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A personalised CAR T-cell therapy made by genetically modifying a patient’s own T cells to recognise CD19. It is licensed for adults whose B-cell precursor acute lymphoblastic leukaemia has returned or not responded to treatment.
Obeticholic acid is a prescription farnesoid X receptor (FXR) agonist used for adults with primary biliary cholangitis. It may be used with ursodeoxycholic acid when the response is inadequate, or alone when ursodeoxycholic acid cannot be tolerated.
Obinutuzumab is a monoclonal antibody that targets CD20 on B lymphocytes. In the UK, it is used for certain adults with chronic lymphocytic leukaemia, follicular lymphoma or active lupus nephritis, usually alongside other treatments.
Ocrelizumab is a monoclonal antibody for adults with active relapsing forms of multiple sclerosis and selected early primary progressive multiple sclerosis. It targets certain B cells to reduce inflammatory disease activity but does not cure MS.
Octocog alfa is a recombinant form of clotting factor VIII. It temporarily replaces the factor VIII missing in haemophilia A, helping treat bleeding and prevent future bleeds.
Octreotide is a synthetic version of somatostatin, a hormone that limits release of growth hormone and several digestive-system hormones. This prolonged-release product is used to maintain control of acromegaly in adults who have already responded to and tolerated a somatostatin analogue.
Octreotide acetate is a synthetic version of somatostatin. It suppresses selected hormones and digestive secretions to help control acromegaly, hormone-related tumour symptoms and certain pituitary or neuroendocrine tumours.
Odevixibat sesquihydrate is an ileal bile acid transporter inhibitor that acts mainly within the intestine. It is used under specialist supervision for progressive familial intrahepatic cholestasis and cholestatic itching associated with Alagille syndrome in patients aged 6 months or older.
Conjugated oestrogens are a mixture of oestrogen hormones used as systemic hormone replacement therapy. They replace declining oestrogen after menopause, helping relieve deficiency symptoms and, in selected postmenopausal women, prevent osteoporosis.
Ofatumumab is a monoclonal antibody that targets CD20-positive B cells involved in multiple sclerosis inflammation. It is a specialist disease-modifying treatment for adults with active relapsing forms of multiple sclerosis and aims to reduce future disease activity rather than relieve symptoms immediately.
Ofloxacin is a fluoroquinolone antibiotic available as tablets and eye drops. Tablets treat selected susceptible bacterial infections when other commonly recommended antibiotics are inappropriate; eye drops treat susceptible external eye infections.
Olanzapine is an antipsychotic used mainly for schizophrenia and manic episodes associated with bipolar disorder. It can also help prevent further bipolar episodes after mania has responded to treatment.
Olanzapine pamoate monohydrate is a long-acting injectable antipsychotic used to maintain treatment in adults with schizophrenia who have responded to and tolerated oral olanzapine.
Olezarsen sodium is a liver-targeted antisense treatment that lowers apolipoprotein C-III and triglycerides. In the UK, it is licensed alongside dietary management for adults with genetically confirmed familial chylomicronaemia syndrome.
Olipudase alfa is a replacement form of acid sphingomyelinase, an enzyme that is deficient in acid sphingomyelinase deficiency (ASMD). It is used in adults and children with type A/B or type B disease to treat manifestations outside the central nervous system.
This is a sterile fat emulsion given into a vein as part of parenteral nutrition. It supplies energy and essential fatty acids when adequate nutrition cannot be taken or absorbed through the digestive system.
Olmesartan medoxomil is an angiotensin receptor blocker used to lower high blood pressure. It relaxes blood vessels by reducing the effects of angiotensin II.
An inhaled long-acting beta2 agonist that relaxes airway muscle. It is used for maintenance treatment of COPD in adults, not for sudden breathlessness or asthma.
A combination inhaler containing two long-acting bronchodilators, tiotropium and olodaterol. It is used for maintenance treatment to relieve symptoms of chronic obstructive pulmonary disease (COPD) in adults and is not a rescue inhaler for sudden breathlessness.
Olopatadine hydrochloride is an antiallergic eye treatment with antihistamine and mast-cell-stabilising effects. The selected product is licensed for seasonal allergic conjunctivitis in adults, helping relieve itchy, watery, red or inflamed eyes.
Omalizumab is a biological treatment that binds immunoglobulin E (IgE), an antibody involved in allergic inflammation. It is used as an add-on treatment for selected people whose severe allergic asthma, severe nasal polyps or chronic spontaneous urticaria remain inadequately controlled.
Omaveloxolone is an oral treatment that activates the Nrf2 pathway, which helps cells respond to oxidative stress. In the UK, it is licensed to treat Friedreich’s ataxia in adults and adolescents aged 16 years and older.
Omega-3-acid ethyl esters 90 is a purified mixture containing the omega-3 fatty acids EPA and DHA as ethyl esters. The selected products are used alongside dietary measures to lower certain raised blood triglyceride levels when diet alone has not produced an adequate response.
Omeprazole is a proton pump inhibitor (PPI) that reduces stomach acid. It is used for reflux and acid-related ulcers, including ulcer prevention in some people taking NSAIDs and with antibiotics for Helicobacter pylori infection.
Onasemnogene abeparvovec is an AAV9-based gene therapy that delivers a functional copy of the SMN1 gene. It is used for specified forms of genetically confirmed 5q spinal muscular atrophy and is administered in a specialist clinical centre.
Ondansetron is an anti-sickness treatment that blocks serotonin signals involved in nausea and vomiting. Oral products are mainly used around cancer treatment and surgery, with licensed uses varying by product and age.
Ondansetron hydrochloride dihydrate is the salt form of ondansetron, an anti-sickness treatment. In selected UK products, it is mainly used to prevent or manage nausea and vomiting associated with cancer treatment or surgery.
Opicapone is a catechol-O-methyltransferase (COMT) inhibitor used alongside levodopa-based treatment for Parkinson’s disease. It helps levodopa remain effective for longer when symptoms return near the end of a levodopa dose.
Opium tincture is an oral extract of raw opium containing morphine and other opium alkaloids. The selected UK product is licensed for symptomatic treatment of severe diarrhoea in adults when other anti-diarrhoea treatments have not worked sufficiently.
Oritavancin diphosphate is an intravenous antibiotic active against susceptible Gram-positive bacteria. It is used for acute bacterial infections of the skin and underlying tissues and is generally selected with specialist antimicrobial input.
Orlistat is a locally acting gastrointestinal lipase inhibitor used to support weight loss in adults with obesity, or overweight adults with associated risk factors. It is used alongside a nutritionally balanced, reduced-calorie diet and physical activity.
Orphenadrine hydrochloride is an antimuscarinic treatment used to relieve symptoms of parkinsonism, such as stiffness, tremor and slowed movement. The selected UK product is also licensed for parkinsonism caused by medicines, including neuroleptics.
Oseltamivir is a prescription-only oral antiviral active against influenza A and B. It is used in selected circumstances to treat influenza or prevent it after exposure; it does not replace influenza vaccination.
Oseltamivir phosphate is a prescription antiviral used to treat influenza and, in selected circumstances, prevent influenza after exposure.
Osimertinib is a targeted tyrosine kinase inhibitor for adults with non-small-cell lung cancer containing particular EGFR mutations. It may be used after tumour removal, after chemoradiotherapy, or for advanced disease, alone or with specified chemotherapy.
Ospemifene is a non-hormonal selective oestrogen receptor modulator (SERM). It is used after menopause to treat moderate to severe vulval and vaginal atrophy, including dryness, irritation and pain during sex.
Oxaliplatin is a platinum-based cytotoxic chemotherapy, usually combined with fluorouracil and folinic acid for colorectal cancer.
Oxazepam is a benzodiazepine that reduces activity in the brain and can cause sedation. The selected product is licensed for short-term relief of anxiety that is disabling or causes unacceptable distress, including anxiety associated with insomnia or other illness.
Oxcarbazepine is an anti-seizure medicine used to control focal seizures, including those that become bilateral tonic-clonic seizures. Selected UK products are licensed for use alone or alongside another anti-seizure medicine in adults and children aged 6 years and over.
Oxerutins is a systemic vasoprotective bioflavonoid that acts on small blood vessels. It is used to relieve leg and ankle swelling associated with chronic venous insufficiency.
Oxybuprocaine hydrochloride is a local anaesthetic eye drop that temporarily numbs the eye surface. An eye-care professional uses it during examinations and minor procedures.
Oxybutynin hydrochloride is an antimuscarinic that relaxes the bladder muscle. It is mainly used to reduce urinary urgency, frequency and urge incontinence; selected products also cover certain childhood bladder disorders and specialist intravesical treatment of neurogenic detrusor overactivity.
Oxycodone hydrochloride is a strong opioid painkiller used when pain requires opioid treatment. Some UK product licences also cover moderate to severe cancer-related or post-operative pain.
Oxytocin is a synthetic version of a natural hormone that makes the womb contract. In hospital, it is mainly used to start or strengthen labour and to prevent or treat heavy bleeding after birth.
Ozanimod hydrochloride is an immunomodulator that limits movement of certain lymphocytes from lymphoid tissue into the circulation. It is licensed for selected adults with active relapsing-remitting multiple sclerosis or moderately to severely active ulcerative colitis.