Resof 400mg

Drug profile

Resof is comes under the pharmacological category of hepatitis C virus NS5B viral RNA polymerase inhibitor

Resof tablets are prescription medicine, single dose therapy not used ordinarily it is used for the patients who are all having a valid prescription and under the guidance of medical practitioner

In most of the patients, Resof is not combined with peg interferon because of adverse effects produced by peg interferon. Even though this concomitant is avoided, the curable standard of Resof tablet is outstanding rate.

Trade name: Resof

Active ingredient: Sofosbuvir

Strength: 400MG

Mfg: Dr.Reddy’s

Package: 28 tablets in a container

Category: Anti-hepaciviral activity

Prescribing information of Resof

The prescribing information of Resof tablets for the patients affected with chronic hepatitis C infection;

The effective of Resof is established in the genotype I, II III or IV infections, patients who are having HIV-1/HBV co infection.

Resof mainly prescribed for adolescent patients, and for pediatric patients with age of 12 years or weighing at least 35kg in genotype II or III induced hepatitis C infection

Resof is majorly indicated for hepatitis C viral infection therapy by combining with other anti-viral medicines

Mechanism of Resof

Resof containing sofosbuvir is a pan genotype, HCV NS5B RNA polymerase inhibitor.

This RNA polymerase enzyme is involved in viral production. Resof is a prodrug which converted into active pharmacological metabolite by undergoing intracellular metabolism.

The active metabolite is known as uridine triphosphate. This metabolite is get inserted into viral RNA by HCV viral RNA polymerase and exhibits anti-viral activity by chain termination process

Absorption

After an oral administration, the peak plasma time of Resof is reaches within 0.5 to 2 hours and its circulating metabolite GS-331007 has peak plasma time 2 to 4 hours

Distribution

The human plasma protein bound capacity with Resof is occur nearly at the range of 61 to 65%

The circulating metabolite has minimal protein bounding property.

Metabolism

Resof is highly metabolized in liver, whereas Resof is a substrate of P-gp & BCRP

Excretion

Resof is eliminated through urine by glomerular filteration

The terminal half life period of Resof is 0.51 hours and its metabolite has 27 hours

How to take the Tablet Resof

Generally Resof is administered with or without food.

Resof tablet is taken as a single dose

Do not crush or chew the tablet, swallow the tablet as whole with some water

Dosage regimens

400mg of Resof (sofosbuvir)

The recommended dosage of Resof by combination with other medicines;

Patient acquired with genotype I, IV, V or VI chronic hepatitis C viral infection:

Resof is combined with ribavirin and peg interferon alfa should be taken as a single dose for 12 weeks

Resof and ribavirin should be taken in case of patients are undesirable to take peg interferon alfa for 24 weeks

Patients suffered with genotype II chronic hepatitis C:

Resof should be combined with ribavirin as a single dose for 12 weeks

Patients with genotype III hepatitis:

Resof combined with ribavirin and peg interferon alfa and it should be taken as a single dose for 12 weeks

Otherwise Resof with ribavirin should be taken as single dose for 24 weeks

In liver transplantation:

Resof should be concurrently used with ribavirin as a single dose until liver transmission.

In pediatric:

Resof tablet is recommended for the children at age 12 or weight of at least 35kg;

In without cirrhosis or with child Pugh A or compensated:

The recommended dosage is one tablet of Resof should be combined with weight based ribavirin as a single dose for 12 weeks

In decompensated cirrhosis:

The prescribed dosage of Resof is one tablet should be used with ribavirin for 24 weeks

Ribavirin dosage:

Ribavirin is recommended to take in two divided doses only with food

Initial dose 600mg slowly increased up to 100mg per day in weight less than 75kg

1200mg should be taken per day with the weight at least 75kg

In pediatric ribavirin dosage;

<47kg: 15mg/kg/day

47 to 49kg: 600mg/day

50 to 65kg: 800mg/day

66 to 80kg: 1000mg/day

>80kg: 1200mg/day

No dosage adjustment is followed in the therapy using Resof in case of renal and hepatic impairment.

Resof caused side effects

General side effects of Resof;

Neutropenia

Anemia

Loss of appetite

Rash

Myalgia

HBV reactivation

Pruritus

Depression

Asthenia

Irritability

Bradycardia

Diarrhea

Fever, chills

Influenza like syndrome

Pancytopenia

Fatigue

Headache

Insomnia

Nausea

Drug interactions

Resof with anticonvulsants like phenytoin, Phenobarbital or carbamazepine causes decreasing the effect of Resof

Resof with analeptic drug like modafinil causes decreasing the effect of concentration of Resof.

Resof is a substrate of P-gp & BCRP transporters. While using Resof with P-gp or BCRP strong inducers like rifampin or st Johns wort may causes decreasing the plasma concentration of sofosbuvir. Thus the results depletion of therapeutic effect of Resof

While combining with Resof with amiodarone, no effect of concentration occurs but symptomatic bradycardia occurs

Resof with anti-mycobacterials causes depletion in effect of concentration of Resof

Resof co administration with P-gp or BCRP inhibitors, causes increasing the plasma concentration of Resof

Resof with vitamin K antagonist, fluctuate the effect of vitamin K antagonist

Food drug interaction

Diet should be followed under the guidance of physician

Drug with herbal interaction occurs like; Resof with st Johns wort may cause depletion of therapeutic effect of Resof

No food drug interaction occurs while taking Resof, but caution should be taken during therapy

Possible contraindications

Resof tablet combined with ribavirin or peg interferon alfa, contraindicated to pregnancy condition

Hypersensitive reaction produce because of patients contraindicated to the component present in Resof tablet

Safety measures

Resof combined with P-gp or BCRP strong inducers leading to loss of therapeutic effect. Avoid this combination.

While concomitant amiodarone with Resof, patient must counsel about the exposure of this combination, on the other hand some alternative medicines should be prescribed to reduce the risk of symptomatic bradycardia

Use with caution in decompensated condition; ribavirin should be combined with Resof. Ribavirin causes fetal abnormalities and death. In pregnancy condition ribavirin not recommended

In HIV-1/HBV co infected patients, HBV reactivation occurs during or after the treatment, to avoid this problem patient must examine to calculate the level of HBV surface antigen & HBV core antibody before starting the treatment

Pregnancy and lactation

Resof comes under pregnancy category B1

Whereas Resof combined with ribavirin in chronic condition, ribavirin has pregnancy category X; which means causes fetal damage even to death

Ribavirin should not be recommended in pregnancy

Breast feeding should not be recommended

Storage and handling

The storage condition of Resof tablets;

Resof tablet container stored at room temperature below 30^oC

Container should be kept in dry and cool place, free from moisture, heat & light

Keep out of reach from children

The shelf life of the tablet is around 5 years

Missed dose

Resof is a prescription medicine, if patient fail to take the dose of Resof must consult with physician and take the dose within the time

Otherwise the missed dose should be skipped and follow the regular dosing schedule

Medicine schedule: prescription medicine

Over dosage

The maximum dose of sofosbuvir is 1200mg, there is no distinct antidote is required for over dose of Resof.

If overdose occurs in the patients two possible way to overcome from this difficulty;

Patients first confirmed from the toxicity and Patients should be periodically monitored for their symptoms & clinical status. To maintain safety measures properly

Hemodialysis is another method which is involved in over dosage condition; predominantly eliminate the sofosbuvir circulating metabolite contents from the body with separating at the range of 54%