Last updated on RxList: 10/16/2019
Imlygic Side Effects Center

Last reviewed on RxList 10/16/2019

Imlygic (talimogene laherparepvec) suspension for intralesional injection is a genetically modified oncolytic viral therapy indicated for the local treatment of unresectable cutaneous, subcutaneous, and nodal lesions in patients with melanoma recurrent after initial surgery. Common side effects of Imlygic include:

  • fatigue,
  • chills,
  • fever,
  • nausea,
  • influenza-like illness,
  • injection site pain,
  • nausea,
  • vomiting,
  • diarrhea,
  • constipation,
  • abdominal pain,
  • joint pain muscle pain,
  • pain in extremities,
  • headache,
  • dizziness,
  • mouth and throat pain, and
  • weight loss

The recommended starting dose of Imlygic is up to a maximum of 4 mL at a concentration of 106 (1 million) plaque-forming units (PFU) per mL. Subsequent doses of Imlygic should be administered up to 4 mL at a concentration of 108 (100 million) PFU per mL. Imlygic may interact with acyclovir or other antiherpetic viral agents. Tell your doctor all medications and supplements you use. Imlygic is not recommended for use during pregnancy. Women should use contraception to prevent pregnancy during treatment with Imlygic. Imlygic is not recommended for use while breastfeeding.

Our Imlygic (talimogene laherparepvec) suspension for intralesional injection Side Effects Drug Center provides a comprehensive view of available drug information on the potential side effects when taking this medication.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.


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Imlygic Consumer Information

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have any signs that you may be developing herpes simplex virus, such as:

  • tingling, burning, or pain (especially around your mouth or genitals);
  • weakness or cramps in an arm or leg, sometimes with burning pain;
  • eye pain, crusting or drainage, blurred vision (your eyes may be more sensitive to light);
  • confusion, severe drowsiness; or
  • blisters forming on your fingers or ears, or around your mouth or genitals.

Also call your doctor if you have:

  • any skin lesion that will not heal; or
  • redness, swelling, warmth, oozing, or skin changes where the injection was given.

Common side effects may include:

  • fever, chills, flu-like symptoms;
  • feeling tired;
  • nausea; or
  • pain where the medicine was injected.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Read the entire detailed patient monograph for Imlygic (Talimogene Laherparepvec Suspension for Intralesional Injection)


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Imlygic Professional Information


The most commonly reported adverse drug reactions (≥ 25%) in IMLYGIC-treated patients were fatigue, chills, pyrexia, nausea, influenza-like illness, and injection site pain.

The following adverse reactions are discussed in greater detail in another section of the label:

  • Herpetic Infection [see WARNINGS AND PRECAUTIONS]
  • Injection Site Complications [see WARNINGS AND PRECAUTIONS]

Clinical Trials Experience

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 safety of IMLYGIC was evaluated in 419 patients who received at least 1 dose of either IMLYGIC (n = 292) or subcutaneously administered granulocyte-macrophage colony-stimulating factor (GM-CSF) (n = 127) in an open-label, randomized clinical study of patients with stage IIIB, IIIC, and IV melanoma that was not considered to be surgically resectable [see Clinical Studies]. The median duration of exposure to IMLYGIC was 23 weeks (5.3 months). Twenty-six patients were exposed to IMLYGIC for at least 1 year.

Most adverse reactions reported were mild or moderate in severity and generally resolved within 72 hours. The most common grade 3 or higher adverse reaction was cellulitis [see WARNINGS AND PRECAUTIONS].

Pyrexia, chills, and influenza-like illness can occur any time during IMLYGIC treatment but were more frequent during the first 3 months of treatment.

Table 4 below lists adverse reactions with a 5% or greater incidence in the IMLYGIC arm compared to the GM-CSF arm in the clinical study [see Clinical Studies].

Table 4. Advers e Reactions Reported with At Leas t a 5% Greater Incidence in Patients Treated with IMLYGIC Compared to GM-CSF

Adverse Reactions IMLYGIC
(n = 292)
(n = 127)
Any Grade
n (%)
Grade 3
n (%)
Any Grade
n (%)
Grade 3
n (%)
General disorders and administrationsite conditions
  Fatigue 147 (50.3) 6 (2.1) 46 (36.2) 1 (< 1)
  Chills 142 (48.6)   11 (8.7)  
  Pyrexia 125 (42.8)   11 (8.7)  
  Influenza-like illness 89 (30.5) 2 (< 1) 19 (15.0)  
  Injection site pain 81 (27.7) 2 (< 1) 8 (6.3)  
Gastrointestinal dis orders
  Nausea 104 (35.6) 1 (< 1) 25 (19.7)  
  Vomiting 62 (21.2) 5 (1.7) 12 (9.5)  
  Diarrhea 55 (18.8) 1 (< 1) 14 (11.0)  
  Constipation 34 (11.6)   8 (6.3) 1 (< 1)
  Abdominal pain 26 (8.9) 2 (< 1) 3 (2.4)  
Musculoskeletal and connectivetissue disorders
  Myalgia 51 (17.5) 1 (< 1) 7 (5.5)  
  Arthralgia 50 (17.1) 2 (< 1) 11 (8.7)  
  Pain in extremity 48 (16.4) 4 (1.4) 12 (9.5) 1 (< 1)
Nervous system disorders
  Headache 55 (18.8) 2 (< 1) 12 (9.5)  
  Dizziness 28 (9.6)   4 (3.2)  
Respiratory, thoracic, and mediastinal disorders
  Oropharyngeal pain 17 (5.8)   1 (< 1)  
  Weight decreased 17 (5.8) 1 (< 1) 1 (< 1)  

Other adverse reactions associated with IMLYGIC in the open-label, randomized study include rash, dermatitis, glomerulonephritis, vitiligo, worsening psoriasis, cellulitis, pneumonitis, vasculitis, herpetic keratitis, obstructive airway disorder, plasmacytoma at the injection site, deep vein thrombosis, and oral herpes.

Read the entire FDA prescribing information for Imlygic (Talimogene Laherparepvec Suspension for Intralesional Injection)

© Imlygic Patient Information is supplied by Cerner Multum, Inc. and Imlygic Consumer information is supplied by First Databank, Inc., used under license and subject to their respective copyrights.

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