Daclavir60 mg

Daclavir is a direct-acting antiviral (NS5A inhibitor) approved for the treatment of chronic hepatitis C virus (HCV) infection. It is never used as monotherapy.

• FDA-approved use: Daclavir in combination with sofosbuvir, with or without ribavirin, is indicated for chronic HCV genotype 1 or 3 infection in adults.
• Guideline-supported use: Daclavir plus sofosbuvir regimens are also recommended by international HCV treatment guidelines for genotype 2 and 4 infection, and in patients with compensated or decompensated cirrhosis (with ribavirin added in decompensated disease).
• Combination requirement: Daclavir must always be combined with sofosbuvir (and sometimes ribavirin); it has no established antiviral effect when used alone.
• Special populations: Regimens containing Daclavir are used in HIV/HCV coinfected patients under specialist supervision.

Each film-coated tablet contains Daclatasvir (as dihydrochloride) equivalent to 30 mg or 60 mg of daclatasvir base. Tablets also contain standard inactive excipients such as microcrystalline cellulose, lactose monohydrate, croscarmellose sodium, magnesium stearate, and a film-coating agent.

Daclavir is an oral, direct-acting antiviral agent belonging to the NS5A replication complex inhibitor class. It was developed specifically to treat chronic hepatitis C virus infection and is administered only as part of a combination antiviral regimen, most commonly with sofosbuvir. Daclavir is not active against other viruses, including HIV or hepatitis B virus, and does not cure hepatitis B.

Daclavir belongs to the therapeutic class of Direct-Acting Antivirals (DAAs) for hepatitis C, specifically the NS5A inhibitor subclass.

Daclatasvir is a potent inhibitor of the hepatitis C virus NS5A protein, which is essential for both viral RNA replication and virion assembly. By binding to the N-terminus of NS5A, Daclatasvir blocks these two distinct steps of the HCV lifecycle, producing rapid declines in viral RNA levels. Because HCV can rapidly develop resistance to NS5A inhibitors used alone, Daclatasvir is combined with an agent from a different class (typically the NS5B polymerase inhibitor sofosbuvir) to achieve sustained virologic response and minimize resistance.

Daclavir tablets are taken orally, once daily, with or without food, swallowed whole with water. Do not crush or chew the tablet unless advised by a physician.

Daclavir is primarily metabolized by the CYP3A4 enzyme, making it susceptible to clinically significant drug interactions.

• Strong CYP3A4 inducers (rifampin, phenytoin, carbamazepine, St. John's Wort): significantly lower Daclavir plasma levels, risking loss of antiviral efficacy and treatment failure. Concurrent use is contraindicated.
• Strong CYP3A4 inhibitors (ketoconazole, clarithromycin, ritonavir-boosted protease inhibitors): increase Daclavir exposure; the dose should be reduced to 30 mg daily.
• Moderate CYP3A4 inducers (e.g., efavirenz): reduce Daclavir levels; the dose should be increased to 90 mg daily.
• Amiodarone (when Daclavir is used with sofosbuvir): risk of serious, symptomatic bradycardia and cardiac arrest (see Precautions and Warnings). This combination should be avoided.
• P-glycoprotein and OATP1B1 substrates (e.g., digoxin, rosuvastatin): Daclavir may increase plasma concentrations of these drugs; monitoring is advised.

Adverse effects of Daclavir are generally reported for the combination regimen rather than Daclavir alone.

• Common (with sofosbuvir): headache, fatigue.
• Common (with sofosbuvir + ribavirin): headache, fatigue, anemia, nausea.
• Less common: diarrhea, insomnia, irritability, arthralgia, rash, pruritus.
• Serious (rare but important): serious symptomatic bradycardia (particularly with concurrent amiodarone and sofosbuvir - see Contraindications); hepatitis B virus reactivation in HCV/HBV coinfected patients (see Precautions and Warnings).

There are no adequate and well-controlled studies of Daclavir in pregnant women. Animal reproduction studies did not show harm at clinically relevant doses, but human data are lacking. Daclavir should be used during pregnancy only if clearly needed and the potential benefit justifies the potential risk to the fetus; consult a physician before use. If Daclavir is used as part of a ribavirin-containing regimen, ribavirin's strict pregnancy contraindication and pregnancy-avoidance requirements (for both female patients and female partners of male patients) apply. It is not known whether Daclavir passes into human breast milk; a decision should be made to discontinue breastfeeding or discontinue the drug, taking into account the importance of treatment to the mother, under medical supervision.

Hepatitis B virus (HBV) reactivation: Cases of HBV reactivation, some fatal, have been reported in patients coinfected with HCV and HBV who received direct-acting antivirals including Daclavir-based regimens. All patients should be screened for HBV infection before starting Daclavir therapy, and coinfected patients should be monitored during and after treatment.

Cardiac risk with amiodarone: Serious symptomatic bradycardia, including some fatal cases, has occurred when Daclavir was co-administered with sofosbuvir and amiodarone. This combination should be avoided; if no alternative exists, cardiac monitoring is required (see Contraindications).

Monotherapy risk: Daclavir should never be used alone for HCV treatment, as this promotes rapid development of viral resistance.

Hepatic impairment: No dose adjustment of Daclavir is required for mild, moderate, or severe hepatic impairment, but overall regimen selection (e.g., ribavirin use) should be guided by a specialist in patients with decompensated cirrhosis.

Renal impairment: No dose adjustment of Daclavir is needed based on renal function.

There is limited clinical experience with Daclavir overdose. In the event of a suspected overdose, seek immediate medical attention or contact a poison control center. Management should include general supportive measures, monitoring of vital signs and cardiac status, and observation for adverse reactions. There is no specific antidote for Daclavir overdose; hemodialysis is unlikely to significantly remove the drug due to its high protein binding.

Store at room temperature (below 30°C), away from light and moisture. Keep out of reach of children.

Renal impairment: No dose adjustment of Daclavir is required in patients with any degree of renal impairment, including those on dialysis.

Hepatic impairment: No dose adjustment of Daclavir is required in mild, moderate, or severe hepatic impairment; use in decompensated cirrhosis should be guided by a specialist, generally with ribavirin added to the regimen.

Elderly: No dose adjustment of Daclavir is required based on age alone, though overall health status and concomitant medications should be considered.

HIV/HCV coinfection: Daclavir can be used with careful attention to interactions with antiretroviral drugs (some HIV protease inhibitors and non-nucleoside reverse transcriptase inhibitors require dose adjustment of Daclavir).

The standard duration of Daclavir-based therapy is 12 weeks, though some regimens (e.g., in decompensated cirrhosis or treatment-experienced patients) may extend to 24 weeks per specialist guidance. The full course of Daclavir must be completed as prescribed, even if the patient feels well, to achieve sustained virologic response and prevent relapse or resistance.

Daclatasvir belongs to the class of Direct-Acting Antivirals (DAAs), specifically the hepatitis C virus NS5A inhibitors.

Daclatasvir binds to the N-terminus of the hepatitis C virus NS5A protein, inhibiting both viral RNA replication and virion assembly. This dual mechanism disrupts the HCV replication complex, leading to a rapid and profound decline in circulating viral RNA when Daclatasvir is combined with an agent of a different mechanistic class, such as the NS5B polymerase inhibitor sofosbuvir.

The safety and effectiveness of Daclavir in pediatric patients younger than 18 years have not been established. Daclavir should not be used in children unless specifically directed by a pediatric specialist as part of a clinical protocol.