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Side Effects > Fuzeon

Fuzeon Side Effects

Generic Name: enfuvirtide

Please note - some side effects for Fuzeon may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA at http://www.fda.gov/medwatch/ or 1-800-FDA-1088 (1-800-332-1088).


Side Effects of Fuzeon - for the Consumer

Fuzeon

All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome when using Fuzeon:

Constipation; diarrhea; dizziness; injection site reactions (pain, redness, itching, bleeding, bruising, hardened skin, or bumps); loss of appetite; muscle pain; nausea; tiredness; trouble sleeping; weakness.

Seek medical attention right away if any of these SEVERE side effects occur when using Fuzeon:

Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); anxiety; blood in the urine; depression; fever with vomiting and skin rash; flu-like symptoms; severe of persistent stomach pain; signs of infection at the injection site (eg, oozing, swelling, increasing heat); signs of pneumonia (eg, cough with fever, rapid breathing, shortness of breath); stomach pain; swelling of the feet.

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Fuzeon Side Effects - for the Professional

Fuzeon Injection

The overall safety profile of Fuzeon is based on 2131 subjects who received at least 1 dose of Fuzeon during various clinical trials. This includes 2051 adults, 658 of whom received the recommended dose for greater than 48 weeks, and 63 pediatric subjects.

Assessment of treatment-emergent adverse events is based on the pooled data from the two Phase 3 studies T20-301 and T20-302.

Local Injection Site Reactions

Local injection site reactions were the most frequent adverse events associated with the use of Fuzeon. In Phase 3 clinical studies (T20-301 and T20-302), 98% of subjects had at least one local injection site reaction (ISR). A total of 7% of subjects discontinued treatment with Fuzeon because of ISRs (4%) or difficulties with injecting Fuzeon (3%) such as injection fatigue and inconvenience. Eighty-five percent of subjects experienced their first ISR during the initial week of treatment; ISRs continued to occur throughout treatment with Fuzeon. For most subjects the severity of signs and symptoms associated with ISRs did not change during the 48 weeks of treatment. The majority of ISRs were associated with erythema, induration, the presence of nodules or cysts, and mild to moderate pain at the injection site (Table 4). In addition, the average duration of individual ISRs was between three and seven days in 41% of subjects and more than seven days in 24% of subjects. Also, the numbers of ISRs per subject at any one time was between six to 14 ISRs in 26% of subjects and more than 14 ISRs in 1.3% of subjects. Infection at the injection site (including abscess and cellulitis) was reported in 1.7% of adult subjects.

Table 4Summary of Individual Signs/Symptoms Characterizing Local Injection Site Reactions to Enfuvirtide in Studies T20-301 and T20-302 Combined (% of Subjects) Through 48 Weeks
N=663
Event Category Any Severity Grade % of Patients with Grade 3 Reactions % of Patients with Grade 4 Reactions
*
Grade 3 = severe pain requiring prescription non-topical analgesics or limiting usual activities.
Grade 4 = severe pain requiring hospitalization or prolongation of hospitalization, resulting in death, or persistent or significant disability/incapacity, or life-threatening, or medically significant.
Grade 3 = refractory to topical treatment or requiring oral or parenteral treatment; Grade 4 = not applicable.
Pain/Discomfort * 96% 11%     0%    
Induration 90% 39%     18%    
>25 but <50 mm     ≥50 mm    
Erythema 91% 22%     10%    
>50 but <85 mm     ≥85 mm    
Nodules and Cysts 80% 23%     0.2%    
>3 cm average     diameter     draining    
Pruritus 65% 3%     NA    
Ecchymosis 52% 5%     2%    
>3 but ≤5 cm     >5 cm    
Biojector 2000 Needle-Free Device

Adverse events associated with the use of the Biojector 2000 needle-free device for administration of Fuzeon have included: nerve pain (neuralgia and/or paresthesia) lasting up to 6 months associated with administration at anatomical sites where large nerves course close to the skin, bruising and hematomas.

Other Adverse Events

Systemic hypersensitivity reactions have been attributed to Fuzeon (≤1%) and in some cases have recurred upon re-challenge.

In the T20-301 and T20-302 studies, after study week 8, patients on background alone who met protocol defined criteria for virological failure were permitted to revise their background regimens and add Fuzeon. Exposure on Fuzeon+background was 557 patient-years, and to background alone 162 patient-years. Due to this difference in exposure, safety results are expressed as the number of patients with an adverse event per 100 patient-years of exposure. For Fuzeon+background, adverse events are also displayed by percent of subjects.

The events most frequently reported in subjects receiving Fuzeon+background regimen, excluding injection site reactions, were diarrhea (38 per 100 patient-years or 31.7%), nausea (27 per 100 patient-years or 22.8%), and fatigue (24 per 100 patient-years or 20.2%). These events were also commonly observed in subjects that received background regimen alone: diarrhea (73 per 100 patient-years), nausea (50 per 100 patient-years), and fatigue (38 per 100 patient-years).

Treatment-emergent adverse events, regardless of causality and excluding ISRs, from Phase 3 studies are summarized for adult subjects, in Table 5. Any Grade 2 or above events occurring at ≥2 percent of subjects and at a higher rate in subjects treated with Fuzeon are summarized in Table 5; events that occurred at a higher rate in the control arms are not displayed.

Rates of adverse events for patients who switched to Fuzeon after virological failure were similar.

Table 5Rates of Treatment-Emergent Adverse Events* (≥Grade 2) Reported in ≥2 % of Patients Treated with Fuzeon (Pooled Studies T20-301/T20-302 at 48 Weeks)
Adverse Event (by System Organ Class) Fuzeon+Background Regimen
(N=663)
Fuzeon+Background Regimen
(N=663)
Background Regimen
(N=334)
*
Excludes Injection Site Reactions
Events listed occurred more frequently in patients treated with Fuzeon (based on rates/100 patient-years).
663 patients total 557 total patient-years 162 total patient-years
% frequency rate/100 patient-years rate/100 patient-years
Weight Decreased 6.6% 7.9 6.2
Sinusitis 6.0% 7.2 4.9
Abdominal Pain 3.9% 4.7 3.7
Cough 3.9% 4.7 2.5
Herpes Simplex 3.5% 4.1 3.7
Appetite Decreased 3.2% 3.8 2.5
Pancreatitis 3.0% 3.6 2.5
Pain in Limb 2.9% 3.4 3.1
Pneumonia 2.7% 3.2 0.6
Myalgia 2.7% 3.2 1.2
Influenza-Like Illness 2.4% 2.9 1.9
Folliculitis 2.4% 2.9 2.5
Anorexia 2.3% 2.7 1.9
Dry Mouth 2.1% 2.5 1.9
Conjunctivitis 2.0% 2.3 1.9

The incidence of pneumonia was 2.7% or 3.2 events/100 patient-years in subjects receiving Fuzeon+background regimen. On analysis of all diagnoses of pneumonia (pneumonia, bacterial pneumonia, bronchopneumonia, and related terms) in the Phase 3 clinical trials, an increased rate of bacterial pneumonia was observed in subjects treated with Fuzeon compared to the control arm (6.9%, 6.7 pneumonia events per 100 patient-years versus 0.6 events per 100 patient-years, respectively). Approximately half of the study subjects with pneumonia required hospitalization. Three subject deaths in the Fuzeon arm were attributed to pneumonia; all three had serious concomitant AIDS-related illnesses that contributed to their deaths. Risk factors for pneumonia included low initial CD4+ lymphocyte count, high initial viral load, intravenous drug use, smoking, and a prior history of lung disease. It is unclear if the increased incidence of pneumonia was related to Fuzeon use. However, because of this finding, patients with HIV infection should be carefully monitored for signs and symptoms of pneumonia, especially if they have underlying conditions which may predispose them to pneumonia.

Less Common Events

The following adverse events have been reported in 1 or more subjects; however, a causal relationship to Fuzeon has not been established.

Immune System Disorders: worsening abacavir hypersensitivity reaction

Renal and Urinary Disorders: glomerulonephritis; tubular necrosis; renal insufficiency; renal failure (including fatal cases)

Blood and Lymphatic Disorders: thrombocytopenia; neutropenia; fever; lymphadenopathy

Endocrine and Metabolic: hyperglycemia

Infections: sepsis; herpes simplex

Nervous System Disorders: taste disturbance; Guillain-Barre syndrome (fatal); sixth nerve palsy; peripheral neuropathy

Cardiac Disorders: unstable angina pectoris

Gastrointestinal Disorders: constipation; abdominal pain upper

General: asthenia

Hepatobiliary Disorders: toxic hepatitis; hepatic steatosis

Investigations: increased amylase; increased lipase; increased AST; increased GGT; increased triglycerides

Psychiatric Disorders: insomnia; depression; anxiety; suicide attempt

Respiratory, Thoracic, and Mediastinal Disorders: pneumopathy; respiratory distress; cough

Skin and Subcutaneous Tissue Disorders: pruritus

Laboratory Abnormalities

Table 6 shows the treatment-emergent laboratory abnormalities that occurred in at least 2 subjects per 100 patient-years and more frequently in those receiving Fuzeon+background regimen than background regimen alone from studies T20-301 and T20-302.

Table 6Treatment-Emergent Laboratory Abnormalities in ≥2% of Patients Receiving Fuzeon* (Pooled Studies T20-301 and T20-302 at 48 Weeks)
Laboratory Parameters Grading Fuzeon+Background Regimen
(N=663)
Fuzeon+Background Regimen
(N=663)
Background Regimen
(N=334)
*
Events listed occurred more frequently in patients treated with Fuzeon (based on rates/100 patient-years).
663 patients total 557 total patient-years 162 total patient-years
% frequency rate/100 patient-years rate/100 patient-years
Eosinophilia
   1-2 × ULN (0.7× 109/L) 0.7-1.4 × 109/L 9.1% 10.8 3.7
   >2 × ULN (0.7× 109/L) >1.4 × 109/L 1.8% 2.2 1.8
ALT
   Grade 3 >5-10 × ULN 4.1% 4.8 4.3
   Grade 4 >10 × ULN 1.2% 1.4 1.2
Creatine Phosphokinase (U/L)
   Grade 3 >5-10 × ULN 6.9% 8.3 8.0
   Grade 4 >10 × ULN 2.6% 3.1 8.6

Adverse Events in Pediatric Patients

Fuzeon has been studied in 63 pediatric subjects 5 through 16 years of age with duration of Fuzeon exposure ranging from 1 dose to 134 weeks. Adverse experiences seen during clinical trials were similar to those observed in adult subjects, although infections at site of injection (cellulitis or abscess) were more frequent in adolescents than in adults, with 4 events occurring in 3 of 28 (11%) subjects.

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Side Effects by Body System

General

In general, the most common side effects in patients receiving enfuvirtide and a background regimen have included injection site reactions, diarrhea, nausea, and fatigue.

Local

Local reactions have been reported in 98% of patients and have included pain/discomfort at the injection site (96%), induration (90%), erythema (91%), nodules and cysts (80%), pruritus (65%), ecchymosis (52%), injection site infection (including abscess and cellulitis, 1.7%), minor local bleeding, injection site reactions, injection site mass, injection site inflammation, and injection site edema. The administration of enfuvirtide using the Biojector (R) 2000 needle-free device has been associated with hematomas, bruising, tenderness, and swelling.

Gastrointestinal

Gastrointestinal side effects associated with enfuvirtide and a background regimen have included diarrhea (31.7%), nausea (22.8%), abdominal pain (3.9%), dry mouth (2.1%), pancreatitis (3.0%), abdominal distension, vomiting, flatulence, and oral candidiasis. Constipation, increased amylase, and increased lipase have also been reported; however, causality has not been determined.

Hypersensitivity

Hypersensitivity side effects have included hypersensitivity reactions in less than 1% of patients and in some cases have recurred upon rechallenge. Signs and symptoms of reactions have included rash, fever, nausea, vomiting, chills, rigors, hypotension, elevated liver transaminases, primary immune complex reaction, respiratory distress, glomerulonephritis, and Guillain-Barre syndrome. Worsening of abacavir hypersensitivity reaction has been reported; however, causality has not been established. General allergic reaction (not defined as hypersensitivity reaction) has also been reported.

Metabolic

Metabolic side effects associated with enfuvirtide in combination with a background regimen have included decreased weight (6.6%), decreased appetite (3.2%), anorexia (2.3%), and hyperlipemia. Increased triglycerides and hyperglycemia have also been reported; however, causality has not been established.

Nervous system

Nervous system side effects associated with enfuvirtide and a background regimen have included peripheral neuropathy, taste disturbance, sixth nerve palsy and fatal Guillain-Barre syndrome have also been reported; however, causality has not been established. Dizziness, headache, and epidural abscess have also been reported. The administration of enfuvirtide using the Biojector (R) 2000 needle-free device has been associated with neuralgia and/or paresthesia (nerve pain) lasting up to 6 months when injected at sites where large nerves run close to the skin.

Other

Other side effects reported in patients receiving enfuvirtide and a background regimen have included fatigue (20.2%), herpes simplex (3.5%), influenza-like illness (2.4%), malaise, fever, and chills. Asthenia and sepsis have also been reported; however, causality has not been determined.

Psychiatric

Psychiatric side effects associated with enfuvirtide and a background regimen have included insomnia, depression, anxiety, and suicide attempt; however, causality has not been established. Abnormal thinking and agitation have also been reported.

Respiratory

Respiratory side effects associated with enfuvirtide and a background regimen have included cough (3.9%), sinusitis (6.0%), bronchitis, nasopharyngitis, and upper respiratory tract infection. Pneumonia (2.7%), including fatalities, pneumopathy, and respiratory distress have also been reported; however, causality has not been determined. Patients should be carefully monitored for symptoms of pneumonia.

Dermatologic

Dermatologic side effects associated with enfuvirtide and a background regimen have included folliculitis (2.4%), dermatitis, pruritus, dry skin, skin papilloma, skin discoloration, and rash (not defined as hypersensitivity reaction).

Musculoskeletal

Musculoskeletal side effects associated with enfuvirtide and a background regimen have included myalgia (2.7%), limb pain (2.9%), and increased creatine phosphokinase (Grade 3, 6.9%; Grade 4, 2.6%). Vertebral osteomyelitis has also been reported.

Ocular

Ocular side effects associated with enfuvirtide and a background regimen have included conjunctivitis (2.0%).

Hematologic

Hematologic side effects associated with enfuvirtide and a background regimen have included eosinophilia (1 to 2 times ULN, 9.1%; greater than 2 times ULN, 1.8%), leukopenia, and anemia. Thrombocytopenia, neutropenia, and lymphadenopathy have also been reported; however, causality has not been established.

Renal

Renal side effects have included glomerulonephritis, tubular necrosis, renal insufficiency, and renal failure (including fatalities); however, causality has not been established.

Hepatic

Hepatic side effects associated with enfuvirtide and a background regimen have included increased ALT (Grade 3, 4.1%; Grade 4, 1.2%). Increased AST, increased GGT, toxic hepatitis, and hepatic steatosis have also been reported; however, causality has not been determined.

Cardiovascular

Cardiovascular side effects associated with enfuvirtide and a background regimen have included unstable angina pectoris; however, causality has not been established.

Genitourinary

Genitourinary side effects have included hematuria.

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More resources:

Drugs.com Fuzeon

MedFacts Fuzeon

Micromedex Fuzeon - Includes detailed dosage instructions.

FDA Fuzeon injection

Facts & Comparisons Enfuvirtide

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