Drug Action
Dasabuvir is a non-nucleoside inhibitor of hepatitis C virus polymerase NS5B, which is an essential component of the hepatitis C virus replication process.
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Drug reference
Dasabuvir is a non-nucleoside inhibitor of hepatitis C virus polymerase NS5B, which is an essential component of the hepatitis C virus replication process.
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Chronic hepatitis C infection of genotype 1, in combination with other antiviral drugs (ombitasvir with paritaprevir and ritonavir, with or without ribavirin) ▶BY MOUTH ▶Adult: 250 mg twice daily for details of duration of treatment, consult product literature, dose to be taken in the morning and evening
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HIV co-infection without suppressive antiretroviral therapy
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Retreatment—efficacy not established
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NICE decisions ▶Ombitasvir with paritaprevir and ritonavir with or without dasabuvir for treating chronic hepatitis C (November 2015) NICE TA365 Dasabuvir (Exviera ®), in combination with ombitasvir with paritaprevir and ritonavir p. 662, is recommended, within its marketing authorisation, as an option for treating genotype 1 or 4 chronic hepatitis C in adults only if the manufacturer provides it with the discount agreed in the patient access scheme. www.nice.org.uk/guidance/ta365
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MHRA/CHM ADVICE: DIRECT-ACTING ANTIVIRALS TO TREAT CHRONIC HEPATITIS C: RISK OF INTERACTION WITH VITAMIN K ANTAGONISTS AND CHANGES IN INR (JANUARY 2017) A EU-wide review has identified that changes in liver function, secondary to hepatitis C treatment with direct- acting antivirals, may affect the efficacy of vitamin K antagonists; the MHRA has advised that INR should be monitored closely in patients receiving concomitant treatment. MHRA/CHM ADVICE: DIRECT-ACTING ANTIVIRAL INTERFERON- FREE REGIMENS TO TREAT CHRONIC HEPATITIS C: RISK OF HEPATITIS B REACTIVATION (JANUARY 2017) An EU-wide review has concluded that direct-acting antiviral interferon-free regimens for chronic hepatitis C can cause hepatitis B reactivation in patients co-infected with hepatitis B and C viruses; the MHRA recommends to screen patients for hepatitis B before starting treatment—patients infected with both hepatitis B and C viruses must be monitored and managed according to current clinical guidelines. MHRA/CHM ADVICE: DIRECT-ACTING ANTIVIRALS FOR CHRONIC HEPATITIS C: RISK OF HYPOGLYCAEMIA IN PATIENTS WITH DIABETES (DECEMBER 2018) Rapid reduction in hepatitis C viral load during direct- acting antiviral therapy for hepatitis C may improve glucose metabolism in patients with diabetes and result in symptomatic hypoglycaemia if diabetic treatment is continued at the same dose. The MHRA advises healthcare professionals: . to monitor glucose levels closely in patients with diabetes during direct-acting antiviral therapy for hepatitis C, especially within the first 3 months of treatment and modify diabetic medication or doses when necessary; . to be vigilant for changes in glucose tolerance and advise patients of the risk of hypoglycaemia; . to inform the healthcare professional in charge of the diabetic care of the patient when direct-acting antiviral therapy is initiated.
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→Appendix 1: dasabuvir
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▶Common or very common Anaemia. asthenia. insomnia. nausea. pruritus ▶Rare or very rare Angioedema ▶Frequency not known Depression. suicidal ideation SIDE-EFFECTS, FURTHER INFORMATION Side-effects listed are reported when dasabuvir is used in combination with Viekirax (ombitasvir with paritaprevir and ritonavir), with or without ribavirin.
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Manufacturer advises avoid—no information available.
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Manufacturer advises avoid—present in milk in animal studies.
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Manufacturer advises caution in cirrhosis —monitor for signs and symptoms of hepatic decompensation and assess hepatic function (including direct bilirubin) at baseline, during the first 4 weeks of treatment and thereafter as clinically indicated, discontinue if hepatic decompensation develops; avoid in moderate to severe impairment.
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There can be variation in the licensing of different medicines containing the same drug. Tablet CAUTIONARY AND ADVISORY LABELS 3, 21, 25 ▶Exviera (AbbVie Ltd) A Dasabuvir (as Dasabuvir sodium monohydrate) 250 mg Exviera 250mg tablets | 56 tablet P £933.33 6.4 Herpesvirus infections Herpesvirus infections Herpes simplex and varicella–zoster infection The two most important herpesvirus pathogens are herpes simplex virus (herpesvirus hominis) and varicella–zoster virus. Herpes simplex infections Herpes infection of the mouth and lips and in the eye is generally associated with herpes simplex virus serotype 1 (HSV-1); other areas of the skin may also be infected, especially in immunodeficiency. Genital infection is most often associated with HSV-2 and also HSV-1. Treatment of herpes simplex infection should start as early as possible and usually within 5 days of the appearance of the infection. In individuals with good immune function, mild infection of the eye (ocular herpes) and of the lips (herpes labialis or cold sores) is treated with a topical antiviral drug. Primary herpetic gingivostomatitis is managed by changes to diet and with analgesics. Severe infection, neonatal herpes infection or infection in immunocompromised individuals requires treatment with a systemic antiviral drug. Primary or recurrent genital herpes simplex infection is treated with an antiviral drug given by mouth. Persistence of a lesion or recurrence in an immunocompromised patient may signal the development of resistance. Specialist advice should be sought for systemic treatment of herpes simplex infection in pregnancy. Varicella-zoster infections Regardless of immune function and the use of any immunoglobulins, neonates with chickenpox should be treated with a parenteral antiviral to reduce the risk of severe disease. Oral therapy in children is not recommended as absorption is variable. Chickenpox in otherwise healthy children between 1 month and 12 years is usually mild and antiviral treatment is not usually required. Chickenpox is more severe in adolescents and adults than in children; antiviral treatment started within 24 hours of the onset of rash may reduce the duration and severity of symptoms in otherwise healthy adults and adolescents. Infection Antiviral treatment is generally recommended in immunocompromised patients and those at special risk (e.g. because of severe cardiovascular or respiratory disease or chronic skin disorder); in such cases, an antiviral is given for 10 days with at least 7 days of parenteral treatment. Pregnant women who develop severe chickenpox may be at risk of complications, especially varicella pneumonia. Specialist advice should be sought for the treatment of chickenpox during pregnancy. Those who have been exposed to chickenpox and are at special risk of complications may require prophylaxis with varicella-zoster immunoglobulin (see under Disease Specific Immunoglobulins). In herpes zoster (shingles) systemic antiviral treatment can reduce the severity and duration of pain, reduce complications, and reduce viral shedding. Treatment with the antiviral should be started within 72 hours of the onset of rash and is usually continued for 7–10 days. Immunocompromised patients at high risk of disseminated or severe infection should be treated with a parenteral antiviral drug. Chronic pain which persists after the rash has healed (postherpetic neuralgia) requires specific management. Choice Aciclovir p. 670 is active against herpesviruses but does not eradicate them. Uses of aciclovir include systemic treatment of varicella–zoster and the systemic and topical treatment of herpes simplex infections of the skin and mucous membranes. It is used by mouth for severe herpetic stomatitis. Aciclovir eye ointment is used for herpes simplex infections of the eye; it is combined with systemic treatment for ophthalmic zoster. Famciclovir p. 672, a prodrug of penciclovir, is similar to aciclovir and is licensed for use in herpes zoster and genital herpes. Valaciclovir p. 673 is an ester of aciclovir, licensed for herpes zoster and herpes simplex infections of the skin and mucous membranes (including genital herpes); it is also licensed for preventing cytomegalovirus disease following solid organ transplantation. Famciclovir or valaciclovir are suitable alternatives to aciclovir for oral lesions associated with herpes zoster. Valaciclovir once daily may reduce the risk of transmitting genital herpes to heterosexual partners—specialist advice should be sought. Foscarnet sodium p. 676 is used for mucocutaneous herpes simplex virus infection unresponsive to aciclovir in immunocompromised patients; it is toxic and can cause renal impairment. Inosine pranobex p. 670 has been used by mouth for herpes simplex infections; its effectiveness remains unproven. Cytomegalovirus infection Ganciclovir p. 674 is related to aciclovir but it is more active against cytomegalovirus (CMV); it is also much more toxic than aciclovir and should therefore be prescribed only when the potential benefit outweighs the risks. Ganciclovir is administered by intravenous infusion for the initial treatment of CMV infection. Ganciclovir causes profound myelosuppression when given with zidovudine p. 692; the two should not normally be given together particularly during initial ganciclovir therapy. The likelihood of ganciclovir resistance increases in patients with a high viral load or in those who receive the drug over a long duration. Valaciclovir is licensed for prevention of cytomegalovirus disease following renal transplantation. Letermovir p. 676 is licensed for prevention of CMV reactivation and disease in recipients of an allogeneic haematopoietic stem cell transplant who are seropositive for the human cytomegalovirus. It should be initiated by a specialist. Valganciclovir p. 675 is an ester of ganciclovir which is Infection licensed for the initial treatment and maintenance treatment of CMV retinitis in acquired immunodeficiency syndrome (AIDS) patients. Valganciclovir is also licensed for preventing CMV disease following solid organ transplantation from a cytomegalovirus-positive donor. Cidofovir p. 674 is licensed in combination with probenecid for the specialist treatment of CMV retinitis in adult AIDS patients. It should be used only when other medicinal products are considered unsuitable. Foscarnet sodium is also active against cytomegalovirus; it is toxic and can cause renal impairment. See local treatment of CMV retinitis. ANTIVIRALS › INOSINE COMPLEXES
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Missed doses If a dose is more than 6 hours late, the missed dose should not be taken and the next dose should be taken at the normal time.
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250 mg twice daily for details of duration of
First-line fragment. Read the complete Indications and Dose section above.
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