ABACAVIR- abacavir sulfate tablet, film coated
For Healthcare Providers >

1. Abacavir Tablets Can Cause Serious Side Effects, Including:
2. Call Your Healthcare Provider Right Away If You Get Any Of The Following Symptoms That Could Be Signs Of Lactic Acidosis:
3. Call Your Healthcare Provider Right Away If You Have Any Of The Following Signs Of Liver Problems:
4. What Are Abacavir Tablets?
5. When Used With Other Antiretroviral Medicines To Treat Hiv-1 Infection, Abacavir Tablets May Help:
6. Do Not Take Abacavir Tablet If You:
7. Are Allergic To Abacavir Or Any Of The Ingredients In Abacavir Tablets. Before You Take Abacavir Tablets, Tell Your Healthcare Provider If You:
8. Tell Your Healthcare Provider If You Take:
9. How Should I Take Abacavir Tablets?
10. Abacavir Tablets Can Cause Serious Side Effects Including:
11. What Are The Ingredients In Abacavir Tablets?
12. Patient Information
13. Inform Patients:

Abacavir Tablets Can Cause Serious Side Effects, Including: ⮝

• Serious allergic reactions (hypersensitivity reaction)that can cause death have happened with abacavir tablets and other abacavir-containing products. Your risk of this allergic reaction is much higher if you have a gene variation called HLA-B*5701. Your healthcare provider can determine with a blood test if you have this gene variation.

If you get a symptom from 2 or more of the following groups while taking abacavir tablets, call your healthcare provider right away to find out if you should stop taking abacavir tablets.

	Symptom(s)
Group 1	Fever
Group 2	Rash
Group 3	Nausea, vomiting, diarrhea, abdominal (stomach area) pain
Group 4	Generally ill feeling, extreme tiredness, or achiness
Group 5	Shortness of breath, cough, sore throat

A list of these symptoms is on the Warning Card your pharmacist gives you.Carry this Warning Card with you at all times.

If you stop abacavir tablets because of an allergic reaction, never take abacavir or any other abacavir-containing medicine (EPZICOM, TRIUMEQ, or TRIZIVIR) again.

• If you have an allergic reaction, dispose of any unused abacavir tablets. Ask your pharmacist how to properly dispose of medicines.
• If you take abacavir tablets or any other abacavir-containing medicine again after you have had an allergic reaction,within hoursyou may getlife-threatening symptomsthat may includevery low blood pressure or death.
• If you stop abacavir tablets for any other reason, even for a few days, and you are not allergic to abacavir tablets, talk with your healthcare provider before taking them again. Taking abacavir tablets again can cause a serious allergic or life-threatening reaction, even if you never had an allergic reaction to them before.

If your healthcare provider tells you that you can take abacavir tablets again, start taking them when you are around medical help or people who can call a healthcare provider if you need one.

• Build-up of acid in your blood (lactic acidosis).Lactic acidosis can happen in some people who take abacavir tablets. Lactic acidosis is a serious medical emergency that can cause death.

Call Your Healthcare Provider Right Away If You Get Any Of The Following Symptoms That Could Be Signs Of Lactic Acidosis: ⮝

• feel very weak or tired
• unusual (not normal) muscle pain
• trouble breathing
• stomach pain with nausea and vomiting
• feel cold, especially in your arms and legs
• feel dizzy or light-headed
• have a fast or irregular heartbeat

Serious liver problemscan happen in people who take abacavir tablets. In some cases, these serious liver problems can lead to death. Your liver may become large (hepatomegaly) and you may develop fat in your liver (steatosis) when you take abacavir tablets.

Call Your Healthcare Provider Right Away If You Have Any Of The Following Signs Of Liver Problems: ⮝

• your skin or the white part of your eyes turns yellow (jaundice)
• dark or tea-colored urine
• light-colored stools (bowel movements)
• loss of appetite for several days or longer
• nausea
• pain, aching, or tenderness on the right side of your stomach area

You may be more likely to get lactic acidosis or serious liver problems if you are female, very overweight (obese), or have been taking nucleoside analogue medicines for a long time.

What Are Abacavir Tablets? ⮝

Abacavir tablets are a prescription HIV-1 (Human Immunodeficiency Virus type 1) medicine used with other antiretroviral medicines to treat HIV-1 infection. HIV-1 is the virus that causes Acquired Immune Deficiency Syndrome (AIDS).

The safety and effectiveness of abacavir tablets has not been established in children under 3 months of age.

When Used With Other Antiretroviral Medicines To Treat Hiv-1 Infection, Abacavir Tablets May Help: ⮝

• reduce the amount of HIV-1 in your blood. This is called viral load .
• increase the number of CD4+ (T) cells in your blood, that help fight off other infections.

Reducing the amount of HIV-1 and increasing the CD4+ (T) cells in your blood may help improve your immune system. This may reduce your risk of death or getting infections that can happen when your immune system is weak (opportunistic infections).

Abacavir tablets do not cure HIV-1 infection or AIDS.You must keep taking HIV-1 medicines to control HIV- 1 infection and decrease HIV-related illnesses.

Do Not Take Abacavir Tablet If You: ⮝

• have a certain type of gene variation called the HLA-B*5701 allele. Your healthcare provider will test you for this before prescribing treatment with abacavir tablets.

Are Allergic To Abacavir Or Any Of The Ingredients In Abacavir Tablets. Before You Take Abacavir Tablets, Tell Your Healthcare Provider If You: ⮝

• have been tested and know whether or not you have a particular gene variation called HLA-B*5701.
• have or have had liver problems, including hepatitis B or C virus infection.
• have heart problems, smoke, or have diseases that increase your risk of heart disease such as high blood pressure, high cholesterol, or diabetes.
• drink alcohol or take medicines that contain alcohol.
• are pregnant or plan to become pregnant. Talk to your healthcare provider if you are pregnant or plan to become pregnant.
  Pregnancy Registry.There is a pregnancy registry for women who take antiretroviral medicines during pregnancy. The purpose of this registry is to collect information about the health of you and your baby. Talk to your healthcare provider about how you can take part in this registry.
• are breastfeeding or plan to breastfeed.Do not breastfeed if you take abacavir tablets.
• You should not breastfeed if you have HIV-1 because of the risk of passing HIV-1 to your baby.

Tell your healthcare provider about all the medicines you take,including prescription and over-the-counter medicines, vitamins, and herbal supplements.
Some medicines interact with abacavir tablets.Keep a list of your medicines to show your healthcare provider and pharmacist.You can ask your healthcare provider or pharmacist for a list of medicines that interact with abacavir tablets.Do not start taking a new medicine without telling your healthcare provider.Your healthcare provider can tell you if it is safe to take abacavir tablets with other medicines.

Tell Your Healthcare Provider If You Take: ⮝

• any other medicine to treat HIV-1
• methadone

How Should I Take Abacavir Tablets? ⮝

• Take abacavir tablets exactly as your healthcare provider tells you.
• Do not change your dose or stop taking abacavir tablets without talking with your healthcare provider. If you miss a dose of abacavir tablets, take it as soon as you remember. Do not take 2 doses at the same time. If you are not sure about your dosing, call your healthcare provider.
• Stay under the care of a healthcare provider while taking abacavir tablets.
• Abacavir tablets may be taken with or without food.
• For children aged 3 months and older, your healthcare provider will prescribe a dose of abacavir tablets based on your child s body weight.
• Tell your healthcare provider if you or your child has trouble swallowing tablets. Abacavir comes as a tablet or as a liquid (oral solution).
• Do not run out of abacavir tablets. The virus in your blood may increase and the virus may become harder to treat. When your supply starts to run out, get more from your healthcare provider or pharmacy.
• If you take too much abacavir tablets, call your healthcare provider or go to the nearest hospital emergency room right away.

Abacavir Tablets Can Cause Serious Side Effects Including: ⮝

• Store abacavir tablets at room temperature, between 20 to 25 C (68 to 77 F).

Keep abacavir tablets and all medicines out of the reach of children.

General information for safe and effective use of abacavir tablets
Medicines are sometimes prescribed for purposes other than those listed in a Medication Guide. Do not use abacavir tablets for a condition for which it was not prescribed. Do not give abacavir tablets to other people, even if they have the same symptoms that you have. It may harm them.

If you would like more information, talk with your healthcare provider. You can ask your healthcare provider or pharmacist for the information about abacavir tablets that is written for health professionals.

For more information call Aurobindo Pharma USA, Inc. at 1-866-850-2876.

What Are The Ingredients In Abacavir Tablets? ⮝

Active ingredient: abacavir
Inactive ingredients: colloidal silicon dioxide, magnesium stearate, microcrystalline cellulose, and sodium starch glycolate. The tablets are coated with a film that is made of hypromellose, iron oxide yellow, polysorbate 80, titanium dioxide, and triacetin.

This Medication Guide has been approved by the U.S. Food and Drug Administration.

The brands listed are trademarks of their respective owners and are not trademarks of the Aurobindo Pharma Limited. The markers of these brands are not affiliated with and do not endorse the Aurobindo Pharma Limited or its products.

Distributed by:
American Health Packaging
Columbus, OH 43217

8202121/0817OS

Patient Information ⮝

Advise the patient to read the FDA-approved patient labeling (Medication Guide).

Hypersensitivity Reactions

Inform Patients: ⮝

• that a Medication Guide and Warning Card summarizing the symptoms of the abacavir hypersensitivity reaction and other product information will be dispensed by the pharmacist with each new prescription and refill of abacavir, and instruct the patient to read the Medication Guide and Warning Card every time to obtain any new information that may be present about abacavir. The complete text of the Medication Guide is reprinted at the end of this document.
• to carry the Warning Card with them.
• how to identify a hypersensitivity reaction[seeWarnings and Precautions (5.1),Medication Guide].
• that if they develop symptoms consistent with a hypersensitivity reaction they should call their healthcare provider right away to determine if they should stop taking abacavir.
• that a hypersensitivity reaction can worsen and lead to hospitalization or death if abacavir is not immediately discontinued.
• to not restart abacavir or any other abacavir-containing product following a hypersensitivity reaction because more severe symptoms can occur within hours and may include life-threatening hypotension and death.
• that if they have a hypersensitivity reaction, they should dispose of any unused abacavir to avoid restarting abacavir.
• that a hypersensitivity reaction is usually reversible if it is detected promptly and abacavir is stopped right away.
• that if they have interrupted abacavir for reasons other than symptoms of hypersensitivity (for example, those who have an interruption in drug supply), a serious or fatal hypersensitivity reaction may occur with reintroduction of abacavir.
• to not restart abacavir or any other abacavir-containing product without medical consultation and only if medical care can be readily accessed by the patient or others.

Lactic Acidosis/Hepatomegaly with Steatosis
Advise patients that lactic acidosis and severe hepatomegaly with steatosis have been reported with use of nucleoside analogues and other antiretrovirals. Advise patients to stop taking abacavir if they develop clinical symptoms suggestive of lactic acidosis or pronounced hepatotoxicity[seeBoxed Warning,Warnings and Precautions (5.2)].

Immune Reconstitution Syndrome
Advise patients to inform their healthcare provider immediately of any signs and symptoms of infection as inflammation from previous infection may occur soon after combination antiretroviral therapy, including when abacavir is started[seeWarnings and Precautions (5.3)].

Redistribution/Accumulation of Body Fat
Inform patients that redistribution or accumulation of body fat may occur in patients receiving antiretroviral therapy and that the cause and long-term health effects of these conditions are not known at this time[seeWarnings and Precautions (5.4)].

Pregnancy Registry
Advise patients that there is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to abacavir during pregnancy[seeUse in Specific Populations (8.1)].

Lactation
Instruct women with HIV-1 infection not to breastfeed because HIV-1 can be passed to the baby in the breast milk[seeUse in Specific Populations (8.2)].

Missed Dose
Instruct patients that if they miss a dose of abacavir, to take it as soon as they remember. Advise patients not to double their next dose or take more than the prescribed dose[seeDosage and Administration (2)].

Availability of Medication Guide
Instruct patients to read the Medication Guide before starting abacavir and to re-read it each time the prescription is renewed. Instruct patients to inform their physician or pharmacist if they develop any unusual symptom, or if any known symptom persists or worsens.

1. Highlights Of Prescribing Information
2. Hypersensitivity Reactions
3. Recent Major Changes
4. Indications And Usage
5. Dosage And Administration
6. Dosage Forms And Strengths
7. Contraindications
8. Warnings And Precautions
9. Adverse Reactions
10. Drug Interactions
11. Use In Specific Populations
12. Warning: Hypersensitivity Reactions, And Lactic Acidosis And Severe Hepatomegaly With Steatosis
13. 1 Indications And Usage
14. 2 Dosage And Administration
15. 3 Dosage Forms And Strengths
16. 4 Contraindications
17. 5 Warnings And Precautions
18. 6 Adverse Reactions
19. 7 Drug Interactions
20. 8 Use In Specific Populations
21. 10 Overdosage
22. 11 Description
23. 12 Clinical Pharmacology
24. 13 Nonclinical Toxicology
25. 14 Clinical Studies
26. 16 How Supplied/storage And Handling
27. Packaging Information
28. Package/label Display Panel Carton 300 Mg
29. Package/label Display Panel Blister 300 Mg

Highlights Of Prescribing Information ⮝

These highlights do not include all the information needed to use ABACAVIR TABLETS safely and effectively. See full prescribing information for ABACAVIR TABLETS.
ABACAVIR tablets, for oral use
Initial U.S. Approval: 1998

Hypersensitivity Reactions ⮝

• Serious and sometimes fatal hypersensitivity reactions have occurred with abacavir. ( 5.1)
• Hypersensitivity to abacavir is a multi-organ clinical syndrome. ( 5.1)
• Patients who carry the HLA-B *5701 allele are at a higher risk of experiencing a hypersensitivity reaction to abacavir. ( 5.1)
• Abacavir is contraindicated in patients with a prior hypersensitivity reaction to abacavir and in HLA-B*5701-positive patients. ( 4)
• Discontinue abacavir as soon as a hypersensitivity reaction is suspected. Regardless of HLA-B *5701 status, permanently discontinue abacavir if hypersensitivity cannot be ruled out, even when other diagnoses are possible. ( 5.1)
• Following a hypersensitivity reaction to abacavir, NEVER restart abacavir or any other abacavir-containing product. ( 5.1)

Lactic Acidosis and Severe Hepatomegaly with Steatosis

• Lactic acidosis and severe hepatomegaly with steatosis, including fatal cases, have been reported with the use of nucleoside analogues. ( 5.2)

Recent Major Changes ⮝

Warnings and Precautions, Related Products that are Not Recommended (5.6) Removed 03/2017

Indications And Usage ⮝

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

Dosage And Administration ⮝

• Before initiating abacavir, 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 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)

Dosage Forms And Strengths ⮝

Tablets: 300 mg scored (3)

Contraindications ⮝

• Presence of HLA-B*5701 allele. ( 4)
• Prior hypersensitivity reaction to abacavir. ( 4)
• Moderate or severe hepatic impairment. ( 4)

Warnings And Precautions ⮝

• Immune reconstitution syndrome and redistribution/accumulation of body fat have been reported in patients treated with combination antiretroviral therapy. ( 5.3, 5.4)

Adverse Reactions ⮝

• 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. (6.1)
• The most commonly reported adverse reactions of at least moderate intensity (incidence greater than or equal to 5%) in pediatric HIV-1 clinical trials were fever and/or chills, nausea and vomiting, skin rashes, and ear/nose/throat infections. (6.2)

To report SUSPECTED ADVERSE REACTIONS, contact Aurobindo Pharma USA, Inc. at 1-866-850-2876 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

Drug Interactions ⮝

• Methadone: An increased methadone dose may be required in a small number of patients. ( 7.1)

Use In Specific Populations ⮝

• Lactation: Women infected with HIV should be instructed not to breastfeed due to potential for HIV transmission. ( 8.2)

Additional pediatric use information for patients aged 3 months and above is approved for ViiV Healthcare Company s ZIAGEN (abacavir sulfate) tablets. However, due to ViiV Healthcare Company s marketing exclusivity rights, this drug product is not labeled with that pediatric information.

See 17 for PATIENT COUNSELING INFORMATION and Medication Guide.

Revised: 4/2017

Warning: Hypersensitivity Reactions, And Lactic Acidosis And Severe Hepatomegaly With Steatosis ⮝

Hypersensitivity Reactions
Serious and sometimes fatal hypersensitivity reactions, with multiple organ involvement, have occurred with abacavir.

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)].

Abacavir is contraindicated in patients with a prior hypersensitivity reaction to abacavir and in HLA-B*5701-positive patients [see Contraindications (4), Warnings and Precautions (5.1)] . All patients should be screened for the HLA-B*5701 allele prior to initiating therapy with abacavir or reinitiation of therapy with abacavir, unless patients have a previously documented HLA-B*5701 allele assessment. Discontinue abacavir immediately if a hypersensitivity reaction is suspected, regardless of HLA-B*5701 status and even when other diagnoses are possible [see Contraindications (4), Warnings and Precautions (5.1)].

Following a hypersensitivity reaction to abacavir, NEVER restart abacavir or any other abacavir-containing product because more severe symptoms, including death can occur within hours. Similar severe reactions have also occurred rarely following the reintroduction of abacavir-containing products in patients who have no history of abacavir hypersensitivity [see Warnings and Precautions (5.1)] .

Lactic Acidosis and Severe Hepatomegaly with Steatosis
Lactic acidosis and severe hepatomegaly with steatosis, including fatal cases, have been reported with the use of nucleoside analogues and other antiretrovirals. Discontinue abacavir if clinical or laboratory findings suggestive of lactic acidosis or pronounced hepatotoxicity occur [see Warnings and Precautions (5.2)] .

1 Indications And Usage ⮝

Abacavir tablets, in combination with other antiretroviral agents, are indicated for the treatment of human immunodeficiency virus (HIV-1) infection.

2 Dosage And Administration ⮝

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)] .

2.2 Recommended Dosage for Adult Patients

The recommended dosage of abacavir tablets for adults is 600 mg daily, administered orally as either 300 mg twice daily or 600 mg once daily, in combination with other antiretroviral agents.

2.3 Recommended Dosage for Pediatric Patients

Abacavir tablets are available as scored tablet for HIV-1-infected pediatric patients weighing greater than or equal to 14 kg for whom a solid dosage form is appropriate. Before prescribing abacavir tablets, children should be assessed for the ability to swallow tablets. If a child is unable to reliably swallow abacavir tablets, the oral solution formulation should be prescribed. The recommended oral dosage of abacavir tablets for HIV-1-infected pediatric patients is presented in Table 1.

Table 1. Dosing Recommendations for Abacavir Scored Tablets in Pediatric Patients

Weight (kg)	Twice-Daily Dosing Regimen
	AM Dose	PM Dose	Total Daily Dose
14 to <20	tablet (150 mg)	tablet (150 mg)	300 mg
> 20 to <25	tablet (150 mg)	1 tablet (300 mg)	450 mg
25	1 tablet (300 mg)	1 tablet (300 mg)	600 mg

Additional pediatric use information for patients aged 3 months and above is approved for ViiV Healthcare Company s ZIAGEN (abacavir sulfate) tablets. However, due to ViiV Healthcare Company s marketing exclusivity rights, this drug product is not labeled with that pediatric information.

2.4 Recommended Dosage for Patients with Hepatic Impairment

The recommended dose of abacavir tablets in patients with mild hepatic impairment (Child-Pugh Class A) is 200 mg twice daily. To enable dose reduction, abacavir oral solution (10 mL twice daily) should be used for the treatment of these patients. The safety, efficacy, and pharmacokinetic properties of abacavir have not been established in patients with moderate to severe hepatic impairment; therefore, abacavir tablets are contraindicated in these patients.

3 Dosage Forms And Strengths ⮝

Abacavir tablets, containing abacavir sulfate equivalent to 300 mg abacavir, are yellow colored, biconvex, capsule shaped, coated tablet, debossed with D and 88 on either side of the score line on one side and plain with a score line on other side.

4 Contraindications ⮝

Abacavir tablets are contraindicated in patients:

• who have the HLA-B*5701 allele [see Warnings and Precautions (5.1)] .
• with prior hypersensitivity reaction to abacavir [see Warnings and Precautions (5.1)] .
• with moderate or severe hepatic impairment [see Use in Specific Populations (8.6)] .

5 Warnings And Precautions ⮝

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)] . Patients who carry the HLA-B*5701 allele are at a higher risk of abacavir hypersensitivity reactions; although, patients who do not carry the HLA-B*5701 allele have developed hypersensitivity reactions. Hypersensitivity to abacavir was reported in approximately 206 (8%) of 2,670 patients in 9 clinical trials with abacavir-containing products where HLA-B*5701 screening was not performed. The incidence of suspected abacavir hypersensitivity reactions in clinical trials was 1% when subjects carrying the HLA-B*5701 allele were excluded. In any patient treated with abacavir, the clinical diagnosis of hypersensitivity reaction must remain the basis of clinical decision making.

Due to the potential for severe, serious, and possibly fatal hypersensitivity reactions with abacavir:

• All patients should be screened for the HLA-B*5701 allele prior to initiating therapy with abacavir or reinitiation of therapy with abacavir, unless patients have a previously documented HLA-B*5701 allele assessment.
• Abacavir is contraindicated in patients with a prior hypersensitivity reaction to abacavir and in HLA-B*5701-positive patients.
• Before starting abacavir, review medical history for prior exposure to any abacavir-containing product. NEVER restart abacavir or any other abacavir-containing product following a hypersensitivity reaction to abacavir, regardless of HLA-B*5701 status.
• To reduce the risk of a life-threatening hypersensitivity reaction, regardless of HLA-B*5701 status, discontinue abacavir immediately if a hypersensitivity reaction is suspected, even when other diagnoses are possible (e.g., acute onset respiratory diseases such as pneumonia, bronchitis, pharyngitis, or influenza; gastroenteritis; or reactions to other medications).
• If a hypersensitivity reaction cannot be ruled out, do not restart abacavir or any other abacavir-containing products because more severe symptoms which may include life-threatening hypotension and death, can occur within hours.
• If a hypersensitivity reaction is ruled out, patients may restart abacavir. Rarely, patients who have stopped abacavir for reasons other than symptoms of hypersensitivity have also experienced life-threatening reactions within hours of reinitiating abacavir therapy. Therefore, reintroduction of abacavir or any other abacavir-containing product is recommended only if medical care can be readily accessed.
• A Medication Guide and Warning Card that provide information about recognition of hypersensitivity reactions should be dispensed with each new prescription and refill.

5.2 Lactic Acidosis and Severe Hepatomegaly with Steatosis

Lactic acidosis and severe hepatomegaly with steatosis, including fatal cases, have been reported with the use of nucleoside analogues and other antiretrovirals. A majority of these cases have been in women. Obesity and prolonged nucleoside exposure may be risk factors. Caution should be exercised when administering abacavir to any patient with known risk factors for liver disease; however, cases have also been reported in patients with no known risk factors. Treatment with abacavir should be suspended in any patient who develops clinical or laboratory findings suggestive of lactic acidosis or pronounced hepatotoxicity (which may include hepatomegaly and steatosis even in the absence of marked transaminase elevations).

5.3 Immune Reconstitution Syndrome

Immune reconstitution syndrome has been reported in patients treated with combination antiretroviral therapy, including abacavir. During the initial phase of combination antiretroviral treatment, patients whose immune systems respond may develop an inflammatory response to indolent or residual opportunistic infections (such as Mycobacterium avium infection, cytomegalovirus, Pneumocystis jirovecii pneumonia [PCP], or tuberculosis), which may necessitate further evaluation and treatment.

Autoimmune disorders (such as Graves disease, polymyositis, and Guillain-Barr syndrome) have also been reported to occur in the setting of immune reconstitution; however, the time to onset is more variable and can occur many months after initiation of treatment.

5.4 Fat Redistribution

Redistribution/accumulation of body fat including central obesity, dorsocervical fat enlargement (buffalo hump), peripheral wasting, facial wasting, breast enlargement, and cushingoid appearance have been observed in patients receiving antiretroviral therapy. The mechanism and long-term consequences of these events are currently unknown. A causal relationship has not been established.

5.5 Myocardial Infarction

In a published prospective, observational, epidemiological trial designed to investigate the rate of myocardial infarction (MI) in patients on combination antiretroviral therapy, the use of abacavir within the previous 6 months was correlated with an increased risk of MI. In a sponsor-conducted pooled analysis of clinical trials, no excess risk of MI was observed in abacavir-treated subjects as compared with control subjects. In totality, the available data from the observational cohort and from clinical trials are inconclusive.

As a precaution, the underlying risk of coronary heart disease should be considered when prescribing antiretroviral therapies, including abacavir, and action taken to minimize all modifiable risk factors (e.g., hypertension, hyperlipidemia, diabetes mellitus, smoking).

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 Boxed Warning, Warnings and Precautions (5.2)] .
• Immune reconstitution syndrome [see Warnings and Precautions (5.3)] .
• Fat redistribution [see Warnings and Precautions (5.4)] .
• Myocardial infarction [see Warnings and Precautions (5.5)] .

6.1 Clinical Trials Experience in Adult Subjects

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared with rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice.

Serious and Fatal Abacavir-Associated Hypersensitivity Reactions
In clinical trials, serious and sometimes fatal hypersensitivity reactions have occurred with abacavir [see Boxed Warning, Warnings and Precautions (5.1)] . These reactions have been characterized by 2 or more of the following signs or symptoms: (1) fever; (2) rash; (3) gastrointestinal symptoms (including nausea, vomiting, diarrhea, or abdominal pain); (4) constitutional symptoms (including generalized malaise, fatigue, or achiness); (5) respiratory symptoms (including dyspnea, cough, or pharyngitis). Almost all abacavir hypersensitivity reactions include fever and/or rash as part of the syndrome.

Other signs and symptoms have included lethargy, headache, myalgia, edema, arthralgia, and paresthesia. Anaphylaxis, liver failure, renal failure, hypotension, adult respiratory distress syndrome, respiratory failure, myolysis, and death have occurred in association with these hypersensitivity reactions. Physical findings have included lymphadenopathy, mucous membrane lesions (conjunctivitis and mouth ulcerations), and maculopapular or urticarial rash (although some patients had other types of rashes and others did not have a rash). There were reports of erythema multiforme. Laboratory abnormalities included elevated liver chemistries, elevated creatine phosphokinase, elevated creatinine, and lymphopenia, and abnormal chest x-ray findings (predominantly infiltrates, which were localized).

Additional Adverse Reactions with Use of Abacavir
Therapy-Naive Adults: Treatment-emergent clinical adverse reactions (rated by the investigator as moderate or severe) with a greater than or equal to 5% frequency during therapy with abacavir 300 mg twice daily, lamivudine 150 mg twice daily, and efavirenz 600 mg daily compared with zidovudine 300 mg twice daily, lamivudine 150 mg twice daily, and efavirenz 600 mg daily from CNA30024 are listed in Table 2.

Table 2. Treatment-Emergent (All Causality) Adverse Reactions of at Least Moderate Intensity (Grades 2 to 4, Greater than or Equal to 5% Frequency) in Therapy-Naive Adults (CNA30024 *) through 48 Weeks of Treatment

* This trial used double-blind ascertainment of suspected hypersensitivity reactions. During the blinded portion of the trial, suspected hypersensitivity to abacavir was reported by investigators in 9% of 324 subjects in the abacavir group and 3% of 325 subjects in the zidovudine group. Ten (3%) cases of suspected drug hypersensitivity were reclassified as not being due to abacavir following unblinding.
Adverse Reaction	Abacavir plus Lamivudine plus Efavirenz (n = 324)	Zidovudine plus Lamivudine plus Efavirenz (n = 325)
Dreams/sleep disorders	10%	10%
Drug hypersensitivity	9%	<1%
Headaches/migraine	7%	11%
Nausea	7%	11%
Fatigue/malaise	7%	10%
Diarrhea	7%	6%
Rashes	6%	12%
Abdominal pain/gastritis/gastrointestinal signs and symptoms	6%	8%
Depressive disorders	6%	6%
Dizziness	6%	6%
Musculoskeletal pain	6%	5%
Bronchitis	4%	5%
Vomiting	2%	9%

Treatment-emergent clinical adverse reactions (rated by the investigator as moderate or severe) with a greater than or equal to 5% frequency during therapy with abacavir 300 mg twice daily, lamivudine 150 mg twice daily, and zidovudine 300 mg twice daily compared with indinavir 800 mg 3 times daily, lamivudine 150 mg twice daily, and zidovudine 300 mg twice daily from CNA3005 are listed in Table 3.

Table 3. Treatment-Emergent (All Causality) Adverse Reactions of at Least Moderate Intensity (Grades 2 to 4, Greater than or Equal to 5% Frequency) in Therapy-Naive Adults (CNA3005) through 48 Weeks of Treatment

Adverse Reaction	Abacavir plus Lamivudine/Zidovudine (n = 262)	Indinavir plus Lamivudine/Zidovudine (n = 264)
Nausea	19%	17%
Headache	13%	9%
Malaise and fatigue	12%	12%
Nausea and vomiting	10%	10%
Hypersensitivity reaction	8%	2%
Diarrhea	7%	5%
Fever and/or chills	6%	3%
Depressive disorders	6%	4%
Musculoskeletal pain	5%	7%
Skin rashes	5%	4%
Ear/nose/throat infections	5%	4%
Viral respiratory infections	5%	5%
Anxiety	5%	3%
Renal signs/symptoms	<1%	5%
Pain (non-site-specific)	<1%	5%

Five subjects receiving abacavir in CNA3005 experienced worsening of pre-existing depression compared with none in the indinavir arm. The background rates of pre-existing depression were similar in the 2 treatment arms.

Abacavir Once Daily versus Abacavir Twice Daily (CNA30021): Treatment-emergent clinical adverse reactions (rated by the investigator as at least moderate) with a greater than or equal to 5% frequency during therapy with abacavir 600 mg once daily or abacavir 300 mg twice daily, both in combination with lamivudine 300 mg once daily and efavirenz 600 mg once daily from CNA30021, were similar. For hypersensitivity reactions, subjects receiving abacavir once daily showed a rate of 9% in comparison with a rate of 7% for subjects receiving abacavir twice daily. However, subjects receiving abacavir 600 mg once daily experienced a significantly higher incidence of severe drug hypersensitivity reactions and severe diarrhea compared with subjects who received abacavir 300 mg twice daily. Five percent (5%) of subjects receiving abacavir 600 mg once daily had severe drug hypersensitivity reactions compared with 2% of subjects receiving abacavir 300 mg twice daily. Two percent (2%) of subjects receiving abacavir 600 mg once daily had severe diarrhea while none of the subjects receiving abacavir 300 mg twice daily had this event.

Laboratory Abnormalities: Laboratory abnormalities (Grades 3 to 4) in therapy-naive adults during therapy with abacavir 300 mg twice daily, lamivudine 150 mg twice daily, and efavirenz 600 mg daily compared with zidovudine 300 mg twice daily, lamivudine 150 mg twice daily, and efavirenz 600 mg daily from CNA30024 are listed in Table 4.

Table 4. Laboratory Abnormalities (Grades 3 to 4) in Therapy-Naive Adults (CNA30024) through 48 Weeks of Treatment

ULN = Upper limit of normal. n = Number of subjects assessed.
Grade 3/4 Laboratory Abnormalities	Abacavir plus Lamivudine plus Efavirenz (n = 324)	Zidovudine plus Lamivudine plus Efavirenz (n = 325)
Elevated CPK (>4 X ULN)	8%	8%
Elevated ALT (>5 X ULN)	6%	6%
Elevated AST (>5 X ULN)	6%	5%
Hypertriglyceridemia (>750 mg/dL)	6%	5%
Hyperamylasemia (>2 X ULN)	4%	5%
Neutropenia (ANC <750/mm 3)	2%	4%
Anemia (Hgb 6.9 gm/dL)	<1%	2%
Thrombocytopenia (Platelets <50,000/mm 3)	1%	<1%
Leukopenia (WBC 1,500/mm 3)	<1%	2%

Laboratory abnormalities in CNA3005 are listed in Table 5.

Table 5. Treatment-Emergent Laboratory Abnormalities (Grades 3 to 4) in CNA3005

ULN = Upper limit of normal. n = Number of subjects assessed.
Grade 3/4 Laboratory Abnormalities	Abacavir plus Lamivudine/Zidovudine (n = 262)	Indinavir plus Lamivudine/Zidovudine (n = 264)
Elevated CPK (>4 x ULN)	18 (7%)	18 (7%)
ALT (>5 x ULN)	16 (6%)	16 (6%)
Neutropenia (<750/mm 3)	13 (5%)	13 (5%)
Hypertriglyceridemia (>750 mg/dL)	5 (2%)	3 (1%)
Hyperamylasemia (>2 x ULN)	5 (2%)	1 (<1%)
Hyperglycemia (>13.9 mmol/L)	2 (<1%)	2 (<1%)
Anemia (Hgb 6.9 g/dL)	0 (0%)	3 (1%)

The frequencies of treatment-emergent laboratory abnormalities were comparable between treatment groups in CNA30021.

6.2 Clinical Trials Experience in Pediatric Subjects

Therapy-Experienced Pediatric Subjects (Twice-Daily Dosing)
Treatment-emergent clinical adverse reactions (rated by the investigator as moderate or severe) with a greater than or equal to 5% frequency during therapy with abacavir 8 mg per kg twice daily, lamivudine 4 mg per kg twice daily, and zidovudine 180 mg per m 2 twice daily compared with lamivudine 4 mg per kg twice daily and zidovudine 180 mg per m 2 twice daily from CNA3006 are listed in Table 6.

Table 6. Treatment-Emergent (All Causality) Adverse Reactions of at Least Moderate Intensity (Grades 2 to 4, Greater than or Equal to 5% Frequency) in Therapy-Experienced Pediatric Subjects (CNA3006) through 16 Weeks of Treatment

Adverse Reaction	Abacavir plus Lamivudine plus Zidovudine (n = 102)	Lamivudine plus Zidovudine (n = 103)
Fever and/or chills	9%	7%
Nausea and vomiting	9%	2%
Skin rashes	7%	1%
Ear/nose/throat infections	5%	1%
Pneumonia	4%	5%
Headache	1%	5%

Laboratory Abnormalities: In CNA3006, laboratory abnormalities (anemia, neutropenia, liver function test abnormalities, and CPK elevations) were observed with similar frequencies as in a trial of therapy-naive adults (CNA30024). Mild elevations of blood glucose were more frequent in pediatric subjects receiving abacavir (CNA3006) as compared with adult subjects (CNA30024).

Other Adverse Events
In addition to adverse reactions and laboratory abnormalities reported in Tables 2, 3, 4, 5, and 6, other adverse reactions observed in the expanded access program were pancreatitis and increased GGT.

Additional pediatric use information for patients aged 3 months and above is approved for ViiV Healthcare Company s ZIAGEN (abacavir sulfate) tablets. However, due to ViiV Healthcare Company s marketing exclusivity rights, this drug product is not labeled with that pediatric information.

6.3 Postmarketing Experience

The following adverse reactions have been identified during postmarketing use of abacavir. Because these reactions are reported voluntarily from a population of unknown size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposures.

Body as a Whole
Redistribution/accumulation of body fat.

Cardiovascular
Myocardial infarction.

Hepatic
Lactic acidosis and hepatic steatosis [see Warnings and Precautions (5.2)] .

Skin
Suspected Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) have been reported in patients receiving abacavir primarily in combination with medications known to be associated with SJS and TEN, respectively. Because of the overlap of clinical signs and symptoms between hypersensitivity to abacavir and SJS and TEN, and the possibility of multiple drug sensitivities in some patients, abacavir should be discontinued and not restarted in such cases.

There have also been reports of erythema multiforme with abacavir use [see Adverse Reactions (6.1)] .

7 Drug Interactions ⮝

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.

8 Use In Specific Populations ⮝

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. reference population for birth defects in the general population. The MACDP evaluates women and infants from a limited geographic area and does not include outcomes for births that occurred at less than 20 weeks gestation. The rate of miscarriage is not reported in the APR. The estimated background rate of miscarriage in clinically recognized pregnancies in the U.S. general population is 15% to 20%. The background risk for major birth defects and miscarriage for the indicated population is unknown.

In animal reproduction studies, oral administration of abacavir to pregnant rats during organogenesis resulted in fetal malformations and other embryonic and fetal toxicities at exposures 35 times the human exposure (AUC) at the recommended clinical daily dose. However, no adverse developmental effects were observed following oral administration of abacavir to pregnant rabbits during organogenesis, at exposures approximately 9 times the human exposure (AUC) at the recommended clinical dose [see Data].

Data
Human Data: Based on prospective reports to the APR of over 2,000 exposures to abacavir during pregnancy resulting in live births (including over 1,000 exposed in the first trimester), there was no difference between the overall risk of birth defects for abacavir compared with the background birth defect rate of 2.7% in the U.S. reference population of the MACDP. The prevalence of defects in live births was 2.9% (95% CI: 2.0% to 4.1%) following first trimester exposure to abacavir-containing regimens and 2.7% (95% CI: 1.9% to 3.7%) following second/third trimester exposure to abacavir-containing regimens.

Abacavir has been shown to cross the placenta and concentrations in neonatal plasma at birth were essentially equal to those in maternal plasma at delivery [see Clinical Pharmacology (12.3)] .

Animal Data: Abacavir was administered orally to pregnant rats (at 100, 300, and 1,000 mg per kg per day) and rabbits (at 125, 350, or 700 mg per kg per day) during organogenesis (on gestation Days 6 through 17 and 6 through 20, respectively). Fetal malformations (increased incidences of fetal anasarca and skeletal malformations) or developmental toxicity (decreased fetal body weight and crown-rump length) were observed in rats at doses up to 1,000 mg per kg per day, resulting in exposures approximately 35 times the human exposure (AUC) at the recommended daily dose. No developmental effects were observed in rats at 100 mg per kg per day, resulting in exposures (AUC) 3.5 times the human exposure at the recommended daily dose. In a fertility and early embryo-fetal development study conducted in rats (at 60, 160, or 500 mg per kg per day), embryonic and fetal toxicities (increased resorptions, decreased fetal body weights) or toxicities to the offspring (increased incidence of stillbirth and lower body weights) occurred at doses up to 500 mg per kg per day. No developmental effects were observed in rats at 60 mg per kg per day, resulting in exposures (AUC) approximately 4 times the human exposure at the recommended daily dose. Studies in pregnant rats showed that abacavir is transferred to the fetus through the placenta. In pregnant rabbits, no developmental toxicities and no increases in fetal malformations occurred at up to the highest dose evaluated, resulting in exposures (AUC) approximately 9 times the human exposure at the recommended dose.

8.2 Lactation

Risk Summary
The Centers for Disease Control and Prevention recommend that HIV-1-infected mothers in the United States not breastfeed their infants to avoid risking postnatal transmission of HIV-1 infection. Abacavir is present in human milk. There is no information on the effects of abacavir on the breastfed infant or the effects of the drug on milk production. Because of the potential for (1) HIV-1 transmission (in HIV-negative infants), (2) developing viral resistance (in HIV-positive infants), and (3) serious adverse reactions in a breastfed infant, instruct mothers not to breastfeed if they are receiving abacavir.

8.4 Pediatric Use

The safety and effectiveness of abacavir have been established in pediatric patients aged 3 months and older. Use of abacavir is supported by pharmacokinetic trials and evidence from adequate and well-controlled trials of abacavir in adults and pediatric subjects [see Dosage and Administration (2.2), Adverse Reactions (6.2), Clinical Pharmacology (12.3), Clinical Studies (14.2)].

8.5 Geriatric Use

Clinical trials of abacavir did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. In general, caution should be exercised in the administration of abacavir in elderly patients reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.

8.6 Patients with Impaired Hepatic Function

A dose reduction is required for patients with mild hepatic impairment (Child-Pugh Class A) [see Dosage and Administration (2.4)] . The safety, efficacy, and pharmacokinetic properties of abacavir have not been established in patients with moderate or severe hepatic impairment; therefore, abacavir is contraindicated in these patients [see Contraindications (4), Clinical Pharmacology (12.3)] .

10 Overdosage ⮝

There is no known specific treatment for overdose with abacavir. If overdose occurs, the patient should be monitored and standard supportive treatment applied as required. It is not known whether abacavir can be removed by peritoneal dialysis or hemodialysis.

11 Description ⮝

Abacavir sulfate is a synthetic carbocyclic nucleoside analogue with inhibitory activity against HIV-1. The chemical name of abacavir sulfate is (1 S,cis)-4-[2-amino-6-(cyclopropylamino)-9 H-purin-9-yl]-2-cyclopentene-1-methanol sulfate (salt) (2:1). Abacavir sulfate is the enantiomer with 1S, 4R absolute configuration on the cyclopentene ring. It has a molecular formula of (C 14H 18N 6O) 2 H 2SO 4 and a molecular weight of 670.76 g per mol. It has the following structural formula:

Abacavir sulfate USP is a white to off-white solid and is soluble in water.

Abacavir tablets USP are for oral administration. Each tablet contains abacavir sulfate USP equivalent to 300 mg of abacavir as active ingredient and the following inactive ingredients: colloidal silicon dioxide, magnesium stearate, microcrystalline cellulose, and sodium starch glycolate. The tablets are coated with a film that is made of hypromellose, iron oxide yellow, polysorbate 80, titanium dioxide, and triacetin.

In vivo, abacavir sulfate dissociates to its free base, abacavir. Dosages are expressed in terms of abacavir.

12 Clinical Pharmacology ⮝

12.1 Mechanism of Action

Abacavir is an antiretroviral agent [see Microbiology (12.4)] .

12.3 Pharmacokinetics

Pharmacokinetics in Adults
The pharmacokinetic properties of abacavir were independent of dose over the range of 300 to 1,200 mg per day.

Absorption and Bioavailability: Following oral administration, abacavir is rapidly absorbed and extensively distributed. The geometric mean absolute bioavailability of the tablet was 83%. Plasma abacavir AUC was similar following administration of the oral solution or tablets. After oral administration of 300 mg twice daily in 20 subjects, the steady-state peak serum abacavir concentration (C max) was 3 0.89 mcg per mL (mean SD) and AUC (0-12 h) was 6.02 1.73 mcg hour per mL. After oral administration of a single dose of 600 mg of abacavir in 20 subjects, C max was 4.26 1.19 mcg per mL (mean SD) and AUC was 11.95 2.51 mcg hour per mL.

Distribution: The apparent volume of distribution after IV administration of abacavir was 0.86 0.15 L per kg, suggesting that abacavir distributes into extravascular space. In 3 subjects, the CSF AUC (0-6 h) to plasma abacavir AUC (0-6 h) ratio ranged from 27% to 33%.

Binding of abacavir to human plasma proteins is approximately 50% and was independent of concentration. Total blood and plasma drug-related radioactivity concentrations are identical, demonstrating that abacavir readily distributes into erythrocytes.

Metabolism and Elimination: In humans, abacavir is not significantly metabolized by cytochrome P450 enzymes. The primary routes of elimination of abacavir are metabolism by alcohol dehydrogenase to form the 5 -carboxylic acid and glucuronyl transferase to form the 5 -glucuronide. The metabolites do not have antiviral activity. In vitro experiments reveal that abacavir does not inhibit human CYP3A4, CYP2D6, or CYP2C9 activity at clinically relevant concentrations.

Elimination of abacavir was quantified in a mass balance trial following administration of a 600 mg dose of 14C-abacavir: 99% of the radioactivity was recovered, 1.2% was excreted in the urine as abacavir, 30% as the 5 -carboxylic acid metabolite, 36% as the 5 -glucuronide metabolite, and 15% as unidentified minor metabolites in the urine. Fecal elimination accounted for 16% of the dose.

In single-dose trials, the observed elimination half-life (t 1/2) was 1.54 0.63 hours. After intravenous administration, total clearance was 0.8 0.24 L per hour per kg (mean SD).

Effects of Food on Oral Absorption
Bioavailability of abacavir tablets was assessed in the fasting and fed states with no significant difference in systemic exposure (AUC ); therefore, abacavir tablets may be administered with or without food. Systemic exposure to abacavir was comparable after administration of abacavir oral solution and abacavir tablets. Therefore, these products may be used interchangeably.

Specific Populations
Renal Impairment: The pharmacokinetic properties of abacavir have not been determined in patients with impaired renal function. Renal excretion of unchanged abacavir is a minor route of elimination in humans.

Hepatic Impairment: The pharmacokinetics of abacavir have been studied in subjects with mild hepatic impairment (Child-Pugh Class A). Results showed that there was a mean increase of 89% in the abacavir AUC and an increase of 58% in the half-life of abacavir after a single dose of 600 mg of abacavir. The AUCs of the metabolites were not modified by mild liver disease; however, the rates of formation and elimination of the metabolites were decreased [see Contraindications (4), Use in Specific Populations (8.6)] .

Pregnancy: Abacavir : Abacavir pharmacokinetics were studied in 25 pregnant women during the last trimester of pregnancy receiving abacavir 300 mg twice daily. Abacavir exposure (AUC) during pregnancy was similar to those in postpartum and in HIV-infected non-pregnant historical controls. Consistent with passive diffusion of abacavir across the placenta, abacavir concentrations in neonatal plasma cord samples at birth were essentially equal to those in maternal plasma at delivery.

Pediatric Patients: The pharmacokinetics of abacavir have been studied after either single or repeat doses of abacavir in pediatric subjects. Subjects receiving abacavir oral solution according to the recommended dosage regimen achieved plasma concentrations of abacavir similar to adults. Subjects receiving abacavir oral tablets achieved higher plasma concentrations of abacavir than subjects receiving oral solution.

Additional pediatric use information for patients aged 3 months and above is approved for ViiV Healthcare Company s ZIAGEN (abacavir sulfate) tablets. However, due to ViiV Healthcare Company s marketing exclusivity rights, this drug product is not labeled with that pediatric information.

Geriatric Patients: The pharmacokinetics of abacavir have not been studied in subjects older than 65 years.

Gender: A population pharmacokinetic analysis in HIV-1-infected male (n = 304) and female (n = 67) subjects showed no gender differences in abacavir AUC normalized for lean body weight.

Race: There are no significant or clinically relevant racial differences between blacks and whites in abacavir pharmacokinetics.

Drug Interactions
In human liver microsomes, abacavir did not inhibit cytochrome P450 isoforms (2C9, 2D6, 3A4). Based on these data, it is unlikely that clinically significant drug interactions will occur between abacavir and drugs metabolized through these pathways.

Lamivudine and/or Zidovudine: Fifteen HIV-1-infected subjects were enrolled in a crossover-designed drug interaction trial evaluating single doses of abacavir (600 mg), lamivudine (150 mg), and zidovudine (300 mg) alone or in combination. Analysis showed no clinically relevant changes in the pharmacokinetics of abacavir with the addition of lamivudine or zidovudine or the combination of lamivudine and zidovudine. Lamivudine exposure (AUC decreased 15%) and zidovudine exposure (AUC increased 10%) did not show clinically relevant changes with concurrent abacavir.

Ethanol: Abacavir has no effect on the pharmacokinetic properties of ethanol. Ethanol decreases the elimination of abacavir causing an increase in overall exposure. Due to the common metabolic pathways of abacavir and ethanol via alcohol dehydrogenase, the pharmacokinetic interaction between abacavir and ethanol was studied in 24 HIV-1-infected male subjects. Each subject received the following treatments on separate occasions: a single 600 mg dose of abacavir, 0.7 g per kg ethanol (equivalent to 5 alcoholic drinks), and abacavir 600 mg plus 0.7 g per kg ethanol. Coadministration of ethanol and abacavir resulted in a 41% increase in abacavir AUC and a 26% increase in abacavir t 1/2. Abacavir had no effect on the pharmacokinetic properties of ethanol, so no clinically significant interaction is expected in men. This interaction has not been studied in females.

Methadone: In a trial of 11 HIV-1-infected subjects receiving methadone-maintenance therapy (40 mg and 90 mg daily), with 600 mg of abacavir twice daily (twice the currently recommended dose), oral methadone clearance increased 22% (90% CI: 6% to 42%). 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 [see Drug Interactions (7)] . The addition of methadone had no clinically significant effect on the pharmacokinetic properties of abacavir.

12.4 Microbiology

Abacavir is a carbocyclic synthetic nucleoside analogue. Abacavir is converted by cellular enzymes to the active metabolite, carbovir triphosphate (CBV-TP), an analogue of deoxyguanosine-5 -triphosphate (dGTP). CBV-TP inhibits the activity of HIV-1 reverse transcriptase (RT) both by competing with the natural substrate dGTP and by its incorporation into viral DNA.

Antiviral Activity
The antiviral activity of abacavir against HIV-1 was assessed in a number of cell lines including primary monocytes/macrophages and peripheral blood mononuclear cells (PBMCs). EC 50 values ranged from 3.7 to 5.8 microM (1 microM = 0.28 mcg per mL) and 0.07 to 1 microM against HIV-1 IIIB and HIV-1 BaL, respectively, and the mean EC 50 value was 0.26 0.18 microM against 8 clinical isolates. The median EC 50 values of abacavir were 344 nM (range: 14.8 to 676 nM), 16.9 nM (range: 5.9 to 27.9 nM), 8.1 nM (range: 1.5 to 16.7 nM), 356 nM (range: 35.7 to 396 nM), 105 nM (range: 28.1 to 168 nM), 47.6 nM (range: 5.2 to 200 nM), 51.4 nM (range: 7.1 to 177 nM), and 282 nM (range: 22.4 to 598 nM) against HIV-1 clades A-G and group O viruses (n = 3 except n = 2 for clade B), respectively. The EC 50 values against HIV-2 isolates (n = 4), ranged from 0.024 to 0.49 microM. The antiviral activity of abacavir in cell culture was not antagonized when combined with the nucleoside reverse transcriptase inhibitors (NRTIs) didanosine, emtricitabine, lamivudine, stavudine, tenofovir, zalcitabine or zidovudine, the non-nucleoside reverse transcriptase inhibitor (NNRTI) nevirapine, or the protease inhibitor (PI) amprenavir. Ribavirin (50 microM) used in the treatment of chronic HCV infection had no effect on the anti HIV-1 activity of abacavir in cell culture.

Resistance
HIV-1 isolates with reduced susceptibility to abacavir have been selected in cell culture. Genotypic analysis of isolates selected in cell culture and recovered from abacavir-treated subjects demonstrated that amino acid substitutions K65R, L74V, Y115F, and M184V/I emerged in HIV-1 RT. M184V or I substitutions resulted in an approximately 2-fold decrease in susceptibility to abacavir. Substitutions K65R, L74M, or Y115F with M184V or I conferred a 7-to 8-fold reduction in abacavir susceptibility, and combinations of three substitutions were required to confer more than an 8-fold reduction in susceptibility.

Thirty-nine percent (7 of 18) of the isolates from subjects who experienced virologic failure in the abacavir once-daily arm had a greater than 2.5-fold mean decrease in abacavir susceptibility with a median-fold decrease of 1.3 (range: 0.5 to 11) compared with 29% (5 of 17) of the failure isolates in the twice-daily arm with a median-fold decrease of 0.92 (range: 0.7 to 13).

Cross-Resistance
Cross-resistance has been observed among NRTIs. Isolates containing abacavir resistance-associated substitutions, namely, K65R, L74V, Y115F, and M184V, exhibited cross-resistance to didanosine, emtricitabine, lamivudine, and tenofovir in cell culture and in subjects. An increasing number of thymidine analogue mutation substitutions (TAMs: M41L, D67N, K70R, L210W, T215Y/F, K219E/R/H/Q/N) is associated with a progressive reduction in abacavir susceptibility.

13 Nonclinical Toxicology ⮝

13.1 Carcinogenesis, Mutagenesis, Impairment of Fertility

Carcinogenicity
Abacavir was administered orally at 3 dosage levels to separate groups of mice and rats in 2-year carcinogenicity studies. Results showed an increase in the incidence of malignant and non-malignant tumors. Malignant tumors occurred in the preputial gland of males and the clitoral gland of females of both species, and in the liver of female rats. In addition, non-malignant tumors also occurred in the liver and thyroid gland of female rats. These observations were made at systemic exposures in the range of 6 to 32 times the human exposure at the recommended dose of 600 mg.

Mutagenicity
Abacavir induced chromosomal aberrations both in the presence and absence of metabolic activation in an in vitro cytogenetic study in human lymphocytes. Abacavir was mutagenic in the absence of metabolic activation, although it was not mutagenic in the presence of metabolic activation in an L5178Y mouse lymphoma assay. Abacavir was clastogenic in males and not clastogenic in females in an in vivo mouse bone marrow micronucleus assay.

Abacavir was not mutagenic in bacterial mutagenicity assays in the presence and absence of metabolic activation.

Impairment of Fertility
Abacavir did not affect male or female fertility in rats at a dose associated with exposures (AUC) approximately 3.3 times (male) or 4.1 times (female) those in humans at the clinically recommended dose.

13.2 Animal Toxicology and/or Pharmacology

Myocardial degeneration was found in mice and rats following administration of abacavir for 2 years. The systemic exposures were equivalent to 7 to 24 times the expected systemic exposure in humans at a dose of 600 mg. The clinical relevance of this finding has not been determined.

14 Clinical Studies ⮝

14.1 Adult Trials

Therapy-Naive Adults
CNA30024 was a multicenter, double-blind, controlled trial in which 649 HIV-1-infected, therapy-naive adults were randomized and received either abacavir (300 mg twice daily), lamivudine (150 mg twice daily), and efavirenz (600 mg once daily); or zidovudine (300 mg twice daily), lamivudine (150 mg twice daily), and efavirenz (600 mg once daily). The duration of double-blind treatment was at least 48 weeks. Trial participants were male (81%), white (51%), black (21%), and Hispanic (26%). The median age was 35 years; the median pretreatment CD4+ cell count was 264 cells per mm 3, and median plasma HIV-1 RNA was 4.79 log 10 copies per mL. The outcomes of randomized treatment are provided in Table 7.

Table 7. Outcomes of Randomized Treatment through Week 48 (CNA30024)

* Subjects achieved and maintained confirmed HIV-1 RNA less than or equal to 50 copies per mL (less than 400 copies per mL) through Week 48 (Roche AMPLICOR Ultrasensitive HIV-1 MONITOR standard test 1 PCR). Includes viral rebound, insufficient viral response according to the investigator, and failure to achieve confirmed less than or equal to 50 copies per mL by Week 48. Includes consent withdrawn, lost to follow up, protocol violations, those with missing data, clinical progression, and other.
Outcome	Abacavir plus Lamivudine plus Efavirenz (n = 324)	Zidovudine plus Lamivudine plus Efavirenz (n = 325)
Responder *	69% (73%)	69% (71%)
Virologic failures	6%	4%
Discontinued due to adverse reactions	14%	16%
Discontinued due to other reasons	10%	11%

After 48 weeks of therapy, the median CD4+ cell count increases from baseline were 209 cells per mm 3 in the group receiving abacavir and 155 cells per mm 3 in the zidovudine group. Through Week 48, 8 subjects (2%) in the group receiving abacavir (5 CDC classification C events and 3 deaths) and 5 subjects (2%) on the zidovudine arm (3 CDC classification C events and 2 deaths) experienced clinical disease progression.

CNA3005 was a multicenter, double-blind, controlled trial in which 562 HIV-1-infected, therapy-naive adults were randomized to receive either abacavir (300 mg twice daily) plus COMBIVIR (lamivudine 150 mg/zidovudine 300 mg twice daily), or indinavir (800 mg 3 times a day) plus COMBIVIR twice daily. The trial was stratified at randomization by pre-entry plasma HIV-1 RNA 10,000 to 100,000 copies per mL and plasma HIV-1 RNA greater than 100,000 copies per mL. Trial participants were male (87%), white (73%), black (15%), and Hispanic (9%). At baseline the median age was 36 years; the median baseline CD4+ cell count was 360 cells per mm 3, and median baseline plasma HIV-1 RNA was 4.8 log 10 copies per mL. Proportions of subjects with plasma HIV-1 RNA less than 400 copies per mL (using Roche AMPLICOR HIV-1 MONITOR Test) through 48 weeks of treatment are summarized in Table 8.

Table 8. Outcomes of Randomized Treatment through Week 48 (CNA3005)

* Subjects achieved and maintained confirmed HIV-1 RNA less than 400 copies per mL. Includes viral rebound and failure to achieve confirmed less than 400 copies per mL by Week 48. Includes consent withdrawn, lost to follow up, protocol violations, those with missing data, clinical progression, and other.
Outcome	Abacavir plus Lamivudine/Zidovudine (n = 262)	Indinavir plus Lamivudine/Zidovudine (n = 265)
Responder *	49%	50%
Virologic failure	31%	28%
Discontinued due to adverse reactions	10%	12%
Discontinued due to other reasons	11%	10%

Treatment response by plasma HIV-1 RNA strata is shown in Table 9.

Table 9. Proportions of Responders through Week 48 by Screening Plasma HIV-1 RNA Levels (CNA3005)

Screening HIV-1 RNA (copies/mL)	Abacavir plus Lamivudine/Zidovudine (n = 262)		Indinavir plus Lamivudine/Zidovudine (n = 265)
	<400 copies/mL	n	<400 copies/mL	n
10,000 to 100,000 >100,000	50% 48%	166 96	48% 52%	165 100

In subjects with baseline viral load greater than 100,000 copies per mL, percentages of subjects with HIV-1 RNA levels less than 50 copies per mL were 31% in the group receiving abacavir versus 45% in the group receiving indinavir.

Through Week 48, an overall mean increase in CD4+ cell count of about 150 cells per mm 3 was observed in both treatment arms. Through Week 48, 9 subjects (3.4%) in the group receiving abacavir (6 CDC classification C events and 3 deaths) and 3 subjects (1.5%) in the group receiving indinavir (2 CDC classification C events and 1 death) experienced clinical disease progression.

CNA30021 was an international, multicenter, double-blind, controlled trial in which 770 HIV-1-infected, therapy-naive adults were randomized and received either abacavir 600 mg once daily or abacavir 300 mg twice daily, both in combination with lamivudine 300 mg once daily and efavirenz 600 mg once daily. The double-blind treatment duration was at least 48 weeks. Trial participants had a mean age of 37 years; were male (81%), white (54%), black (27%), and American Hispanic (15%). The median baseline CD4+ cell count was 262 cells per mm 3 (range: 21 to 918 cells per mm 3) and the median baseline plasma HIV-1 RNA was 4.89 log 10 copies per mL (range: 2.6 to 6.99 log 10 copies per mL).

The outcomes of randomized treatment are provided in Table 10.

Table 10. Outcomes of Randomized Treatment through Week 48 (CNA30021)

* Subjects achieved and maintained confirmed HIV-1 RNA less than 50 copies per mL (less than 400 copies per mL) through Week 48 (Roche AMPLICOR Ultrasensitive HIV-1 MONITOR standard test version 1). Includes viral rebound, failure to achieve confirmed less than 50 copies per mL (less than 400 copies per mL) by Week 48, and insufficient viral load response. Includes consent withdrawn, lost to follow up, protocol violations, clinical progression, and other.
Outcome	Abacavir 600 mg q.d. plus EPIVIR plus Efavirenz (n = 384)	Abacavir 300 mg b.i.d. plus EPIVIR plus Efavirenz (n = 386)
Responder *	64% (71%)	65% (72%)
Virologic failure	11% (5%)	11% (5%)
Discontinued due to adverse reactions	13%	11%
Discontinued due to other reasons	11%	13%

After 48 weeks of therapy, the median CD4+ cell count increases from baseline were 188 cells per mm 3 in the group receiving abacavir 600 mg once daily and 200 cells per mm 3 in the group receiving abacavir 300 mg twice daily. Through Week 48, 6 subjects (2%) in the group receiving abacavir 600 mg once daily (4 CDC classification C events and 2 deaths) and 10 subjects (3%) in the group receiving abacavir 300 mg twice daily (7 CDC classification C events and 3 deaths) experienced clinical disease progression. None of the deaths were attributed to trial medications.

14.2 Pediatric Trials

Therapy-Experienced Pediatric Subjects
CNA3006 was a randomized, double-blind trial comparing abacavir 8 mg per kg twice daily plus lamivudine 4 mg per kg twice daily plus zidovudine 180 mg per m 2 twice daily versus lamivudine 4 mg per kg twice daily plus zidovudine 180 mg per m 2 twice daily. Two hundred and five therapy-experienced pediatric subjects were enrolled: female (56%), white (17%), black (50%), Hispanic (30%), median age of 5.4 years, baseline CD4+ cell percent greater than 15% (median = 27%), and median baseline plasma HIV-1 RNA of 4.6 log 10 copies per mL. Eighty percent and 55% of subjects had prior therapy with zidovudine and lamivudine, respectively, most often in combination. The median duration of prior nucleoside analogue therapy was 2 years. At 16 weeks the proportion of subjects responding based on plasma HIV-1 RNA less than or equal to 400 copies per mL was significantly higher in subjects receiving abacavir plus lamivudine plus zidovudine compared with subjects receiving lamivudine plus zidovudine, 13% versus 2%, respectively. Median plasma HIV-1 RNA changes from baseline were -0.53 log 10 copies per mL in the group receiving abacavir plus lamivudine plus zidovudine compared with -0.21 log 10 copies per mL in the group receiving lamivudine plus zidovudine. Median CD4+ cell count increases from baseline were 69 cells per mm 3 in the group receiving abacavir plus lamivudine plus zidovudine and 9 cells per mm 3 in the group receiving lamivudine plus zidovudine.

Additional pediatric use information for patients aged 3 months and above is approved for ViiV Healthcare Company s ZIAGEN (abacavir sulfate) tablets. However, due to ViiV Healthcare Company s marketing exclusivity rights, this drug product is not labeled with that pediatric information.

16 How Supplied/storage And Handling ⮝

Abacavir tablets USP, containing abacavir sulfate equivalent to 300 mg abacavir, are yellow colored, biconvex, capsule shaped, coated tablet, debossed with D and 88 on either side of the score line on one side and plain with a score line on other side. They are packaged as follows:
Unit dose packages of 30 (3 x 10) NDC 68084-021-21

Store at 20 to 25 C (68 to 77 F); excursions permitted to 15 to 30 C (59 to 86 F) [ see USP Controlled Room Temperature] .

FOR YOUR PROTECTION: Do not use if blister is torn or broken.

Packaging Information ⮝

American Health Packaging unit dose blisters (see How Supplied section) contain drug product from Aurobindo Pharma USA, Inc. as follows:
(300 mg / 30 UD) NDC 68084-021-21 packaged from NDC 65862-073

Distributed by:
American Health Packaging
Columbus, OH 43217

8202121/0817OS

Package/label Display Panel Carton 300 Mg ⮝

NDC 68084- 021-21

Abacavir
Tablets USP

300 mg

30 Tablets (3 x 10) Rx Only

PHARMACIST: Dispense with the accompanying Medication
Guide and Warning Card to each patient.

Each Film-Coated Tablet Contains:
Abacavir sulfate USP equivalent to 300 mg of abacavir.

Usual Dosage: See package insert for full prescribing
information.

Store at 20 to 25 C (68 to 77 F); excursions permitted between
15 to 30 C (59 to 86 F) [see USP Controlled Room Temperature].

Keep this and all drugs out of reach of children.

FOR YOUR PROTECTION: Do not use if blister is torn or broken.

The drug product contained in this package is from
NDC # 65862-073, Aurobindo Pharma USA, Inc.

Distributed by:
American Health Packaging
Columbus, Ohio 43217

002121
0202121/0918OS

Package/label Display Panel Blister 300 Mg ⮝

Abacavir
Tablet USP

300 mg

ABACAVIR abacavir sulfate tablet, film coated

Product Information Product Type HUMAN PRESCRIPTION DRUG Item Code (Source) NDC:68084-021(NDC:65862-073) Route of Administration ORAL

Active Ingredient/Active Moiety Ingredient Name Basis of Strength Strength ABACAVIR SULFATE (UNII: J220T4J9Q2) (ABACAVIR - UNII:WR2TIP26VS) ABACAVIR 300 mg

Inactive Ingredients Ingredient Name Strength SILICON DIOXIDE (UNII: ETJ7Z6XBU4) MAGNESIUM STEARATE (UNII: 70097M6I30) MICROCRYSTALLINE CELLULOSE (UNII: OP1R32D61U) SODIUM STARCH GLYCOLATE TYPE A POTATO (UNII: 5856J3G2A2) HYPROMELLOSE, UNSPECIFIED (UNII: 3NXW29V3WO) FERRIC OXIDE YELLOW (UNII: EX438O2MRT) POLYSORBATE 80 (UNII: 6OZP39ZG8H) TITANIUM DIOXIDE (UNII: 15FIX9V2JP) TRIACETIN (UNII: XHX3C3X673)

Product Characteristics Color yellow Score 2 pieces Shape CAPSULE (Biconvex) Size 18mm Flavor Imprint Code D;88 Contains

Packaging # Item Code Package Description Marketing Start Date Marketing End Date 1 NDC:68084-021-21 30 in 1 BOX, UNIT-DOSE 01/24/2013 1 NDC:68084-021-11 1 in 1 BLISTER PACK; Type 0: Not a Combination Product

Marketing Information Marketing Category Application Number or Monograph Citation Marketing Start Date Marketing End Date ANDA ANDA077844 01/24/2013

Labeler - American Health Packaging (929561009)

Establishment
Name	Address	ID/FEI	Business Operations
American Health Packaging		929561009	repack(68084-021)

Revised: 9/2018 Document Id: 76257690-2f30-2751-e053-2991aa0a64b9 34391-3 Set id: 01e46f58-8bda-4ff3-ab21-57d5b540d440 Version: 4 Effective Time: 20180918 American Health Packaging