VIRGAN EYE GEL 1.5mg/G

Product Information

Registration Status: Active

VIRGAN EYE GEL 1.5mg/G is approved to be sold in Singapore with effective from 2002-01-18. It is marketed by DCH AURIGA SINGAPORE, with the registration number of SIN11778P.

This product contains Ganciclovir 0.15g/ 100g in the form of OINTMENT. It is approved for OPHTHALMIC use.

This product is manufactured by FARMILA-THEA FARMACEUTICI S.P.A in ITALY.

It is a Prescription Only Medicine that can only be obtained from a doctor or a dentist, or a pharmacist with a prescription from a Singapore-registered doctor or dentist.

Ganciclovir

Description

An acyclovir analog that is a potent inhibitor of the Herpesvirus family including cytomegalovirus. Ganciclovir is used to treat complications from AIDS-associated cytomegalovirus infections. [PubChem]

Indication

For induction and maintenance in the treatment of cytomegalovirus (CMV) retinitis in immunocompromised patients, including patients with acquired immunodeficiency syndrome (AIDS). Also used in the treatment of severe cytomegalovirus (CMV) disease, including CMV pneumonia, CMV gastrointestinal disease, and disseminated CMV infections, in immunocompromised patients.

Mechanism of Action

Ganciclovir's antiviral activity inhibits virus replication. This inhibitory action is highly selective as the drug must be converted to the active form by a virus-encoded cellular enzyme, thymidine kinase (TK). TK catalyzes phosphorylation of ganciclovir to the monophosphate, which is then subsequently converted into the diphosphate by cellular guanylate kinase and into the triphosphate by a number of cellular enzymes. In vitro, ganciclovir triphosphate stops replication of herpes viral DNA. When used as a substrate for viral DNA polymerase, ganciclovir triphosphate competitively inhibits dATP leading to the formation of 'faulty' DNA. This is where ganciclovir triphosphate is incorporated into the DNA strand replacing many of the adenosine bases. This results in the prevention of DNA synthesis, as phosphodiester bridges can longer to be built, destabilizing the strand. Ganciclovir inhibits viral DNA polymerases more effectively than it does cellular polymerase, and chain elongation resumes when ganciclovir is removed.

Pharmacokinetics

Absorption
Poorly absorbed systemically following oral administration. Bioavailability under fasting conditions is approximately 5%, and when administered with food, 6 to 9% (about 30% with a fatty meal).
Distribution
* 0.74 ± 0.15 L/kg
Metabolism
Little to no metabolism, about 90% of plasma ganciclovir is eliminated unchanged in the urine.
Elimination

Clearance

* 128 +/- 63 mL/min [Patients with Renal Impairment (Clcr=50-79 mL/min)] * 57+/- 8 mL/min [Patients with Renal Impairment (Clcr=25-49 mL/min)] * 30 +/- 13 mL/min [Patients with Renal Impairment (Clcr<25 mL/min)] * 4.7+/- 2.2 mL/min/kg [pediatric patients, aged 9 months to 12 years]

Toxicity

Oral, mouse LD50: > 2g/kg. Intravenous, dog LD50: > 150mg/kg. Symptoms of overdose include irreversible pancytopenia, worsening GI symptoms, and acute renal failure. Suspected cancer agent.

Active Ingredient/Synonyms

2-(6-Amino-purin-9-ylmethoxy)-propane-1,3-diol | 2-amino-9-((1,3-Dihydroxypropan-2-yloxy)methyl)-1H-purin-6(9H)-one | 2-amino-9-((1,3-Dihydroxypropan-2-yloxy)methyl)-3H-purin-6(9H)-one | 2-amino-9-((1,3-Dihydroxypropan-2-yloxy)methyl)-9H-purin-6-ol | 2-Amino-9-(2-hydroxy-1-hydroxymethyl-ethoxymethyl)-1,9-dihydro-purin-6-one | 2-amino-9-(2-Hydroxy-1-hydroxymethylethoxymethyl)-6,9-dihydro-1H-6-purinone | 9-((2-Hydroxy-1-(hydroxymethyl)ethoxy)methyl)guanine | 9-[(1,3-dihydroxy-2-propoxy)methyl]guanine | GA2 | Ganciclovir | Ganciclovirum | Gancyclovir | Ganciclovir |


Source of information: Drugbank (External Link). Last updated on: 3rd July 18. *Trade Name used in the content below may not be the same as the HSA-registered product.

References

  1. Health Science Authority of Singapore - Reclassified POM
  2. Drugbank