Abacavir

Generic Name: abacavir

Over-the-Counter (OTC)

Brand Names:

Abacavir

11 DESCRIPTION Abacavir sulfate, USP is a synthetic carbocyclic nucleoside analogue with inhibitory activity against HIV-1. The chemical name of abacavir sulfate, USP is (1S,4R)-4-[2-amino-6-(cyclopropylamino)-9H-purin-9-yl]-2-cyclopentene-1-methanol sulfate (salt) (2:1). Abacavir sulfate, USP is the enantiomer with 1S, 4R absolute configuration on the cyclopentene ring. It has a molecular formula of (C14H18N6O)2•H2SO4 and a molecular weight of 670.74 daltons.

Overview

11 DESCRIPTION Abacavir sulfate, USP is a synthetic carbocyclic nucleoside analogue with inhibitory activity against HIV-1. The chemical name of abacavir sulfate, USP is (1S,4R)-4-[2-amino-6-(cyclopropylamino)-9H-purin-9-yl]-2-cyclopentene-1-methanol sulfate (salt) (2:1). Abacavir sulfate, USP is the enantiomer with 1S, 4R absolute configuration on the cyclopentene ring. It has a molecular formula of (C14H18N6O)2•H2SO4 and a molecular weight of 670.74 daltons.

Uses

1 INDICATIONS AND USAGE Abacavir tablets, in combination with other antiretroviral agents, are indicated for the treatment of human immunodeficiency virus (HIV-1) infection. Abacavir, a nucleoside analogue human immunodeficiency virus (HIV-1) reverse transcriptase inhibitor, is indicated in combination with other antiretroviral agents for the treatment of HIV-1 infection. ( 1 )

Dosage

2 DOSAGE AND ADMINISTRATION • Before initiating abacavir tablets, screen for the HLA-B*5701 allele. ( 2.1 ) • Adults: 600 mg daily, administered as either 300 mg twice daily or 600 mg once daily. ( 2.2 ) • Pediatric Patients Aged 3 Months and Older: Administered either once or twice daily. Dose should be calculated on body weight (kg) and should not exceed 600 mg daily. ( 2.3 ) • Patients with Hepatic Impairment: Mild hepatic impairment – 200 mg twice daily. ( 2.4 ) 2.1 Screening for HLA-B*5701 Allele Prior to Starting Abacavir Tablets Screen for the HLA-B*5701 allele prior to initiating therapy with abacavir tablets [see Boxed Warning, Warnings and Precautions ( 5.1 )].

Side Effects

6 ADVERSE REACTIONS The following adverse reactions are discussed in other sections of the labeling: • Serious and sometimes fatal hypersensitivity reactions [see Boxed Warning, Warnings and Precautions ( 5.1 )]. • Lactic acidosis and severe hepatomegaly with steatosis [see Warnings and Precautions ( 5.2 )]. • Immune reconstitution syndrome [see Warnings and Precautions ( 5.3 )]. • Myocardial infarction [see Warnings and Precautions ( 5.4 )]. • The most commonly reported adverse reactions of at least moderate intensity (incidence greater than or equal to 10%) in adult HIV-1 clinical trials were nausea, headache, malaise and fatigue, nausea and vomiting, and dreams/sleep disorders.

Interactions

7 DRUG INTERACTIONS • Methadone: An increased methadone dose may be required in a small number of patients. ( 7.1 ) • Riociguat: The riociguat dose may need to be reduced. ( 7.2 ) 7. 1 Methadone In a trial of 11 HIV-1-infected subjects receiving methadone-maintenance therapy with 600 mg of abacavir twice daily (twice the currently recommended dose), oral methadone clearance increased [see Clinical Pharmacology ( 12.3 )]. This alteration will not result in a methadone dose modification in the majority of patients; however, an increased methadone dose may be required in a small number of patients.

Warnings

WARNING: RISK OF HYPERSENSITIVITY REACTIONS, LACTIC ACIDOSIS, AND SEVERE HEPATOMEGALY WARNING: HYPERSENSITIVITY REACTIONS Serious and sometimes fatal hypersensitivity reactions, with multiple organ involvement, have occured with abacavir tablets. Patients who carry the HLA-B*5701 allele are at a higher risk of a hypersensitivity reaction to abacavir; although, hypersensitivity reactions have occurred in patients who do not carry the HLA-B*5701 allele [see Warnings and Precautions ( 5.1 )]. 5 WARNINGS AND PRECAUTIONS • Lactic acidosis and severe hepatomegaly with steatosis, including fatal cases, have been reported with the use of nucleoside analogues. ( 5.2 ) • Immune reconstitution syndrome has been reported in patients treated with combination antiretroviral therapy. ( 5.3 ) 5.1 Hypersensitivity Reactions Serious and sometimes fatal hypersensitivity reactions have occurred with abacavir. These hypersensitivity reactions have included multi-organ failure and anaphylaxis and typically occurred within the first 6 weeks of treatment with abacavir (median time to onset was 9 days); although abacavir hypersensitivity reactions have occurred any time during treatment [see Adverse Reactions ( 6.1 )]. 4 CONTRAINDICATIONS • Presence of HLA-B*5701 allele. ( 4 ) • Prior hypersensitivity reaction to abacavir. ( 4 ) • Moderate or severe hepatic impairment. ( 4 )

Pregnancy

8.1 Pregnancy Pregnancy Exposure Registry There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to abacavir during pregnancy. Healthcare Providers are encouraged to register patients by calling the Antiretroviral Pregnancy Registry (APR) at 1-800-258-4263. Risk Summary Available data from the APR show no difference in the overall risk of birth defects for abacavir compared with the background rate for birth defects of 2.7% in the Metropolitan Atlanta Congenital Defects Program (MACDP) reference population (see Data). The APR uses the MACDP as the U.S.

Storage

16 HOW SUPPLIED/STORAGE AND HANDLING Abacavir tablets, USP containing abacavir sulfate, USP equivalent to 300 mg abacavir are yellow colored, biconvex, capsule shaped, film coated tablets debossed with 'H' on one side and '139' on other side separating 13 & 9 with score line.

Frequently Asked Questions

What is Abacavir used for?

1 INDICATIONS AND USAGE Abacavir tablets, in combination with other antiretroviral agents, are indicated for the treatment of human immunodeficiency virus (HIV-1) infection. Abacavir, a nucleoside analogue human immunodeficiency virus (HIV-1) reverse transcriptase inhibitor, is indicated in combination with other antiretroviral agents for the treatment of HIV-1 infection. ( 1 )

What are the side effects of Abacavir?

6 ADVERSE REACTIONS The following adverse reactions are discussed in other sections of the labeling: • Serious and sometimes fatal hypersensitivity reactions [see Boxed Warning, Warnings and Precautions ( 5.1 )]. • Lactic acidosis and severe hepatomegaly with steatosis [see Warnings and Precautions ( 5.2 )]. • Immune reconstitution syndrome [see Warnings and Precautions ( 5.3 )]. • Myocardial infarction [see Warnings and Precautions ( 5.4 )]. • The most commonly reported adverse reactions of at least moderate intensity (incidence greater than or equal to 10%) in adult HIV-1 clinical trials were nausea, headache, malaise and fatigue, nausea and vomiting, and dreams/sleep disorders.

Can I take Abacavir during pregnancy?

8.1 Pregnancy Pregnancy Exposure Registry There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to abacavir during pregnancy. Healthcare Providers are encouraged to register patients by calling the Antiretroviral Pregnancy Registry (APR) at 1-800-258-4263. Risk Summary Available data from the APR show no difference in the overall risk of birth defects for abacavir compared with the background rate for birth defects of 2.7% in the Metropolitan Atlanta Congenital Defects Program (MACDP) reference population (see Data). The APR uses the MACDP as the U.S.

What are the important warnings for Abacavir?

WARNING: RISK OF HYPERSENSITIVITY REACTIONS, LACTIC ACIDOSIS, AND SEVERE HEPATOMEGALY WARNING: HYPERSENSITIVITY REACTIONS Serious and sometimes fatal hypersensitivity reactions, with multiple organ involvement, have occured with abacavir tablets. Patients who carry the HLA-B*5701 allele are at a higher risk of a hypersensitivity reaction to abacavir; although, hypersensitivity reactions have occurred in patients who do not carry the HLA-B*5701 allele [see Warnings and Precautions ( 5.1 )]. 5 WARNINGS AND PRECAUTIONS • Lactic acidosis and severe hepatomegaly with steatosis, including fatal cases, have been reported with the use of nucleoside analogues. ( 5.2 ) • Immune reconstitution syndrome has been reported in patients treated with combination antiretroviral therapy. ( 5.3 ) 5.1 Hypersensitivity Reactions Serious and sometimes fatal hypersensitivity reactions have occurred with abacavir. These hypersensitivity reactions have included multi-organ failure and anaphylaxis and typically occurred within the first 6 weeks of treatment with abacavir (median time to onset was 9 days); although abacavir hypersensitivity reactions have occurred any time during treatment [see Adverse Reactions ( 6.1 )]. 4 CONTRAINDICATIONS • Presence of HLA-B*5701 allele. ( 4 ) • Prior hypersensitivity reaction to abacavir. ( 4 ) • Moderate or severe hepatic impairment. ( 4 )

Related Medications

Medical Disclaimer

This drug information is for educational purposes only and should not replace professional medical advice. Drug information is sourced from the FDA National Drug Code Directory and Structured Product Labeling. Always consult with a healthcare provider before starting, stopping, or changing any medication.