MYRAN TABLET 2mg

Product Information

Registration Status: Active

MYRAN TABLET 2mg is approved to be sold in Singapore with effective from 1999-06-29. It is marketed by SHOEI UNIVERSAL CORPORATION PTE LTD, with the registration number of SIN11001P.

This product contains Busulfan 2mg in the form of TABLET. It is approved for ORAL use.

This product is manufactured by KOREA UNITED PHARMACEUTICAL INC in KOREA, and in REPUBLIC OF.

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.

Busulfan

Description

Busulfan is a bifunctional alkylating agent, having a selective immunosuppressive effect on bone marrow. It is not a structural analog of the nitrogen mustards. It has been used in the palliative treatment of chronic myeloid leukemia (myeloid leukemia, chronic), but although symptomatic relief is provided, no permanent remission is brought about. According to the Fourth Annual Report on Carcinogens (NTP 85-002, 1985), busulfan is listed as a known carcinogen. [PubChem]

Indication

For use in combination with cyclophosphamide as a conditioning regimen prior to allogeneic hematopoietic progenitor cell transplantation for chronic myelogenous (myeloid, myelocytic, granulocytic) leukemia (FDA has designated busulfan as an orphan drug for this use). It is also used as a component of pretransplant conditioning regimens in patients undergoing bone marrow transplantation for acute myeloid leukemia and nonmalignant diseases.

Mechanism of Action

Busulfan is an alkylating agent that contains 2 labile methanesulfonate groups attached to opposite ends of a 4-carbon alkyl chain. Once busulfan is hydrolyzed, the methanesulfonate groups are released and carbonium ions are produced. These carbonium ions alkylate DNA, which results in the interference of DNA replication and RNA transcription, ultimately leading to the disruption of nucleic acid function. Specifically, its mechanism of action through alkylation produces guanine-adenine intrastrand crosslinks. This occurs through an SN2 reaction in which the relatively nucleophilic guanine N7 attacks the carbon adjacent to the mesylate leaving group. This kind of damage cannot be repaired by cellular machinery and thus the cell undergoes apoptosis.

Pharmacokinetics

Absorption
Completely absorbed from the gastrointestinal tract. Busulfan is a small, highly lipophilic molecule that crosses the blood-brain-barrier. The absolute bioavailability, if a single 2 mg IV bolus injection is given to adult patients, is 80% ± 20%. In children (1.5 - 6 years old), the absolute bioavailability was 68% ± 31%. When a single oral dose is given to patients, the area under the curve (AUC) was 130 ng•hr/mL. The peak plasma concentration when given orally is 30 ng/mL (after dose normalization to 2 mg). It takes 0.9 hours to reach peak plasma concentration after dose normalization to 4 mg.
Distribution
Metabolism
Busulfan is extensively metabolizes in the hepatic. Busulfan is predominantly metabolized by conjugation with glutathione, both spontaneously and by glutathione S-transferase (GST) catalysis. GSTA1 is the primary GST isoform that facilitates the the metabolism of busulfan. Other GST isoforms that are also involved are GSTM1 and GSTP1. At least 12 metabolites have been identified among which tetrahydrothiophene, tetrahydrothiophene 12-oxide, sulfolane, and 3-hydroxysulfolane were identified. These metabolites do not have cytotoxic activity.
Elimination

Clearance

* 2.52 ml/min/kg [Following an infusion of dose of 0.8 mg/kg every six hours, for a total of 16 doses over four days]

Toxicity

Signs of overdose include allergic reaction, unusual bleeding or bruising, sudden weakness or unusual fatigue, persistent cough, congestion, or shortness of breath; flank, stomach or joint pain; pronounced nausea, vomiting, diarrhea, dizziness, confusion, or darkening of the skin, chills, fever, collapse, and loss of consciousness.

Active Ingredient/Synonyms

1,4-Bis(methanesulfonoxy)butane | 1,4-Butanediol dimethanesulfonate | 1,4-Dimesyloxybutane | 1,4-Dimethanesulfonoxybutane | Bisulfex | Busulfan | Busulfano | Busulfanum | Leucosulfan | Mablin | Mielucin | Misulban | Mitostan | Myeloleukon | Tetramethylene bis(methanesulfonate) | Busulfan |


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