DrugLib.com — Drug Information Portal

Rx drug information, pharmaceutical research, clinical trials, news, and more

Rebif (Interferon Beta-1a) - Side Effects and Adverse Reactions



The following adverse reactions are discussed in more detail in the Warnings and Precautions section of the label:

  • Depression and Suicide [see Warnings and Precautions ]
  • Hepatic Injury [see Warnings and Precautions ]
  • Anaphylaxis and Other Allergic Reactions [see Warnings and Precautions (5.3) ]
  • Injection Site Reactions including Necrosis [see Warnings and Precautions ]
  • Decreased Peripheral Blood Counts [see Warnings and Precautions (5.5) ]
  • Seizures [see Warnings and Precautions ]
  • Laboratory Tests [see Warnings and Precautions ]

Clinical Trial Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of REBIF cannot be directly compared to rates in the clinical trials of other drugs and may not reflect the rates observed in practice.

A total of 712 patients with relapsing-remitting multiple sclerosis (RRMS) in two controlled clinical trials took REBIF (22 mcg or 44 mcg given three times per week) [see Clinical Studies ]. Ages ranged from 18 to 55 years. Nearly three-fourths of the patients were female, and more than 90% were Caucasian, largely reflecting the general demographics of the population of patients with multiple sclerosis.

The most commonly reported adverse reactions were injection site disorders, influenza-like symptoms (headache, fatigue, fever, rigors, chest pain, back pain, myalgia), abdominal pain, depression, elevation of liver enzymes and hematologic abnormalities. The most frequently reported adverse reactions resulting in clinical intervention (e.g., discontinuation of REBIF, adjustment in dosage, or the need for concomitant medication to treat an adverse reaction were injection site disorders, influenza-like symptoms, depression, and elevation of liver enzymes [see Warnings and Precautions (5) ].

Study 1 was a 2-year placebo-controlled study in RRMS patients treated with REBIF 22 mcg (n=189), 44 mcg (n=184), or placebo (n=187). Table 3 enumerates adverse reactions and laboratory abnormalities that occurred at an incidence that was at least 2% more in either REBIF-treated group than was observed in the placebo group.

Table 3. Adverse Reactions and Laboratory Abnormalities in Study 1
Body System Placebo tiw
REBIF 22 mcg tiw
REBIF 44 mcg tiw
  Preferred Term % % %
  Influenza-like symptoms 51 56 59
  Headache 63 65 70
  Fatigue 36 33 41
  Fever 16 25 28
  Rigors 5 6 13
  Chest pain 5 6 8
  Malaise 1 4 5
  Injection Site Reaction 39 89 92
  Injection Site Necrosis 0 1 3
  Hypertonia 5 7 6
  Coordination Abnormal 2 5 4
  Convulsions 2 5 4
  Somnolence 1 4 5
  Thyroid Disorder 3 4 6
  Abdominal Pain 17 22 20
  Dry Mouth 1 1 5
  SGPT Increased 4 20 27
  SGOT Increased 4 10 17
  Bilirubinemia 1 3 2
  Myalgia 20 25 25
  Back Pain 20 23 25
  Skeletal Pain 10 15 10
  Leukopenia 14 28 36
  Lymphadenopathy 8 11 12
  Thrombocytopenia 2 2 8
  Anemia 3 3 5
  Rash Erythematous 3 7 5
  Rash Maculo-Papular 2 5 4
  Micturition Frequency 4 2 7
  Urinary Incontinence 2 4 2
  Vision Abnormal 7 7 13
  Xerophthalmia 0 3 1

Adverse reactions in Study 2, a 1-year active-controlled (vs. interferon beta-1a, 30 mcg once weekly intramuscular injection, n=338) study including 339 patients with MS treated with REBIF were generally similar to those in Study 1, taking into account the disparity in study durations.


Anaphylaxis and other allergic reactions have been observed with the use of REBIF [see Warnings and Precautions]. As with all therapeutic proteins, there is a potential for immunogenicity. In Study 1, the presence of neutralizing antibodies (NAb) to REBIF was determined by collecting and analyzing serum pre-study and at 6 month time intervals during the 2 years of the clinical trial. Serum NAb were detected in 59/189 (31%) and 45/184 (24%) of REBIF-treated patients at the 22 mcg and 44 mcg three times per week doses, respectively, at one or more times during the study. The data reflect the percentage of patients whose test results were considered positive for antibodies to REBIF using an antiviral cytopathic effect assay, and are highly dependent on the sensitivity and specificity of the assay. Additionally, the observed incidence of NAb positivity in an assay may be influenced by several factors including sample handling, timing of sample collection, concomitant medications and underlying disease. For these reasons, comparison of the incidence of antibodies to REBIF with the incidence of antibodies to other products may be misleading.

Postmarketing Experience

The following adverse reactions have been identified during post-approval use of REBIF. 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.

Autoimmune Disorders: Drug-induced lupus erythematosus, autoimmune hepatitis

Blood and Lymphatic System Disorders: Thrombotic thrombocytopenic purpura/hemolytic uremic syndrome (TTP/HUS)

Eye Disorders: Retinal vascular disorders (i.e. retinopathy, cotton wool spots or obstruction of retinal artery or vein)

Skin and Subcutaneous Tissue Disorders: Erythema multiforme, Stevens-Johnson syndrome


Below is a sample of reports where side effects / adverse reactions may be related to Rebif. The information is not vetted and should not be considered as verified clinical evidence.

Possible Rebif side effects / adverse reactions in 42 year old female

Reported by a consumer/non-health professional from Germany on 2011-10-04

Patient: 42 year old female

Reactions: Breast Cancer, Impaired Healing

Adverse event resulted in: hospitalization

Suspect drug(s):

Possible Rebif side effects / adverse reactions in 60 year old female

Reported by a consumer/non-health professional from Greece on 2011-10-04

Patient: 60 year old female

Reactions: Breast Cancer

Adverse event resulted in: hospitalization

Suspect drug(s):

Possible Rebif side effects / adverse reactions in 55 year old male

Reported by a consumer/non-health professional from Greece on 2011-10-04

Patient: 55 year old male

Reactions: Laryngeal Cancer

Adverse event resulted in: hospitalization

Suspect drug(s):

See index of all Rebif side effect reports >>

Drug label data at the top of this Page last updated: 2014-05-21

-- advertisement -- The American Red Cross
Home | About Us | Contact Us | Site usage policy | Privacy policy

All Rights reserved - Copyright DrugLib.com, 2006-2015