ISENTRESS
(raltegravir) Tablets
ISENTRESS contains raltegravir potassium, a human immunodeficiency virus integrase strand transfer inhibitor. The chemical name for raltegravir potassium is N-[(4-Fluorophenyl)methyl]-1,6-dihydro5-hydroxy-1-methyl-2-[1-methyl-1-[[(5-methyl-1,3,4-oxadiazol-2-yl)carbonyl]amino]ethyl]-6-oxo-4pyrimidinecarboxamide monopotassium salt.
The empirical formula is C20H20FKN6O5 and the molecular weight is 482.51. The structural formula is:
 |
Raltegravir potassium is a white to off-white powder. It is soluble in water, slightly soluble in methanol, very slightly soluble in ethanol and acetonitrile and insoluble in isopropanol.
Each film-coated tablet of ISENTRESS for oral administration contains 434.4 mg of raltegravir potassium (as salt), equivalent to 400 mg of raltegravir (free phenol) and the following inactive ingredients: microcrystalline cellulose, lactose monohydrate, calcium phosphate dibasic anhydrous, hypromellose 2208, poloxamer 407 (contains 0.01% butylated hydroxytoluene as antioxidant), sodium stearyl fumarate, magnesium stearate. In addition, the film coating contains the following inactive ingredients: polyvinyl alcohol, titanium dioxide, polyethylene glycol 3350, talc, red iron oxide and black iron oxide.
Last updated on RxList: 7/21/2009
ISENTRESS is indicated in combination with other anti-retroviral agents for the treatment of human immunodeficiency virus (HIV-1) infection in adult patients.
This indication is based on analyses of plasma HIV-1 RNA levels up through 48 weeks in three double-blind controlled studies of ISENTRESS. Two of these studies were conducted in clinically advanced, 3-class antiretroviral (NNRTI, NRTI, PI) treatment-experienced adults and one was conducted in treatment-naļve adults.
The use of other active agents with ISENTRESS is associated with a greater likelihood of treatment response [see Clinical Studies].
The safety and efficacy of ISENTRESS have not been established in pediatric patients.
For the treatment of patients with HIV-1 infection, the dosage of ISENTRESS is 400 mg administered orally, twice daily with or without food. During coadministration with rifampin, the recommended dosage of ISENTRESS is 800 mg twice daily with or without food.
400 mg pink, oval-shaped, film-coated tablets with “227” on one side.
ISENTRESS tablets 400 mg are pink, oval-shaped, film-coated tablets with “227” on one side. They are supplied as follows:
NDC 0006-0227-61 unit-of-use bottles of 60.
No. 3894
Store at 20-25°C (68-77°F); excursions permitted to 15-30°C (59-86°F). See USP Controlled Room Temperature.
Manufactured and Distributed by: MERCK & CO., INC., Whitehouse Station, NJ 08889, USA.
Last updated on RxList: 7/21/2009
Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.
The following safety assessment of ISENTRESS in treatment-naļve subjects is based on the randomized double-blind active controlled study of treatment-naļve subjects, STARTMRK (Protocol 021) with ISENTRESS 400 mg twice daily in combination with a fixed dose of emtricitabine 200 mg (+) tenofovir 300 mg, (N=281) versus efavirenz (EFV) 600 mg at bedtime in combination with emtricitabine (+) tenofovir, (N=282). During double-blind treatment, the total follow-up for subjects receiving ISENTRESS 400 mg twice daily + emtricitabine (+) tenofovir was 247 patient-years and 241 patient-years for subjects receiving efavirenz 600 mg at bedtime + emtricitabine (+) tenofovir.
In Protocol 021, the rate of discontinuation of therapy due to adverse reactions was 3% in subjects receiving ISENTRESS + emtricitabine (+) tenofovir and 6% in subjects receiving efavirenz + emtricitabine (+) tenofovir.
The clinical adverse drug reactions (ADRs) listed below were considered by investigators to be causally related to ISENTRESS + emtricitabine (+) tenofovir or efavirenz + emtricitabine (+) tenofovir. Clinical ADRs of moderate to severe intensity occurring in ≥ 2% of treatment-naļve subjects treated with ISENTRESS and occurring at a higher rate than efavirenz are presented in Table 1.
Table 1: Adverse Reactions* of Moderate to Severe Intensity†
Occurring in ≥ 2% of Treatment-Naļve Adult Subjects Receiving ISENTRESS and
at a Higher Rate Compared to Efavirenz (48 Week Analysis)
| System Organ Class, Preferred Term | Randomized Study Protocol 021 | |
| ISENTRESS 400 mg Twice Daily + Emtricitabine (+) Tenofovir (n = 281)‡ % |
Efavirenz 600 mg At Bedtime + Emtricitabine (+) Tenofovir (n = 282)‡ % |
|
| Psychiatric Disorders | ||
| Insomnia | 4 | 3 |
| *Includes adverse experiences considered by investigators
to be at least possibly, probably, or definitely related to the drug † Intensities are defined as follows: Moderate (discomfort enough to cause interference with usual activity); Severe (incapacitating with inability to work or do usual activity). ‡ n = total number of subjects per treatment group |
||
The following ADRs occurred in < 2% of subjects receiving ISENTRESS + emtricitabine (+) tenofovir. These events have been included because of their seriousness, increased frequency on ISENTRESS compared with efavirenz or investigator's assessment of potential causal relationship.
General Disorders and Administration Site Conditions: fatigue
Psychiatric Disorders: abnormal dreams
The percentages of adult subjects treated with ISENTRESS 400 mg twice daily or efavirenz in Protocol 021 with selected Grades 2 to 4 laboratory abnormalities that represent a worsening from baseline are presented in Table 2.
Table 2: Selected Grade 2 to 4 Laboratory Abnormalities Reported
in Treatment-Naļve Subjects (48 Week Analysis)
| Laboratory Parameter Preferred Term (Unit) | Limit | Randomized Study Protocol 021 | |
| ISENTRESS 400 mg Twice Daily +Emtricitabine
(+) Tenofovir (N = 281) |
Efavirenz600 mg At Bedtime +Emtricitabine (+) Tenofovir (N = 282) |
||
| Hematology | |||
| Absolute neutrophil count (10³/ μ L) | |||
| Grade 2 | 0.75 - 0.999 | 3% | 3% |
| Grade 3 | 0.50 - 0.749 | 1% | < 1% |
| Grade 4 | < 0.50 | < 1% | 0% |
| Hemoglobin (gm/dL) | |||
| Grade 2 | 7.5 - 8.4 | < 1% | < 1% |
| Grade 3 | 6.5 - 7.4 | < 1% | < 1% |
| Grade 4 | <6.5 | 0% | 0% |
| Platelet count (10³μ / L) | |||
| Grade 2 | 50 - 99.999 | 2% | 0% |
| Grade 3 | 25 - 49.999 | 0% | < 1% |
| Grade 4 | < 25 | 0% | .0% |
| Blood chemistry | |||
| Fasting (non-random) serum glucose test (mg/dL) | |||
| Grade 2 | 126 - 250 | 2% | 3% |
| Grade 3 | 251 - 500 | < 1% | 0% |
| Grade 4 | > 500 | 0% | 0% |
| Total serum bilirubin | |||
| Grade 2 | 1.6 - 2.5 x ULN | 4% | 0% |
| Grade 3 | 2.6 - 5.0 x ULN | < 1% | 0% |
| Grade 4 | > 5.0 x ULN | 0% | 0% |
| Serum aspartate aminotransferase | |||
| Grade 2 | 2.6 - 5.0 x ULN | 3% | 4% |
| Grade 3 | 5.1 - 10.0 x ULN | 1% | 1% |
| Grade 4 | > 10.0 x ULN | < 1% | < 1% |
| Serum alanine aminotransferase | |||
| Grade 2 | 2.6 - 5.0 x ULN | 4% | 6% |
| Grade 3 | 5.1 - 10.0 x ULN | < 1% | 2% |
| Grade 4 | > 10.0 x ULN | < 1% | < 1% |
| Serum alkaline phosphatase | |||
| Grade 2 | 2.6 - 5.0 x ULN | < 1% | 2% |
| Grade 3 | 5.1 - 10.0 x ULN | 0% | < 1% |
| Grade 4 | > 10.0 x ULN | 0% | 0% |
| ULN = Upper limit of normal range | |||
Changes from baseline in fasting lipids are shown in Table 3.
Table 3: Lipid Values, Mean Change from Baseline, Protocol
021
| Laboratory Parameter Preferred Term | ISENTRESS 400 mg Twice Daily + Emtricitabine
(+) Tenofovir N = 281 |
Efavirenz 600 mg At Bedtime + Emtricitabine
(+) Tenofovir N= 282 |
||||
| Change from Baseline at Week 48 | Change from Baseline at Week 48 | |||||
| Baseline Mean (mg/dL) |
Week 48 Mean (mg/dL) |
Mean Change (mg/dL) |
Baseline Mean (mg/dL) |
Week 48 Mean (mg/dL) |
Mean Change (mg/dL) |
|
| LDL-Cholesterol† | 97 | 103 | 6 | 92 | 108 | 16 |
| HDL-Cholesterol† | 38 | 42 | 4 | 38 | 48 | 10 |
| Total Cholesterol† | 159 | 169 | 10 | 156 | 188 | 33 |
| Triglyceride† | 125 | 122 | -3 | 136 | 174 | 37 |
| †Fasting (non-random) laboratory tests. Notes: N = Number of subjects in the treatment group. The analysis is based on all available data. If subjects initiated or increased serum lipid-reducing agents, the last available lipid values prior to the change in therapy were used in the analysis. If the missing data was due to other reasons, subjects were censored thereafter for the analysis. At baseline, serum lipid-reducing agents were used in 5% of subjects in the group receiving ISENTRESS and 3% in the efavirenz group. Through Week 48, serum lipid-reducing agents were used in 6% of subjects in the group receiving ISENTRESS and 6% in the efavirenz group. |
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The safety assessment of ISENTRESS in treatment-experienced subjects is based on the pooled safety data from the randomized, double-blind, placebo-controlled trials, BENCHMRK 1 and BENCHMRK 2 (Protocols 018 and 019) in antiretroviral treatment-experienced HIV-1 infected adult subjects. A total of 462 subjects received the recommended dose of ISENTRESS 400 mg twice daily in combination with optimized background therapy (OBT) compared to 237 subjects taking placebo in combination with OBT. The median duration of therapy in these trials was 48 weeks for subjects receiving ISENTRESS and 38 weeks for subjects receiving placebo. The total exposure to ISENTRESS was 387 patient-years versus 156 patient-years on placebo. The rates of discontinuation due to adverse events were 2% in subjects receiving ISENTRESS and 3% in subjects receiving placebo.
Clinical ADRs were considered by investigators to be causally related to ISENTRESS + OBT or placebo + OBT. Clinical ADRs of moderate to severe intensity occurring in ≥ 2% of subjects treated with ISENTRESS and occurring at a higher exposure adjusted rate compared to placebo are presented in Table 4.
Table 4: Adverse Drug Reactions* of Moderate to Severe Intensity†
Occurring in ≥ 2% of Treatment-Experienced Adult Subjects Receiving ISENTRESS
and at a Higher Exposure Adjusted Rate Compared to Placebo (48 Week Analysis,
Exposure Adjusted Incidence Rates)
| System Organ Class, Adverse Reactions | Randomized Studies Protocol 018 and 019 | |
| ISENTRESS 400 mg Twice Daily+ OBT (n = 462)‡ |
Placebo + OBT (n = 237)‡ |
|
| Rate per 100 Patient-Years | Rate per 100 Patient-Years | |
| Nervous System Disorders | ||
| Headache | 3 | 1 |
| Gastrointestinal Disorders | ||
| Nausea | 2 | 1 |
| General Disorders and Administration Site Conditions | ||
| Asthenia | 2 | 1 |
| Fatigue | 2 | 1 |
| *Includes adverse reactions at least possibly, probably,
or definitely related to the drug. †Intensities are defined as follows: Moderate (discomfort enough to cause interference with usual activity); Severe (incapacitating with inability to work or do usual activity). ‡n=total number of subjects per treatment group. |
||
The following ADRs occurred in < 2% of subjects receiving ISENTRESS + OBT. These events have been included because of either their seriousness, increased frequency on ISENTRESS compared with placebo or investigator's assessment of potential causal relationship.
Gastrointestinal Disorders: abdominal pain, gastritis
Hepatobiliary Disorders: hepatitis
Immune System Disorders: hypersensitivity
Infections and Infestations: genital herpes, herpes zoster
Nervous System Disorders: dizziness
Renal and Urinary Disorders: renal failure
The percentages of adult subjects treated with ISENTRESS 400 mg twice daily or placebo in Protocols 018 and 019 with selected Grade 2 to 4 laboratory abnormalities representing a worsening from baseline are presented in Table 5.
Table 5: Selected Grade 2 to 4 Laboratory Abnormalities Reported
in Treatment-Experienced Subjects (48 Week Analysis)
| Laboratory Parameter Preferred Term(Unit) | Limit | Randomized Studies Protocol 018 and 019 | |
| ISENTRESS 400 mg Twice Daily + OBT (N = 462) |
Placebo + OBT (N = 237) |
||
| Hematology | |||
| Absolute neutrophil count (10³μ / L) | |||
| Grade 2 | 0.75 - 0.999 | 3% | 5% |
| Grade 3 | 0.50 - 0.749 | 3% | 3% |
| Grade 4 | < 0.50 | 1% | < 1% |
| Hemoglobin (gm/dL) | |||
| Grade 2 | 7.5 - 8.4 | 1% | 3% |
| Grade 3 | 6.5 - 7.4 | 1% | < 1% |
| Grade 4 | < 6.5 | < 1% | 0% |
| Platelet count (10³/ μ L) | |||
| Grade 2 | 50 - 99.999 | 3% | 5% |
| Grade 3 | 25 - 49.999 | 1% | < 1% |
| Grade 4 | < 25 | 1% | < 1% |
| Blood chemistry | |||
| Fasting (non-random) serum glucose test (mg/dL) | |||
| Grade 2 | 126 - 250 | 8% | 5% |
| Grade 3 | 251 - 500 | 2% | 1% |
| Grade 4 | > 500 | 0% | 0% |
| Total serum bilirubin | |||
| Grade 2 | 1.6 - 2.5 x ULN | 5% | 3% |
| Grade 3 | 2.6 - 5.0 x ULN | 2% | 2% |
| Grade 4 | > 5.0 x ULN | 1% | 0% |
| Serum aspartate aminotransferase | |||
| Grade 2 | 2.6 - 5.0 x ULN | 8% | 6% |
| Grade 3 | 5.1 - 10.0 x ULN | 3% | 3% |
| Grade 4 | > 10.0 x ULN | < 1% | 1% |
| Serum alanine aminotransferase | |||
| Grade 2 | 2.6 - 5.0 x ULN | 7% | 8% |
| Grade 3 | 5.1 - 10.0 x ULN | 3% | 2% |
| Grade 4 | > 10.0 x ULN | 1% | 2% |
| Serum alkaline phosphatase | |||
| Grade 2 | 2.6 - 5.0 x ULN | 2% | < 1% |
| Grade 3 | 5.1 - 10.0 x ULN | < 1% | 1% |
| Grade 4 | > 10.0 x ULN | 1% | < 1% |
| Serum pancreatic amylase test | |||
| Grade 2 | 1.6 - 2.0 x ULN | 2% | 1% |
| Grade 3 | 2.1 - 5.0 x ULN | 3% | 3% |
| Grade 4 | > 5.0 x ULN | < 1% | 0% |
| Serum lipase test | |||
| Grade 2 | 1.6 - 3.0 x ULN | 4% | 3% |
| Grade 3 | 3.1 - 5.0 x ULN | 1% | < 1% |
| Grade 4 | > 5.0 x ULN | 0% | 0% |
| Serum creatine kinase | |||
| Grade 2 | 6.0 - 9.9 x ULN | 2% | 2% |
| Grade 3 | 10.0 - 19.9 x ULN | 3% | 3% |
| Grade 4 | ≥ 20.0 x ULN | 2% | 1% |
| ULN = Upper limit of normal range | |||
Cancers were reported in treatment-experienced subjects who initiated ISENTRESS or placebo, both with OBT, and in treatment-naļve subjects who initiated ISENTRESS or efavirenz, both with emtricitabine (+) tenofovir; several were recurrent. The types and rates of specific cancers were those expected in a highly immunodeficient population (many had CD4+ counts below 50 cells/mm³ and most had prior AIDS diagnoses). The risk of developing cancer in these studies was similar in the group receiving ISENTRESS and the group receiving the comparator.
Grade 2-4 creatine kinase laboratory abnormalities were observed in subjects treated with ISENTRESS (see Table 5). Myopathy and rhabdomyolysis have been reported; however, the relationship of ISENTRESS to these events is not known. Use with caution in patients at increased risk of myopathy or rhabdomyolysis, such as patients receiving concomitant medications known to cause these conditions.
In the randomized, double-blind, placebo-controlled trials, treatment-experienced subjects (N = 114/699 or 16%) and treatment-naļve subjects (N = 34/563 or 6%) with chronic (but not acute) active hepatitis B and/or hepatitis C virus co-infection were permitted to enroll provided that baseline liver function tests did not exceed 5 times the upper limit of normal (ULN). In general the safety profile of ISENTRESS in subjects with hepatitis B and/or hepatitis C virus co-infection was similar to that in subjects without hepatitis B and/or hepatitis C virus co-infection, although the rates of AST and ALT abnormalities were higher in the subgroup with hepatitis B and/or hepatitis C virus co-infection for all treatment groups. In treatment-experienced subjects, Grade 2 or higher laboratory abnormalities that represent a worsening Grade from baseline of AST, ALT or total bilirubin occurred in 25%, 31% and 12%, respectively, of co-infected subjects treated with ISENTRESS as compared to 8%, 7% and 8% of all other subjects treated with ISENTRESS. In treatment-naļve subjects, Grade 2 or higher laboratory abnormalities that represent a worsening Grade from baseline of AST, ALT or total bilirubin occurred in 17%, 22% and 11%, respectively, of co-infected subjects treated with ISENTRESS as compared to 4%, 4% and 3% of all other subjects treated with ISENTRESS.
The following adverse reactions have been identified during postapproval use of ISENTRESS. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Psychiatric Disorders: anxiety, depression (particularly in patients with a pre-existing history of psychiatric illness), including suicidal ideation and behaviors, paranoia Skin and Subcutaneous Tissue Disorders: rash, Stevens-Johnson syndrome
Raltegravir does not inhibit (IC50 > 100 μM) CYP1A2, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6 or CYP3A in vitro. Moreover, in vitro, raltegravir did not induce CYP1A2, CYP2B6 or CYP3A4. A midazolam drug interaction study confirmed the low propensity of raltegravir to alter the pharmacokinetics of agents metabolized by CYP3A4 in vivo by demonstrating a lack of effect of raltegravir on the pharmacokinetics of midazolam, a sensitive CYP3A4 substrate. Similarly, raltegravir is not an inhibitor (IC50 > 50 μM) of the UDP-glucuronosyltransferases (UGT) tested (UGT1A1, UGT2B7), and raltegravir does not inhibit P-glycoprotein-mediated transport. Based on these data, ISENTRESS is not expected to affect the pharmacokinetics of drugs that are substrates of these enzymes or P-glycoprotein (e.g., protease inhibitors, NNRTIs, opioid analgesics, statins, azole antifungals, proton pump inhibitors and anti-erectile dysfunction agents).
In drug interaction studies, raltegravir did not have a clinically meaningful effect on the pharmacokinetics of the following: hormonal contraceptives, methadone, lamivudine, tenofovir, etravirine.
Raltegravir is not a substrate of cytochrome P450 (CYP) enzymes. Based on in vivo and in vitro studies, raltegravir is eliminated mainly by metabolism via a UGT1A1-mediated glucuronidation pathway.
Rifampin, a strong inducer of UGT1A1, reduces plasma concentrations of ISENTRESS. Therefore, the dose of ISENTRESS should be increased during coadministration with rifampin [see DOSAGE AND ADMINISTRATION]. The impact of other inducers of drug metabolizing enzymes, such as phenytoin and phenobarbital, on UGT1A1 is unknown.
Coadministration of ISENTRESS with drugs that inhibit UGT1A1 may increase plasma levels of raltegravir.
Selected drug interactions are presented in Table 6 [see CLINICAL PHARMACOLOGY].
Table 6: Selected Drug Interactions
| Concomitant Drug Class: Drug Name |
Effect on Concentration of Raltegravir | Clinical Comment |
| HIV-1-Antiviral Agents | ||
| atazanavir | ↑ | Atazanavir, a strong inhibitor of UGT1A1, increases plasma concentrations of raltegravir. However, since concomitant use of ISENTRESS with atazanavir/ritonavir did not result in a unique safety signal in Phase 3 studies, no dose adjustment is recommended. |
| atazanavir/ritonavir | ↑ | Atazanavir/ritonavir increases plasma concentrations of raltegravir. However, since concomitant use of ISENTRESS with atazanavir/ritonavir did not result in a unique safety signal in Phase 3 studies, no dose adjustment is recommended. |
| efavirenz | ↓ | Efavirenz reduces plasma concentrations of raltegravir. The clinical significance of this interaction has not been directly assessed. |
| etravirine | ↓ | Etravirine reduces plasma concentrations of raltegravir. The clinical significance of this interaction has not been directly assessed. |
| tipranavir/ritonavir | ↓ | Tipranavir/ritonavir reduces plasma concentrations of raltegravir. However, since comparable efficacy was observed for this combination relative to other ISENTRESS-containing regimens in Phase 3 studies 018 and 019, no dose adjustment is recommended. |
| Other Agents | ||
| omeprazole | ↑ | Coadministration of medicinal products that increase gastric pH (e.g., omeprazole) may increase raltegravir levels based on increased raltegravir solubility at higher pH. However, since concomitant use of ISENTRESS with proton pump inhibitors and H2 blockers did not result in a unique safety signal in Phase 3 studies, no dose adjustment is recommended. |
| rifampin | ↓ | Rifampin, a strong inducer of UGT1A1, reduces plasma concentrations of raltegravir. The recommended dosage of ISENTRESS is 800 mg twice daily during coadministration with rifampin. |
Last updated on RxList: 7/21/2009
During the initial phase of treatment, patients responding to antiretroviral therapy may develop an inflammatory response to indolent or residual opportunistic infections (such as Mycobacterium avium complex, cytomegalovirus, Pneumocystis jirovecipneumonia, Mycobacterium tuberculosis, or reactivation of varicella zoster virus), which may necessitate further evaluation and treatment.
[See FDA-Approved Patient Labeling.]
Patients should be informed that ISENTRESS is not a cure for HIV infection or AIDS. They should also be told that people taking ISENTRESS may still get infections or other conditions common in people with HIV (opportunistic infections). Patients should also be told that it is very important that they stay under a physician's care during treatment with ISENTRESS.
Patients should be informed that ISENTRESS does not reduce the chance of passing HIV to others through sexual contact, sharing needles, or being exposed to blood. Patients should be advised to continue to practice safer sex and to use latex or polyurethane condoms or other barrier methods to lower the chance of sexual contact with any body fluids such as semen, vaginal secretions or blood. Patients should also be advised to never re-use or share needles.
Physicians should instruct their patients that if they miss a dose, they should take it as soon as they remember. If they do not remember until it is time for the next dose, they should be instructed to skip the missed dose and go back to the regular schedule. Patients should not take two tablets of ISENTRESS at the same time.
Physicians should instruct their patients to read the Patient Package Insert before starting ISENTRESS therapy and to reread each time the prescription is renewed. Patients should be instructed to inform their physician or pharmacist if they develop any unusual symptom, or if any known symptom persists or worsens.
Carcinogenicity studies of raltegravir in mice did not show any carcinogenic potential. At the highest dose levels, 400 mg/kg/day in females and 250 mg/kg/day in males, systemic exposure was 1.8-fold (females) or 1.2-fold (males) greater than the AUC (54 μM•hr) at the 400-mg twice daily human dose. Treatment-related squamous cell carcinoma of nose/nasopharynx was observed in female rats dosed with 600 mg/kg/day raltegravir for 104 weeks. These tumors were possibly the result of local irritation and inflammation due to local deposition and/or aspiration of drug in the mucosa of the nose/nasopharynx during dosing. No tumors of the nose/nasopharynx were observed in rats dosed with 150 mg/kg/day (males) and 50 mg/kg/day (females) and the systemic exposure in rats was 1.7-fold (males) to 1.4-fold (females) greater than the AUC (54 μM•hr) at the 400-mg twice daily human dose.
No evidence of mutagenicity or genotoxicity was observed in in vitro microbial mutagenesis (Ames) tests, in vitro alkaline elution assays for DNA breakage, and in vitro and in vivo chromosomal aberration studies.
No effect on fertility was seen in male and female rats at doses up to 600 mg/kg/day which resulted in a 3-fold exposure above the exposure at the recommended human dose.
ISENTRESS should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. There are no adequate and well-controlled studies in pregnant women. In addition, there have been no pharmacokinetic studies conducted in pregnant patients.
Developmental toxicity studies were performed in rabbits (at oral doses up to 1000 mg/kg/day) and rats (at oral doses up to 600 mg/kg/day). The reproductive toxicity study in rats was performed with pre-, peri-, and postnatal evaluation. The highest doses in these studies produced systemic exposures in these species approximately 3- to 4-fold the exposure at the recommended human dose. In both rabbits and rats, no treatment-related effects on embryonic/fetal survival or fetal weights were observed. In addition, no treatment-related external, visceral, or skeletal changes were observed in rabbits. However, treatment-related increases over controls in the incidence of supernumerary ribs were seen in rats at 600 mg/kg/day (exposures 3-fold the exposure at the recommended human dose).
Placenta transfer of drug was demonstrated in both rats and rabbits. At a maternal dose of 600 mg/kg/day in rats, mean drug concentrations in fetal plasma were approximately 1.5-to 2.5-fold greater than in maternal plasma at 1 hour and 24 hours postdose, respectively. Mean drug concentrations in fetal plasma were approximately 2% of the mean maternal concentration at both 1 and 24 hours postdose at a maternal dose of 1000 mg/kg/day in rabbits.
To monitor maternal-fetal outcomes of pregnant patients exposed to ISENTRESS, an Antiretroviral Pregnancy Registry has been established. Physicians are encouraged to register patients by calling 1800-258-4263.
Breast-feeding is not recommended while taking ISENTRESS. In addition, it is recommended that HIV-1-infected mothers not breast-feed their infants to avoid risking postnatal transmission of HIV-1.
It is not known whether raltegravir is secreted in human milk. However, raltegravir is secreted in the milk of lactating rats. Mean drug concentrations in milk were approximately 3-fold greater than those in maternal plasma at a maternal dose of 600 mg/kg/day in rats. There were no effects in rat offspring attributable to exposure of ISENTRESS through the milk.
Safety and effectiveness of ISENTRESS in pediatric patients have not been established.
Clinical studies of ISENTRESS did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. Other reported clinical experience has not identified differences in responses between the elderly and younger subjects. In general, dose selection for an elderly patient should be cautious, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.
No clinically important pharmacokinetic differences between subjects with moderate hepatic impairment and healthy subjects were observed. No dosage adjustment is necessary for patients with mild to moderate hepatic impairment. The effect of severe hepatic impairment on the pharmacokinetics of raltegravir has not been studied [see CLINICAL PHARMACOLOGY].
No clinically important pharmacokinetic differences between subjects with severe renal impairment and healthy subjects were observed. No dosage adjustment is necessary [see CLINICAL PHARMACOLOGY].
Last updated on RxList: 7/21/2009
No specific information is available on the treatment of overdosage with ISENTRESS. Doses as high as 1600-mg single dose and 800-mg twice-daily multiple doses were studied in healthy volunteers without evidence of toxicity. Occasional doses of up to 1800 mg per day were taken in the clinical studies of HIV1 infected subjects without evidence of toxicity.
In the event of an overdose, it is reasonable to employ the standard supportive measures, e.g., remove unabsorbed material from the gastrointestinal tract, employ clinical monitoring (including obtaining an electrocardiogram), and institute supportive therapy if required. The extent to which ISENTRESS may be dialyzable is unknown.
Raltegravir is an HIV-1 antiviral drug.
In a monotherapy study raltegravir (400 mg twice daily) demonstrated rapid antiviral activity with mean viral load reduction of 1.66 log10 copies/mL by Day 10.
In the randomized, double-blind, placebo-controlled, dose-ranging trial, Protocol 005, and Protocols 018 and 019, antiviral responses were similar among subjects regardless of dose.
In a randomized, placebo-controlled, crossover study, 31 healthy subjects were administered a single oral supratherapeutic dose of raltegravir 1600 mg and placebo. Peak raltegravir plasma concentrations were approximately 4-fold higher than the peak concentrations following a 400 mg dose. ISENTRESS did not appear to prolong the QTc interval for 12 hours postdose. After baseline and placebo adjustment, the maximum mean QTc change was -0.4 msec (1-sided 95% upper Cl: 3.1 msec).
Raltegravir is absorbed with a Tmax of approximately 3 hours postdose in the fasted state. Raltegravir AUC and Cmax increase dose proportionally over the dose range 100 mg to 1600 mg. Raltegravir C12hr increases dose proportionally over the dose range of 100 to 800 mg and increases slightly less than dose proportionally over the dose range 100 mg to 1600 mg. With twice-daily dosing, pharmacokinetic steady state is achieved within approximately the first 2 days of dosing. There is little to no accumulation in AUC and Cmax. The average accumulation ratio for C12hr ranged from approximately 1.2 to 1.6.
The absolute bioavailability of raltegravir has not been established.
In subjects who received 400 mg twice daily alone, raltegravir drug exposures were characterized by a geometric mean AUC0-12hr of 14.3 μM•hr and C12hr of 142 nM.
Considerable variability was observed in the pharmacokinetics of raltegravir. For observed C12hr in Protocols 018 and 019, the coefficient of variation (CV) for inter-subject variability = 212% and the CV for intra-subject variability = 122%.
ISENTRESS may be administered with or without food. Raltegravir was administered without regard to food in the pivotal safety and efficacy studies in HIV-1-infected patients. The effect of consumption of low-, moderate- and high-fat meals on steady-state raltegravir pharmacokinetics was assessed in healthy volunteers. Administration of multiple doses of raltegravir following a moderate-fat meal (600 Kcal, 21 g fat) did not affect raltegravir AUC to a clinically meaningful degree with an increase of 13% relative to fasting. Raltegravir C12hr was 66% higher and Cmax was 5% higher following a moderate-fat meal compared to fasting. Administration of raltegravir following a high-fat meal (825 Kcal, 52 g fat) increased AUC and Cmax by approximately 2-fold and increased C12hr by 4.1-fold. Administration of raltegravir following a low-fat meal (300 Kcal, 2.5 g fat) decreased AUC and Cmax by 46% and 52%, respectively; C12hr was essentially unchanged. Food appears to increase pharmacokinetic variability relative to fasting.
Raltegravir is approximately 83% bound to human plasma protein over the concentration range of 2 to 10 μM.
The apparent terminal half-life of raltegravir is approximately 9 hours, with a shorter α-phase half-life (~1 hour) accounting for much of the AUC. Following administration of an oral dose of radiolabeled raltegravir, approximately 51 and 32% of the dose was excreted in feces and urine, respectively. In feces, only raltegravir was present, most of which is likely derived from hydrolysis of raltegravir-glucuronide secreted in bile as observed in preclinical species. Two components, namely raltegravir and raltegravirglucuronide, were detected in urine and accounted for approximately 9 and 23% of the dose, respectively. The major circulating entity was raltegravir and represented approximately 70% of the total radioactivity; the remaining radioactivity in plasma was accounted for by raltegravir-glucuronide. Studies using isoform-selective chemical inhibitors and cDNA-expressed UDP-glucuronosyltransferases (UGT) show that UGT1A1 is the main enzyme responsible for the formation of raltegravir-glucuronide. Thus, the data indicate that the major mechanism of clearance of raltegravir in humans is UGT1A1-mediated glucuronidation.
The pharmacokinetics of raltegravir in pediatric patients has not been established.
The effect of age on the pharmacokinetics of raltegravir was evaluated in the composite analysis. No dosage adjustment is necessary.
The effect of race on the pharmacokinetics of raltegravir was evaluated in the composite analysis. No dosage adjustment is necessary.
A study of the pharmacokinetics of raltegravir was performed in healthy adult males and females. Additionally, the effect of gender was evaluated in a composite analysis of pharmacokinetic data from 103 healthy subjects and 28 HIV-1 infected subjects receiving raltegravir monotherapy with fasted administration. No dosage adjustment is necessary.
Raltegravir is eliminated primarily by glucuronidation in the liver. A study of the pharmacokinetics of raltegravir was performed in subjects with moderate hepatic impairment. Additionally, hepatic impairment was evaluated in the composite pharmacokinetic analysis. There were no clinically important pharmacokinetic differences between subjects with moderate hepatic impairment and healthy subjects. No dosage adjustment is necessary for patients with mild to moderate hepatic impairment. The effect of severe hepatic impairment on the pharmacokinetics of raltegravir has not been studied.
Renal clearance of unchanged drug is a minor pathway of elimination. A study of the pharmacokinetics of raltegravir was performed in subjects with severe renal impairment. Additionally, renal impairment was evaluated in the composite pharmacokinetic analysis. There were no clinically important pharmacokinetic differences between subjects with severe renal impairment and healthy subjects. No dosage adjustment is necessary. Because the extent to which ISENTRESS may be dialyzable is unknown, dosing before a dialysis session should be avoided.
There is no evidence that common UGT1A1 polymorphisms alter raltegravir pharmacokinetics to a clinically meaningful extent. In a comparison of 30 subjects with *28/*28 genotype (associated with reduced activity of UGT1A1) to 27 subjects with wild-type genotype, the geometric mean ratio (90% CI) of AUC was 1.41 (0.96, 2.09). Drug Interactions [see DRUG INTERACTIONS]
Table 7: Effect of Other Agents on the Pharmacokinetics of
Raltegravir
| Coadministered Drug |
Coadministered Drug Dose/Schedule |
Raltegravir Dose/Schedule |
Ratio (90% Confidence Interval) of Raltegravir
Pharmacokinetic Parameters with/without Coadministered Drug; No Effect= 1.00 |
|||
| n | Cmax | AUC | Cmin | |||
| atazanavir | 400 mg daily | 100 mg single dose | 10 | 1.53 | 1.72 | 1.95 |
| (1.11,2.12) | (1.47,2.02) | (1.30,2.92) | ||||
| atazanavir/ritonavir | 300 mg/100 mg daily | 400 mg twice daily | 10 | 1.24 | 1.41 | 1.77 |
| (0.87,1.77) | (1.12,1.78) | (1.39,2.25) | ||||
| efavirenz | 600 mg daily | 400 mg single dose | 9 | 0.64 | 0.64 | 0.79 |
| (0.41,0.98) | (0.52,0.80) | (0.49,1.28) | ||||
| etravirine | 200 mg twice daily | 400 mg twice daily | 19 | 0.89 | 0.90 | 0.66 |
| (0.68,1.15) | (0.68,1.18) | (0.34,1.26) | ||||
| omeprazole | 20 mg daily | 400 mg single dose | 14 (10 for AUC) | 4.15 | 3.12 | 1.46 |
| (2.82,6.10) | (2.13,4.56) | (1.10,1.93) | ||||
| rifampin | 600 mg daily | 400 mg single dose | 9 | 0.62 | 0.60 | 0.39 |
| (0.37,1.04) | (0.39,0.91) | (0.30,0.51) | ||||
| rifampin | 600 mg daily | 400 mg twice daily when administered alone; 800 mg twice daily when administered with rifampin | 14 | 1.62 | 1.27 | 0.47 |
| (1.12,2.33) | (0.94,1.71) | (0.36,0.61) | ||||
| ritonavir | 100 mg twice daily | 400 mg single dose | 10 | 0.76 | 0.84 | 0.99 |
| (0.55,1.04) | (0.70,1.01) | (0.70,1.40) | ||||
| tenofovir | 300 mg daily | 400 mg twice daily | 9 | 1.64 | 1.49 | 1.03 |
| (1.16,2.32) | (1.15,1.94) | (0.73,1.45) | ||||
| tipranavir/ritonavir | 500 mg/200 mg twice daily | 400 mg twice daily | 15 (14 for Cmin) | 0.82 | 0.76 | 0.45 |
| (0.46,1.46) | (0.49,1.19) | (0.31,0.66) | ||||
Raltegravir inhibits the catalytic activity of HIV-1 integrase, an HIV-1 encoded enzyme that is required for viral replication. Inhibition of integrase prevents the covalent insertion, or integration, of unintegrated linear HIV-1 DNA into the host cell genome preventing the formation of the HIV-1 provirus. The provirus is required to direct the production of progeny virus, so inhibiting integration prevents propagation of the viral infection. Raltegravir did not significantly inhibit human phosphoryltransferases including DNA polymerases α, β, and γ.
Raltegravir at concentrations of 31 ± 20 nM resulted in 95% inhibition (EC95) of viral spread (relative to an untreated virus-infected culture) in human T-lymphoid cell cultures infected with the cell-line adapted HIV-1 variant H9IIIB. In addition, 5 clinical isolates of HIV-1 subtype B had EC95 values ranging from 9 to 19 nM in cultures of mitogen-activated human peripheral blood mononuclear cells. In a single-cycle infection assay, raltegravir inhibited infection of 23 HIV-1 isolates representing 5 non-B subtypes (A, C, D, F, and G) and 5 circulating recombinant forms (AE, AG, BF, BG, and cpx) with EC50 values ranging from 5 to 12 nM. Raltegravir also inhibited replication of an HIV-2 isolate when tested in CEMx174 cells (EC95 value = 6 nM). Additive to synergistic antiretroviral activity was observed when human T-lymphoid cells infected with the H9IIIB variant of HIV-1 were incubated with raltegravir in combination with non-nucleoside reverse transcriptase inhibitors (delavirdine, efavirenz, or nevirapine); nucleoside analog reverse transcriptase inhibitors (abacavir, didanosine, lamivudine, stavudine, tenofovir, zalcitabine, or zidovudine); protease inhibitors (amprenavir, atazanavir, indinavir, lopinavir, nelfinavir, ritonavir, or saquinavir); or the entry inhibitor enfuvirtide.
The mutations observed in the HIV-1 integrase coding sequence that contributed to raltegravir resistance (evolved either in cell culture or in subjects treated with raltegravir) generally included an amino acid substitution at either Q148 (changed to H, K, or R) or N155 (changed to H) plus one or more additional substitutions (i.e., L74M, E92Q, T97A, E138A/K, G140A/S, V151I, G163R, H183P, Y226C/D/F/H, S230R and D232N). Amino acid substitution at Y143C/H/R is another pathway to raltegravir resistance.
Treatment-Naļve Subjects: By Week 48 in the STARTMRK trial, the primary raltegravir resistance-associated substitutions were observed in 3 (1 with Y143R and 2 with Q148H/R) of the 6 virologic failure subjects with evaluable paired genotypic data.
Treatment-Experienced Subjects: By Week 48 in the BENCHMRK trials, at least one of the 3 primary raltegravir resistance-associated substitutions, Y143C/H/R, Q148H/K/R, and N155H, was observed in 63 (64.3%) of the 98 virologic failure subjects with evaluable genotypic data from paired baseline and raltegravir treatment-failure isolates. Some (n=18) of those HIV-1 isolates harboring one or more of the 3 primary raltegravir resistance-associated substitutions were evaluated for raltegravir susceptibility yielding a median decrease of 47.3-fold (mean 73.1 ± 60.8-fold decrease, ranging from 0.9- to 200-fold) compared to baseline isolates.
The evidence of durable efficacy of ISENTRESS is based on the analyses of 48-week data from an ongoing, randomized, double-blind, active-control trial, STARTMRK (Protocol 021) in antiretroviral treatment-naive HIV-1 infected adult subjects and from 2 ongoing, randomized, double-blind, placebo-controlled studies, BENCHMRK 1 and BENCHMRK 2 (Protocols 018 and 019), in antiretroviral treatment-experienced HIV-1 infected adult subjects. These efficacy results were supported by the 96-week analysis of a randomized, double-blind, controlled, dose-ranging trial, Protocol 004, in antiretroviral treatment-naļve HIV-1 infected adult subjects and by the 48-week analysis of a randomized, double-blind, controlled, dose-ranging study, Protocol 005, in antiretroviral treatment-experienced HIV-1 infected adult subjects.
STARTMRK (Protocol 021) is a Phase 3 study to evaluate the safety and antiretroviral activity of ISENTRESS 400 mg twice daily + emtricitabine (+) tenofovir versus efavirenz 600 mg at bedtime plus emtricitabine (+) tenofovir in treatment-naļve HIV-1-infected subjects with HIV-1 RNA > 5000 copies/mL. Randomization was stratified by screening HIV-1 RNA level ( ≤ 50,000 copies/mL; and > 50,000 copies/mL) and by hepatitis status.
Table 8 shows the demographic characteristics of subjects in the group receiving ISENTRESS 400 mg twice daily and subjects in the comparator group.
Table 8: Baseline Characteristics
| Randomized Study Protocol 021 | ISENTRESS 400 mg Twice Daily (N = 281) |
Efavirenz 600 mg At Bedtime (N = 282) |
| Gender | ||
| Male | 81% | 82% |
| Female | 19% | 18% |
| Race | ||
| White | 41% | 44% |
| Black | 12% | 8% |
| Asian | 13% | 11% |
| Hispanic | 21% | 24% |
| Native American | 0% | 0% |
| Multiracial | 12% | 13% |
| Region | ||
| Latin America | 35% | 34% |
| Southeast Asia | 12% | 10% |
| North America | 29% | 32% |
| EU/Australia | 23% | 23% |
| Age (years) | ||
| 18-64 | 99% | 99% |
| ≥ 65 | 1% | 1% |
| Mean (SD) | 38 (9) | 37 (10) |
| Median (min, max) | 37 (19 to 67) | 36 (19 to 71) |
| CD4 Cell Count (cells/microL) | ||
| Mean (SD) | 219 (124) | 217 (134) |
| Median (min, max) | 212 (1 to 620) | 204 (4 to 807) |
| Plasma HIV-1 RNA (log10 copies/mL) | ||
| Mean (SD) | 5 (1) | 5 (1) |
| Median (min, max) | 5 (3 to 6) | 5 (4 to 6) |
| Plasma HIV-1 RNA (copies/mL) | ||
| Geometric Mean | 103205 | 106215 |
| Median (min, max) | 114000 (400 to 750000) | 104000 (4410 to 750000) |
| History of AIDS† | ||
| Yes | 18% | 21% |
| Viral Subtype | ||
| Clade B | 78% | 82% |
| Non-Clade B‡ | 21% | 17% |
| Baseline Plasma HIV-1 RNA | ||
| ≤ 100,000 copies/mL | 45% | 49% |
| > 100,000 copies/mL | 55% | 51% |
| Baseline CD4 Cell Counts | ||
| ≤ 50 cells/mm³ | 10% | 11% |
| > 50 cells/mm³ and ≤ 200 cells/mm³ | 37% | 37% |
| > 200 cells/mm³ | 53% | 51% |
| Hepatitis Status | ||
| Hepatitis B or C Positive§ | 6% | 6% |
| †Includes additional subjects identified as having
a history of AIDS. ‡Non-Clade B Subtypes (# of subjects): Clade A (4), A/C (1), A/G (2), A1 (1), AE (29), AG (12), BF (6), C (37), D (2), F (2), F1 (5), G (2), Complex (3). §Evidence of hepatitis B surface antigen or evidence of HCV RNA by polymerase chain reaction (PCR) quantitative test for hepatitis C Virus. Notes: ISENTRESS and Efavirenz were administered with emtricitabine (+) tenofovir N = Number of subjects in each group. |
||
Week 48 outcomes from Protocol 021 are shown in Table 9.
Table 9: Outcomes by Treatment Group through Week 48
| Randomized Study Protocol 021 | ISENTRESS 400 mg Twice Daily (N = 281) |
Efavirenz 600 mg At Bedtime (N = 282) |
Difference (ISENTRESS Efavirenz) (CI§) |
| Outcome at Week 48 | |||
| Subjects with HIV-1 RNA less than 50 copies/mL | 87% | 82% | 4.7% (-1.3%, 10.6%) |
| Subjects with HIV-1 RNA less than 400 copies/mL | 91% | 88% | 3.6% (-1.5%, 8.7%) |
| Mean CD4 cell count change from baseline (cells/mm³) | 176 | 150 | 25.8 (5.0, 46.5) |
| Virologic Failure (>50 copies/mL) | 6% | 7% | |
| Never suppressed through Week 48 and on study at Week 48 | 2% | 3% | |
| Rebound | 5% | 5% | |
| Discontinued study drug | 7% | 10% | |
| Reasons for Discontinuation | |||
| Death | < 1% | 0% | |
| Adverse experiences | 2% | 5% | |
| Other* | 4% | 5% | |
| § The 95% CI for treatment difference is adjusted by
the screening HIV RNA level ( < =50,000 copies/mL vs. > 50,000 copies/mL)
and Hepatitis B or C (negative vs. positive) *Other includes lack of efficacy, loss to follow-up, consent withdrawn, protocol violation and other |
|||
BENCHMRK 1 and BENCHMRK 2 are Phase 3 studies to evaluate the safety and antiretroviral activity of ISENTRESS 400 mg twice daily in combination with an optimized background therapy (OBT), versus OBT alone, in HIV-1-infected subjects, 16 years or older, with documented resistance to at least 1 drug in each of 3 classes (NNRTIs, NRTIs, PIs) of antiretroviral therapies. Randomization was stratified by degree of resistance to PI (1PI vs. > 1PI) and the use of enfuvirtide in the OBT. Prior to randomization, OBT was selected by the investigator based on genotypic/phenotypic resistance testing and prior ART history.
Table 10 shows the demographic characteristics of subjects in the group receiving ISENTRESS 400 mg twice daily and subjects in the placebo group.
Table 10: Baseline Characteristics
| Randomized Studies Protocol 018 and 019 | ISENTRESS 400 mg Twice Daily+ OBT (N = 462) |
Placebo+ OBT (N = 237) |
| Gender | ||
| Male | 88% | 89% |
| Female | 12% | 11% |
| Race | ||
| White | 65% | 73% |
| Black | 14% | 11% |
| Asian | 3% | 3% |
| Hispanic | 11% | 8% |
| Others | 6% | 5% |
| Age (years) | ||
| Median (min, max) | 45 (16 to 74) | 45 (17 to 70) |
| CD4+ Cell Count | ||
| Median (min, max), cells/mm³ | 119 (1 to 792) | 123 (0 to 759) |
| ≤ 50 cells/mm³ | 32% | 33% |
| > 50 and ≤ 200 cells/mm³ | 37% | 36% |
| Plasma HIV-1 RNA | ||
| Median (min, max), log10 copies/mL | 4.8 (2 to 6) | 4.7 (2 to 6) |
| > 100,000 copies/mL | 35% | 33% |
| History of AIDS | ||
| Yes | 92% | 91% |
| Prior Use of ART, Median (1st Quartile, 3rd Quartile) | ||
| Years of ART Use | 10 (7 to 12) | 10 (8 to 12) |
| Number of ART | 12 (9 to 15) | 12 (9 to 14) |
| Hepatitis Co-infection* | ||
| No Hepatitis B or C virus | 83% | 85% |
| Hepatitis B virus only | 8% | 3% |
| Hepatitis C virus only | 8% | 11% |
| Co-infection of Hepatitis B and C virus | 1% | 1% |
| Stratum | ||
| Enfuvirtide in OBT | 38% | 38% |
| Resistant to ≥ 2 PI | 97% | 95% |
| *Hepatitis B virus surface antigen positive or hepatitis C virus antibody positive. | ||
Table 11 compares the characteristics of optimized background therapy at baseline in the group receiving ISENTRESS 400 mg twice daily and subjects in the control group.
Table 11: Characteristics of Optimized Background Therapy
at Baseline
| Randomized Studies Protocol 018 and 019 | ISENTRESS 400 mg Twice Daily + OBT (N = 462) |
Placebo + OBT (N = 237) |
| Number of ARTs in OBT | ||
| Median (min, max) | 4 (1 to 7) | 4 (2 to 7) |
| Number of Active PI in OBT by Phenotypic Resistance Test* | ||
| 0 | 36% | 41% |
| 1 or more | 60% | 58% |
| Phenotypic Sensitivity Score (PSS)† | ||
| 0 | 15% | 19% |
| 1 | 31% | 30% |
| 2 | 31% | 28% |
| 3 or more | 18% | 20% |
| Genotypic Sensitivity Score (GSS)† | ||
| 0 | 25% | 28% |
| 1 | 39% | 41% |
| 2 | 24% | 21% |
| 3 or more | 11% | 10% |
| *Darunavir use in OBT in darunavir naļve subjects was counted
as one active PI. †The Phenotypic Sensitivity Score (PSS) and the Genotypic Sensitivity Score (GSS) were defined as the total oral ARTs in OBT to which a subject's viral isolate showed phenotypic sensitivity and genotypic sensitivity, respectively, based upon phenotypic and genotypic resistance tests. Enfuvirtide use in OBT in enfuvirtidenaļve subjects was counted as one active drug in OBT in the GSS and PSS. Similarly, darunavir use in OBT in darunavir-naļve subjects was counted as one active drug in OBT. |
||
Week 48 outcomes for the 699 subjects randomized and treated with the recommended dose of ISENTRESS 400 mg twice daily or placebo in the pooled BENCHMRK 1 and 2 studies are shown in Table 12.
Table 12: Outcomes by Treatment Group through Week 48
| Randomized Studies Protocol 018 and 019 | ISENTRESS 400mg Twice Daily + OBT (N = 462) |
Placebo+ OBT (N = 237) |
| Outcome at Week 48 | ||
| Subjects with HIV-1 RNA less than 400 copies/mL | 72% | 37% |
| Subjects with HIV-1 RNA less than 50 copies/mL | 60% | 31% |
| Mean CD4 cell count change from baseline (cells/mm³) | 106 | 44 |
| Virologic Failure ( > 50 copies/mL) | 36% | 65% |
| Never suppressed through Week 48 and on study at Week 48 | 11% | 9% |
| Rebound | 13% | 8% |
| Non-responder by Week 48‡ | 12% | 48% |
| Discontinued study drug | 4% | 4% |
| Reasons for Discontinuation | ||
| Death | 2% | 2% |
| Adverse Experiences | < 1% | < 1% |
| Other* | 2% | 1% |
| ‡ The non-responders by Week 48 were defined by the protocol
as those who did not achieve > 1.0 log10 HIV-1 RNA reduction
and < 400 HIV-1 RNA copies/mL starting at Week 16 or beyond. *Other includes lack of efficacy, loss to follow-up, consent withdrawn |
||
The mean changes in plasma HIV-1 RNA from baseline were -2.11 log10 copies/mL in the group receiving ISENTRESS 400 mg twice daily and -0.96 log10 copies/mL for the control group.
Treatment-emergent CDC Category C events occurred in 4% of the group receiving ISENTRESS 400 mg twice daily and 5% of the control group.
Virologic responses at Week 48 by baseline genotypic and phenotypic sensitivity score are shown in Table 13.
Table 13: Virologic Response at Week 48 by Baseline Genotypic/Phenotypic
Sensitivity Score
| Randomized Studies Protocol 018 and 019 | Percent with HIV-1RNA < 400copies/mL at Week 48 |
Percent with HIV-1 RNA < 50 copies/mL at Week 48 |
||||||
| n | ISENTRESS 400 mg Twice Daily + OBT (N = 462) |
n | Placebo + OBT (N = 237) |
n | ISENTRESS 400 mg Twice Daily + OBT (N = 462) |
n | Placebo + OBT (N = 237) |
|
| Phenotypic Sensitivity Score (PSS)* | ||||||||
| 0 | 69 | 52 | 44 | 5 | 69 | 46 | 44 | 2 |
| 1 | 145 | 72 | 72 | 32 | 145 | 57 | 72 | 28 |
| 2 | 142 | 83 | 66 | 42 | 142 | 68 | 66 | 38 |
| 3 or more | 85 | 72 | 48 | 60 | 85 | 67 | 48 | 46 |
| Genotypic Sensitivity Score (GSS)* | ||||||||
| 0 | 115 | 50 | 66 | 8 | 115 | 43 | 66 | 3 |
| 1 | 178 | 79 | 96 | 38 | 178 | 63 | 96 | 35 |
| 2 | 111 | 85 | 49 | 65 | 111 | 70 | 49 | 53 |
| 3 or more | 51 | 69 | 23 | 52 | 51 | 67 | 23 | 39 |
| *The Phenotypic Sensitivity Score (PSS) and the Genotypic Sensitivity Score (GSS) were defined as the total oral ARTs in OBT to which a subject's viral isolate showed phenotypic sensitivity and genotypic sensitivity, respectively, based upon phenotypic and genotypic resistance tests. Enfuvirtide use in OBT in enfuvirtide-naļve subjects was counted as one active drug in OBT in the GSS and PSS. Similarly, darunavir use in OBT in darunavir-naļve subjects was counted as one active drug in OBT. | ||||||||
Last updated on RxList: 7/21/2009
ISENTRESS®
(eye sen tris) (raltegravir) Tablets
Read the patient information that comes with ISENTRESS1 before you start taking it and each time you get a refill. There may be new information. This leaflet is a summary of the information for patients. Your doctor or pharmacist can give you additional information. This leaflet does not take the place of talking with your doctor about your medical condition or your treatment.
What is ISENTRESS?
ISENTRESS must be used with other anti-HIV medicines.
How does ISENTRESS work?
Does ISENTRESS lower the chance of passing HIV to other people?
No. ISENTRESS does not reduce the chance of passing HIV to others through sexual contact, sharing needles, or being exposed to your blood.
Ask your doctor if you have any questions about safer sex or how to prevent passing HIV to other people.
What should I tell my doctor before and during treatment with ISENTRESS?
Tell your doctor about all of your medical conditions. Include any of the following that applies to you:
Tell your doctor about all the medicines you take. Include the following:
Know the medicines you take.
How should I take ISENTRESS?
Take ISENTRESS exactly as your doctor has prescribed. The recommended dose is as follows:
Do not change your dose or stop taking ISENTRESS or your other anti-HIV medicines without first talking with your doctor.
IMPORTANT: Take ISENTRESS exactly as your doctor prescribed and at the right times of day because if you don't:
If you fail to take ISENTRESS the way you should, here's what to do:
Be sure to keep a supply of your anti-HIV medicines.
What are the possible side effects of ISENTRESS?
When ISENTRESS has been given with other anti-HIV drugs, the most common side effects included:
Other side effects include rash, severe skin reactions, feeling anxious, depression, suicidal thoughts and actions, paranoia.
A condition called Immune Reconstitution Syndrome can happen in some patients with advanced HIV infection (AIDS) when combination antiretroviral treatment is started. Signs and symptoms of inflammation from opportunistic infections that a person has or had may occur as the medicines work to treat the HIV infection and help to strengthen the immune system. Call your doctor right away if you notice any signs or symptoms of an infection after starting ISENTRESS with other anti-HIV medicines.
Contact your doctor promptly if you experience unexplained muscle pain, tenderness, or weakness while taking ISENTRESS. This is because on rare occasions, muscle problems can be serious and can lead to kidney damage.
Tell your doctor if you have any side effects that bother you.
These are not all the side effects of ISENTRESS. For more information, ask your doctor or pharmacist.
How should I store ISENTRESS?
General information about the use of ISENTRESS
Medicines are sometimes prescribed for conditions that are not mentioned in patient information leaflets.
This leaflet gives you the most important information about ISENTRESS.
What are the ingredients in ISENTRESS?
Active ingredient: Each film-coated tablet contains 400 mg of raltegravir.
Inactive ingredients: Microcrystalline cellulose, lactose monohydrate, calcium phosphate dibasic anhydrous, hypromellose 2208, poloxamer 407 (contains 0.01% butylated hydroxytoluene as antioxidant), sodium stearyl fumarate, magnesium stearate. In addition, the film coating contains the following inactive ingredients: polyvinyl alcohol, titanium dioxide, polyethylene glycol 3350, talc, red iron oxide and black iron oxide.
Last updated on RxList: 7/21/2009
IMPORTANT NOTE: This is a summary and does not contain all possible information about this product. For complete information about this product or your specific health needs, ask your health care professional. Always seek the advice of your health care professional if you have any questions about this product or your medical condition. This information is not intended as individual medical advice and does not substitute for the knowledge and judgment of your health care professional. This information does not contain any assurances that this product is safe, effective, or appropriate for you.
RALTEGRAVIR - ORAL
(RAL-te-GRA-vir)
COMMON BRAND NAME(S): Isentress
USES: Raltegravir is used with other medications to help control your HIV infection, thereby improving your quality of life. It also lowers your risk of getting complications from HIV (e.g., new infections, cancer). This medication is usually prescribed to people who have taken other HIV medications that did not work well enough to control their HIV. Raltegravir is known as an integrase inhibitor. It blocks the virus from growing and infecting more cells.
Raltegravir is not a cure for HIV, and it does not prevent the spread of HIV to others through sexual contact or blood contamination (e.g., sharing used needles).
HOW TO USE: Read the Patient Information Leaflet provided by your pharmacist before you start using raltegravir and each time you get a refill. If you have any questions, consult your doctor or pharmacist.
Take this medication by mouth with or without food, usually 2 times daily or as directed by your doctor.
It is very important to continue taking this medication (and other HIV medications) exactly as prescribed by your doctor.
Do not increase your dose or take this medication more often than prescribed. Your condition will not improve any faster, and the risk of serious side effects may be increased.
Do not take less of this drug than prescribed or stop taking it (or other HIV medicines) even for a short time unless directed to do so by your doctor. Doing so may cause the amount of virus to increase and/or make the infection more difficult to treat (resistant).
This medication works best when the amount of drug in your body is kept at a constant level. Therefore, take this drug at evenly spaced intervals. To help you remember, take it at the same times each day.
Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
Tell your doctor immediately if any of these unlikely but serious side effects occur: unusual tiredness/weakness, changes in body fat (e.g., increased fat in upper back), change in the amount of urine, persistent nausea/vomiting, severe stomach/abdominal pain, dark urine, yellowing eyes/skin, muscle pain/tenderness/weakness.
Seek immediate medical attention if any of these rare but very serious side effects occur: chest/jaw/left arm pain.
When you first start this medication (or other HIV medications), you may experience symptoms of an old infection. This may happen as your immune system begins to work better. Contact your doctor immediately if you notice any of the following symptoms: new cough, trouble breathing, signs of infection (e.g., fever), new vision problems, new headaches, new skin problems.
A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the tongue/lips/throat), severe dizziness, trouble breathing.
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.
Contact your doctor for medical advice about side effects. The following numbers do not provide medical advice, but in the US you may report side effects to the Food and Drug Administration (FDA) at 1-800-FDA-1088. In Canada, you may call Health Canada at 1-866-234-2345.
PRECAUTIONS: Before taking raltegravir, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies.
Before using this medication, tell your doctor or pharmacist your medical history, especially of: liver disease (e.g., hepatitis B, hepatitis C).
During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.
It is not known if this medication passes into breast milk. Because breast milk can transmit HIV, do not breast-feed.
Before using this medication, tell your doctor or pharmacist of all prescription and nonprescription/herbal products you may use, especially of: drugs affecting liver enzymes that remove raltegravir from your body (such as rifampin).
This document does not contain all possible interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist.
OVERDOSE: If overdose is suspected, contact your local poison control center or emergency room immediately. US residents can call the US National Poison Hotline at 1-800-222-1222. Canada residents can call a provincial poison control center.
NOTES: To reduce the risk of spreading HIV to others, always use effective barrier protections (e.g., latex or polyurethane condoms, dental dams) during all sexual activity. Consult your doctor or pharmacist for more details.
Do not share this medication with others.
Laboratory and/or medical tests (e.g., viral load, T-cell counts) should be performed periodically to monitor your progress or check for side effects. Consult your doctor for more details.
Keep all medical and laboratory appointments.
MISSED DOSE: If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.
STORAGE: Store at room temperature between 68-77 degrees F (20-25 degrees C) away from light and moisture. Brief storage between 59-86 degrees F (15-30 degrees C) is permitted. Do not store in the bathroom. Keep all medicines away from children and pets.
Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company for more details about how to safely discard your product.
MEDICAL ALERT: Your condition can cause complications in a medical emergency. For information about enrolling in MedicAlert, call 1-800-854-1166 (USA) or 1-800-668-1507 (Canada).
Information last revised July 2008 Copyright(c) 2008 First DataBank, Inc.
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