Imlygic Side Effects

Generic name: talimogene laherparepvec

Medically reviewed by Drugs.com. Last updated on Mar 1, 2025.

Note: This document provides detailed information about Imlygic Side Effects associated with talimogene laherparepvec. Some dosage forms listed on this page may not apply specifically to the brand name Imlygic.

Applies to talimogene laherparepvec: injection suspension.

Precautions

Your doctor will check your progress closely while you are receiving this medicine. This will allow your doctor to see if the medicine is working properly and to decide if you should continue to receive it. Blood tests may be needed to check for unwanted effects.

Using this medicine while you are pregnant can harm your unborn baby. Use an effective form of birth control to keep from getting pregnant. If you think you have become pregnant while using the medicine, tell your doctor right away.

This medicine can spread to other areas of the body or to other people (eg, household members, caregiver, or persons sharing the same bed). To avoid spreading the medicine:

• Avoid direct contact between your treatment sites, dressings, body fluids or close contacts. Do not touch or scratch the treatment sites.
• Wear gloves when putting on or changing your dressings.
• Cover the treatment sites with airtight and watertight dressings for at least 1 week after each treatment.
• If the dressing comes loose or falls off, use a new, clean dressing to replace it.
• Place all used dressings and cleaning materials in a sealed plastic bag and throw them in the trash can.

This medicine may cause herpes infections (including cold sores). Tell your doctor right away if you have pain, burning, or tingling in a blister around the mouth or genitals or on the fingers or ears, confusion, extreme drowsiness, blurred vision, eye pain, sensitivity to light, or weakness in your arms or legs.

This medicine may cause delayed healing at the injection site. It is more likely to occur if you had previous radiation treatment at the injection site or lesions. Tell your doctor right away if you have infection or delayed healing of the injection sites.

Immune-mediated events may occur while receiving this medicine. These include glomerulonephritis, pneumonitis, psoriasis, vasculitis, or vitiligo. Tell your doctor if you have bloody or cloudy urine, swelling of the feet or lower legs, weight gain, fever, sores, welting, or blisters, or red, scaling, or crusted skin.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

Serious side effects of Imlygic

Along with its needed effects, talimogene laherparepvec (the active ingredient contained in Imlygic) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor or nurse immediately if any of the following side effects occur while taking talimogene laherparepvec:

Other side effects of Imlygic

Some side effects of talimogene laherparepvec may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

See also:

For healthcare professionals

Applies to talimogene laherparepvec: injectable suspension.

General adverse events

The most commonly reported (25% or more) adverse drug reactions were fatigue, chills, pyrexia, nausea, influenza-like illness, and injection site pain.

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

Most adverse reactions were mild or moderate in severity and generally resolved within 72 hours.

Cellulitis was the most common grade 3 or higher adverse reaction.^[Ref]

Other

• Very common (10% or more): Fatigue (50.3%), chills (48.6%), pyrexia (42.8%), influenza-like illness (30.5%), injection site pain (27.7%)
• Common (1% to 10%): Decreased weight
• Frequency not reported: Herpetic infection, injection site complications (cellulitis, systemic bacterial infection, impaired healing)^[Ref]

Gastrointestinal

• Very common (10% or more): Nausea (35.6%), vomiting (21.2%), diarrhea (18.8%), constipation (11.6%)
• Common (1% to 10%): Abdominal pain
• Frequency not reported: Oral herpes^[Ref]

Nervous system

• Very common (10% or more): Headache (18.8%)
• Common (1% to 10%): Dizziness^[Ref]

Musculoskeletal

• Very common (10% or more): Myalgia (17.5%), arthralgia (17.1%), extremity pain (16.4%)^[Ref]

Immunologic

• Frequency not reported: Immune-mediated events (glomerulonephritis, vasculitis, pneumonitis, psoriasis, vitiligo)^[Ref]

Oncologic

• Frequency not reported: Plasmacytoma^[Ref]

Respiratory

• Common (1% to 10%): Oropharyngeal pain^[Ref]

Metabolic

• Common (1% to 10%): Decreased weight^[Ref]

Further information

Imlygic side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Note: Medication side effects may be underreported. If you are experiencing side effects that are not listed, submit a report to the FDA by following this guide.

Medical Disclaimer