Drug Detail:Abacavir and lamivudine (Abacavir and lamivudine [ a-bak-a-veer-and-la-miv-yoo-deen ])
Drug Class: Antiviral combinations
Usual Adult Dose for HIV Infection
1 tablet orally once a day
Use: In combination with other antiretroviral agents, for the treatment of HIV-1 infection
Usual Adult Dose for Occupational Exposure
US Public Health Service Working Group Recommendations: 1 tablet orally once a day
Duration of therapy: 28 days, if tolerated
Comments:
- Only with expert consultation, as part of an alternative antiretroviral regimen for use as HIV postexposure prophylaxis
- Prophylaxis should be started as soon as possible, preferably within hours after exposure.
- The optimal duration of prophylaxis is unknown and may differ based on institution protocol.
- Current guidelines should be consulted for additional information.
Usual Pediatric Dose for HIV Infection
At least 25 kg: 1 tablet orally once a day
Comments:
- Use of the individual components is recommended for patients less than 25 kg; the manufacturer product information for abacavir and lamivudine should be consulted.
- Before prescribing this drug, the ability to swallow tablets should be assessed.
Use: In combination with other antiretroviral agents, for the treatment of HIV-1 infection
Renal Dose Adjustments
CrCl less than 30 mL/min: Not recommended.
Comments:
- Patients with sustained CrCl between 30 and 49 mL/min should be monitored for hematologic toxicities.
- If lamivudine dose adjustment is indicated (e.g., patient develops new/worsening neutropenia or anemia), this drug should be discontinued and the individual components should be used.
Liver Dose Adjustments
Mild liver dysfunction (Child-Pugh A): Not recommended.
Moderate or severe liver dysfunction (Child-Pugh B or C): Contraindicated
Comments:
- If abacavir dose adjustment is needed for patients with mild liver dysfunction, the individual components should be used.
Precautions
US BOXED WARNINGS:
- HYPERSENSITIVITY REACTIONS: Serious and sometimes fatal hypersensitivity reactions (with multiple organ involvement) reported with abacavir. Patients with the human leukocyte antigen subtype B*5701 (HLA-B*5701) allele are at higher risk of abacavir hypersensitivity reactions; however, such reactions have occurred in patients without the HLA-B*5701 allele. This drug is contraindicated in patients with prior hypersensitivity reaction to abacavir and in HLA-B*5701-positive patients. All patients should be screened for the HLA-B*5701 allele before starting or restarting treatment with this drug (unless HLA-B*5701 allele assessment previously documented). Regardless of HLA-B*5701 status, this drug should be discontinued without delay if hypersensitivity reaction is suspected, even if other diagnoses are possible. After hypersensitivity reaction to this drug, NEVER restart this or any other abacavir-containing product as more severe symptoms (including death) can occur within hours. Similar severe reactions also reported after restarting abacavir-containing products in patients with no history of abacavir hypersensitivity.
- EXACERBATIONS OF HEPATITIS B: Severe acute exacerbations of hepatitis B reported in patients coinfected with HBV and HIV-1 after stopping lamivudine. Hepatic function of coinfected patients should be closely monitored with clinical and laboratory follow-up for at least several months after stopping this drug. If appropriate, initiation/resumption of antihepatitis B therapy may be necessary.
CONTRAINDICATIONS:
- Presence of the HLA-B*5701 allele
- Prior hypersensitivity reaction to either active component
- Moderate or severe liver dysfunction
Safety and efficacy have not been established in pediatric patients weighing less than 25 kg.
Consult WARNINGS section for additional precautions.
Dialysis
Data not available
Other Comments
Administration advice:
- Before starting this drug, screen for the HLA-B*5701 allele.
- Before starting this drug, review medical history for prior exposure to any abacavir-containing product.
- Use in combination with other antiretroviral agents.
- Administer with or without food.
- Consult the manufacturer product information regarding missed doses.
General:
- Each combination tablet contains abacavir 600 mg and lamivudine 300 mg.
Monitoring:
- Hematologic: For hematologic toxicities in patients with sustained CrCl between 30 and 49 mL/min (during therapy)
- Hepatic: Hepatic function of HBV/HIV-1-coinfected patients with clinical and laboratory follow-up (for at least several months after stopping this drug)
Patient advice:
- Read the US FDA-approved patient labeling (Medication Guide); read the Medication Guide and Warning Card (dispensed with each new and refill prescription) every time; carry the Warning Card with you.
- Contact health care provider immediately if signs/symptoms of hypersensitivity develop; do not restart this or any other abacavir-containing product after a hypersensitivity reaction (dispose of unused product).
- If this drug is stopped for any reason besides hypersensitivity, do not restart it (or any other abacavir-containing product) without consulting physician; medical care must be readily accessible.
- Stop this drug if clinical symptoms suggestive of lactic acidosis or pronounced hepatotoxicity develop.
- Notify health care provider at once of any signs/symptoms of infection.
- Notify health care provider if any unusual symptom develops or if any known symptom persists/worsens.