Abacavir/lamivudine

Administration

• Type: Antiviral
• Dosage Forms: TAB 600mg, 300mg
• Routes of Administration: Oral
• Common Trade Names: Epzicom, APO, Auro, Kivexa, MYLAN, PMS, TEVA
• Administered W/WO food.

Adult Dosing

HIV infection

• 1 tab PO daily (abacavir 600 mg and lamivudine 300 mg)

Pediatric Dosing

HIV infection

• >25kg: 1 tab PO daily

Special Populations

Pregnancy Rating

• Abacavir: Benefits outweigh risks during pregnancy
• Lamivudine: Benefits outweigh risks during pregnancy

Lactation risk

• Avoid breastfeeding

Renal Dosing

• Adult:
  • CrCl <50: Avoid use
• Pediatric:
  • CrCl <50: Avoid use

Hepatic Dosing

• Adult:
  • Child-Pugh Class A: Avoid use
  • Child-Pugh Class B or C: Contraindicated
• Pediatric:
  • Child-Pugh Class A: Avoid use
  • Child-Pugh Class B or C: Contraindicated

Contraindications

• Allergy to class/drug
• HLA-B*5701 Positive pts
• Hepatic impairment

Adverse Reactions

Serious

• Hypersensitivity reaction
• Anaphylaxis
• Stevens-Johnson syndrome
• Toxic epidermal necrolysis
• Erythema multiforme
• MI
• Lactic acidosis
• Hepatomegaly w/ steatosis
• Pancreatitis
• HBV exacerbation, post-treatment
• Peripheral neuropathy
• Anemia, severe
• Rhabdomyolysis
• Immune reconstitution syndrome
• Autoimmune disorders

Common

• Insomnia, depression, fatigue, abnormal dreams
• Headache, dizziness
• Nausea, diarrhea, abdominal pain,
• Rash
• Fever
• Anxiety
• Hyperamylasemia

Disease-related concerns

• Coronary heart disease: Use associated with increased risk of MI in some cohort studies (Elion 2018; HHS 2017)
• Chronic hepatitis B: Severe acute exacerbations of hepatitis B have been reported in patients who are co-infected with hepatitis B virus (HBV) and HIV-1 and have discontinued lamivudine, which is one component of abacavir/lamivudine.

Pharmacology

• Half-life:
  • Abacavir: 1.5h
  • Lamivudine: 5-7h
• Metabolism:
  • Abacavir: Liver
  • Lamivudine: Intracellular; active metabolite
• Excretion:
  • Abacavir: Urine 82.2% (1.2% unchanged), feces 16%
  • Lamivudine: Urine (primarily unchanged)

Mechanism of Action

Both drugs inhibit reverse transcriptase and incorporates into viral DNA, resulting in chain termination

See Also

• Elion RA, Althoff KN, Zhang J, et al; American AIDS Cohort Collaboration on Research and Design of IeDEA. Recent abacavir use increases risk of type 1 and type 2 myocardial infarctions among adults with HIV. J Acquir Immune Defic Syndr. 2018;78(1):62-72. doi: 10.1097/QAI.0000000000001642. [PubMed 29419568]
• Epzicom (abacavir and lamivudine) [prescribing information]. Research Triangle Park, NC: GlaxoSmithKline; April 2018.
• HHS Panel on Antiretroviral Guidelines for Adults and Adolescents. Guidelines for the use of antiretroviral agents in HIV-1-infected adults and adolescents. http://www.aidsinfo.nih.gov/ContentFiles/AdultandAdolescentGL.pdf. Updated October 17, 2017. Accessed October 18, 2017.
• Kivexa (abacavir and lamivudine) [product monograph]. Laval, Quebec, Canada: ViiV Healthcare ULC; December 2018.