FDA-filed SPL labeling · retrieved through openFDA

Talimogene Laherparepvec Injection

Talimogene laherparepvec (Imlygic) is a genetically modified oncolytic viral therapy injected directly into melanoma lesions that cannot be surgically removed.

Brand name Imlygic
Rx Form 1 Route Intralesional
Dr. Brian Staiger, PharmD, BCPS
Reviewed by Last reviewed Jul 10, 2026
🧬 Where this information comes from Click to expand

The clinical label records used on this page are FDA-filed Structured Product Labeling (SPL) retrieved through openFDA. We identified 1 clinical label set within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. Forms, routes, brands, labelers, strengths, and NDC product-record counts are built separately from matching FDA National Drug Code Directory records. The linked DailyMed document is a representative official source for verification, not the page’s only clinical source. View the linked label on DailyMed →

At a glance
Linked label effectiveApr 4, 2025
AvailabilityRx
Earliest approval/marketing year ⓘ2015
FDA-listed product records ⓘ8
Boxed warningNone found in compared labels
How we combine label and product data →
✓No current FDA shortage listed · checked Sep 27, 2026
⭐ Talimogene Laherparepvec Injection at a glance The quick version — the full detail is in the Patient Information Guide below.
💊
HelloPharmacist Editorial Team Bottom Line
Imlygic is a specialized therapy injected directly into melanoma skin and lymph node lesions that can't be surgically removed. It has not been proven to extend life or treat melanoma that has spread to internal organs, so it is just one part of a broader treatment plan. Because it is a live virus, strict safety precautions are needed to protect both patients and those around them.

📖 Talimogene Laherparepvec Injection: Patient Information Guide

A plain-language walkthrough of Talimogene Laherparepvec Injection — what it treats, how it works, how it’s taken, side effects, warnings and interactions. Tap any section to expand it.

🎯What it's used for▾

Imlygic (talimogene laherparepvec) is approved for one specific use in melanoma treatment:

  • Imlygic is used for the local treatment of unresectable (surgically unremovable) cutaneous (skin surface), subcutaneous (just beneath the skin), and nodal (lymph node) melanoma lesions in patients whose melanoma has returned after initial surgery.
  • Imlygic is injected directly into lesions that are visible, felt by touch (palpable), or detected by ultrasound.
  • Important limitation: Imlygic has not been shown to improve overall survival or to affect melanoma that has spread to internal organs (visceral metastases).
⚙️How it works▾

Imlygic is a herpes simplex virus that has been genetically engineered to do two things inside tumor tissue: replicate (multiply) within cancer cells until they burst open (lyse), and produce GM-CSF, an immune-stimulating protein. When tumor cells burst, they release cancer-associated proteins that, together with GM-CSF, may help the body's immune system recognize and attack cancer cells. The exact chain of events that leads to any anti-tumor effect is not fully understood.

💊How it's taken▾

Imlygic is given by a healthcare provider as a direct injection into lesions — it is never given into a vein or by any other route. The first dose is followed by a second dose three weeks later; all doses after that are given every two weeks. Treatment is typically continued for at least six months, unless all injectable lesions resolve or another treatment becomes necessary.

  • The total injection volume at any single visit cannot exceed 4 mL across all lesions combined.
  • The largest lesions are injected first; new lesions appearing since the last visit are prioritized in subsequent sessions.
  • If a complete response is achieved and new unresectable lesions later appear, treatment may be restarted.
🤒Side effects — in detail▾

Most side effects reported with Imlygic were mild to moderate and tended to resolve within about 72 hours. The most common ones include:

  • Fatigue
  • Chills
  • Fever
  • Nausea
  • Flu-like illness
  • Injection site pain
  • Vomiting
  • Headache
  • Muscle aches (myalgia)
  • Joint pain (arthralgia)

Serious reactions to watch for include spreading herpes infection (especially in immunocompromised individuals), skin or tissue breakdown at the injection site, immune-mediated events like kidney inflammation or pneumonitis (lung inflammation), and airway problems. Call your doctor right away if any of these occur.

⚠️Warnings & precautions▾
  • Live virus risk: Imlygic is a live, modified herpes virus. It can be transmitted through accidental contact with injection sites, dressings, or body fluids. Close contacts — especially those who are immunocompromised or pregnant — must avoid direct contact with treated areas.
  • Herpetic infection: Serious and even fatal herpes infections have been reported, particularly in immunocompromised patients. Patients who develop herpes-like sores should follow hygiene precautions and contact their doctor.
  • Injection site complications: Tissue breakdown (necrosis), ulceration, poor wound healing, and bacterial infections including cellulitis have occurred. One patient required limb amputation after a non-healing infected wound.
  • Immune-mediated events: Imlygic can trigger immune reactions including kidney inflammation (glomerulonephritis), blood vessel inflammation (vasculitis), lung inflammation (pneumonitis), and worsening of pre-existing autoimmune conditions.
  • Airway risk: Airway obstruction has been reported when lesions near major airways were injected — use with caution in those locations.
  • Do NOT give via the liver: Imlygic is not approved for injection through the skin into the liver. This route has caused hospitalizations and deaths from liver bleeding.
🔀What it interacts with▾

There is only one known drug interaction class identified for Imlygic:

  • Antiviral agents (e.g., acyclovir, valacyclovir): These medicines treat herpes infections but can also interfere with Imlygic's ability to work, since Imlygic is itself a herpes-based virus that is sensitive to acyclovir. If you develop a herpes infection during treatment, your doctor will need to weigh the risk of treating the infection against the impact on Imlygic's effectiveness.

This is not a complete list of interactions. Always talk with your doctor or pharmacist before starting, stopping, or changing any medication.

📋Before taking it▾
  • Weakened immune system (immunocompromised): Do not use Imlygic if you have HIV/AIDS, leukemia, lymphoma, or are on immunosuppressive therapy — risk of life-threatening herpes infection.
  • Pregnancy: Do not use Imlygic during pregnancy. Women who can become pregnant should use effective contraception throughout treatment.
  • Breastfeeding: It is unknown whether Imlygic passes into breast milk. Discuss with your doctor whether to stop breastfeeding or stop treatment.
  • Children: Safety and effectiveness have not been established in pediatric patients.
  • Older adults (65+): No meaningful differences in safety or effectiveness were seen compared to younger patients in clinical studies.
  • Autoimmune disease: Discuss risks and benefits with your doctor before starting Imlygic if you have an underlying autoimmune condition.
  • Multiple myeloma: A plasmacytoma (a type of plasma cell tumor) was reported near an injection site in a patient with smoldering multiple myeloma — discuss risks carefully with your doctor.
  • Poor wound healing history: Prior radiation at injection sites or poor blood supply to lesion areas may increase the risk of wound complications.
🚑If you take too much▾

There is no clinical experience with an Imlygic overdose. No dose-limiting toxicity was observed in clinical studies at the maximum studied doses. If an overdose is suspected, treatment is supportive and symptomatic — meaning your care team will monitor and treat any symptoms that arise.

🔬Pharmacokinetics — how your body processes it▾

After injection, Imlygic DNA spreads beyond the injection site and has been detected in blood, urine, oral mucosa (mouth lining), and the anogenital area during treatment. The highest concentration is found at the injected tumor itself. In clinical studies, Imlygic DNA was no longer detectable in blood and urine within 30 days after the end of treatment, and not detectable at injection sites within 60 days after treatment ended. Infectious (active) virus was detected at injection sites in a small number of patients early in treatment but was not found after the second cycle of treatment.

📦How to store it▾

Store and transport IMLYGIC at −90°C to −70°C (−130°F to −94°F). Store IMLYGIC in the carton until use.

📄 Written from Talimogene Laherparepvec Injection’s FDA-approved label information, summarized in plain language with AI, and reviewed by our pharmacy team before publication. Every point is grounded in that labeling — nothing is invented. How we use AI →

🩺 Pharmacist Counseling Corner

Quick, plain-English answers to the questions patients ask most about Talimogene Laherparepvec Injection — the kind of thing our pharmacy team would talk through with you at the counter.

What exactly is Imlygic and how is it different from chemotherapy? ▾
Imlygic is a genetically modified herpes virus — not a chemotherapy drug. Instead of using chemicals to kill cancer cells, it's injected directly into your melanoma lesions, where it replicates inside the tumor cells and causes them to burst. At the same time, it releases a protein that may help your immune system fight the cancer. It treats the lesions it's injected into, but it has not been shown to affect melanoma that has spread to internal organs or to extend overall survival.
How often will I need to come in for injections? ▾
Your first injection is followed by a second one three weeks later. After that, you'll come in every two weeks. In general, treatment continues for at least six months, as long as there are lesions to inject and no other treatment is needed first. Your care team will track your response and adjust the plan as needed.
What side effects should I expect, and when should I call my doctor? ▾
Most people feel flu-like symptoms — fatigue, chills, fever, nausea — especially in the first few months of treatment. These are common and usually pass within a few days. You should call your doctor right away if you notice herpes-like sores or blisters (especially in places that weren't injected), trouble breathing, signs of infection at the injection site like spreading redness or pus, or any new and unusual symptoms like blood in your urine or worsening skin conditions.
Is Imlygic contagious — can I spread it to my family? ▾
Because Imlygic is a live virus, there is a small risk of transmitting it through direct contact with your injection sites, used dressings, or body fluids. Keep your injection sites covered for at least a week after each treatment. Household members, caregivers, and especially anyone who is pregnant or has a weakened immune system should avoid touching your injection sites or dressings. Caregivers helping you change dressings should wear gloves.
Can I take acyclovir or other cold sore medicines while on Imlygic? ▾
This is an important one to talk to your doctor about before taking anything. Acyclovir and similar antiviral medicines work against herpes viruses — but Imlygic itself is a modified herpes virus. Taking antivirals could reduce how well Imlygic works. If you develop a herpes outbreak during treatment, your doctor will need to carefully weigh the benefit of treating it against the potential impact on your cancer therapy.
Is Imlygic safe if I'm pregnant or trying to get pregnant? ▾
Imlygic should not be used during pregnancy. There are no human studies, but because it's a live herpes-based virus, there is a potential risk to a fetus or newborn. If you could become pregnant, you should use reliable contraception throughout treatment. If you become pregnant while receiving Imlygic, contact your doctor right away to discuss your options.
Is Talimogene Laherparepvec Injection available over the counter? ▾
Talimogene Laherparepvec Injection is dispensed by prescription according to its FDA labeling, so it isn't sold over the counter. Your prescriber and pharmacist will determine if it's appropriate for you.
When was Talimogene Laherparepvec Injection first available? ▾
Talimogene Laherparepvec Injection has been available in the United States since at least 2015, based on FDA approval history (Drugs@FDA) and product marketing records.
Who makes Talimogene Laherparepvec Injection? ▾
Talimogene Laherparepvec Injection is supplied by 2 manufacturers listed in the FDA NDC Directory, including Amgen Inc, IDT Biologika GmbH.

💬 Answers drafted from Talimogene Laherparepvec Injection’s FDA-approved label information, summarized in plain language with AI, and reviewed by our pharmacy team before publication. Grounded in that labeling — nothing is made up. How we use AI →

🧰 Keep exploring

💊 How Talimogene Laherparepvec Injection comes

Talimogene Laherparepvec Injection is available in 1 form. Different forms and brands can have different approved uses, doses, schedules, and directions. Follow the instructions for your exact product, and do not switch forms without guidance from your prescriber or pharmacist.

Injection

By injection · Intralesional
Brands Imlygic
How this form is used
What it may be used for
  • Imlygic is injected directly into unresectable (cannot be surgically removed) cutaneous, subcutaneous, or nodal melanoma lesions that have returned after initial surgery
  • Imlygic is not for melanoma that has spread to internal organs, and has not been shown to improve overall survival
Important instructions
  • Imlygic is administered by a healthcare provider by direct intralesional injection only — never into a vein
  • Imlygic vials must be thawed at room temperature before use and administered immediately or stored under specific conditions; they must never be refrozen
  • After each treatment visit, Imlygic injection sites must be kept covered with an occlusive dressing for at least one week or until the site stops weeping
  • Imlygic is generally given on a schedule: initial dose, then a second dose three weeks later, then every two weeks thereafter for at least six months
Available strengths 2 strengths
8 FDA-listed product records ⓘ

📊 Talimogene Laherparepvec Injection across the U.S. market

How Talimogene Laherparepvec Injection appears in the FDA’s National Drug Code Directory — including its dosage forms, strengths, brand names, manufacturers, and FDA-listed product records. These are directory records, not sales or prescription volume.

1
Dose forms ⓘ
2
Manufacturers
1
Brand names
8
FDA-listed product records ⓘ
2015
First marketed ⓘ
Amgen Inc75%
IDT Biologika GmbH25%

Share of FDA-listed product records by manufacturer — FDA National Drug Code Directory. Record counts are not sales or prescription volume.

📈 How widely Talimogene Laherparepvec Injection is used

A general measure of how commonly Talimogene Laherparepvec Injection is prescribed, based on Medicaid — one of the largest public drug programs. The figure below is prescriptions filled in Q1–Q4 2025, summed across every form and brand of the drug.

Think of this as a proxy for how widely Talimogene Laherparepvec Injection is used, drawn from freely available public data. Medicaid is just one program — these numbers don’t include Medicare, other government coverage, or commercial and cash-pay prescriptions, so real-world use is higher than what’s shown here.

22
Medicaid prescriptions filled (Q1–Q4 2025)
$208,308 gross Medicaid reimbursement (before mandatory rebates — net cost is lower)

How commonly is Talimogene Laherparepvec Injection prescribed? Of the 1,597 medications we measure, Talimogene Laherparepvec Injection ranks #1,571 by Medicaid prescriptions — more than 2% of them.

Where Talimogene Laherparepvec Injection ranks among the drugs we measure · Q1–Q4 2025 · neighbors ±5

Utilization by Talimogene Laherparepvec Injection product

Pick a product to see its own Medicaid numbers. Each chip is one clinical product — a specific strength & dosage form as defined by RxNorm — with brand-name and generic versions combined.

Other Talimogene Laherparepvec Injection products — combination packs and listings not yet matched to a specific clinical product (kept visible so every prescription is accounted for)

22 Medicaid prescriptions (Q1–Q4 2025) 100% of Talimogene Laherparepvec Injection prescriptions shown $208,308 gross reimbursement (before rebates) ≈ $9,469 per prescription (gross)

Summed across the 1 of 4 listed NDC products with Medicaid activity.

Shares are of the Medicaid prescriptions shown here. Product grouping follows RxNorm (the National Library of Medicine’s drug terminology), so “one product” means one strength & dosage form regardless of manufacturer. Dollar figures are gross Medicaid reimbursement before mandatory rebates — rebates (often large, especially for brand-name drugs) are confidential, so actual net cost to Medicaid is lower than shown.

Source: Medicaid State Drug Utilization Data (CMS), aggregated by generic ingredient — summed across every NDC (all brands, strengths, salt forms and dosage forms) of Talimogene Laherparepvec Injection, and across all states and both fee-for-service and managed-care claims. A general popularity signal; it excludes Medicare, commercial insurance and cash prescriptions, so it is not total U.S. use. Based on the 1 of 4 listed Talimogene Laherparepvec Injection NDCs with Medicaid activity.

🔍 Compare Talimogene Laherparepvec Injection products

A representative set of FDA-listed product records for Talimogene Laherparepvec Injection — across manufacturers, strengths, and dosage forms, grouped by form with each product’s manufacturer and how the FDA approved it. The same medicine may be made and packaged by different companies, so a single drug can have many directory entries. (It’s also why a refill can look different — a new shape, color, or box — even though it contains the same medication.)

Strength Route Manufacturer / Labeler Category ⓘ Details
💊Injection
1000000 [PFU]/mL Intralesional Amgen Inc × 3 listings BLA View NDC →
100000000 [PFU]/mL Intralesional Amgen Inc × 3 listings BLA View NDC →
1000000 [PFU]/mL — IDT Biologika GmbH DRUG FOR FURTHER PROCESSING View NDC →
100000000 [PFU]/mL — IDT Biologika GmbH DRUG FOR FURTHER PROCESSING View NDC →

Showing 8 of 8 products — FDA National Drug Code Directory. See every product, package size and price: browse all 8 Talimogene Laherparepvec Injection NDCs →

🏷️ Sold under these brand names

Imlygic

🏭 Manufacturers & labelers

Amgen Inc 6 IDT Biologika GmbH 2

RxNorm drug class

Talimogene Laherparepvec Injection belongs to the Antineoplastic cell and gene therapy class.

Drug family (ATC) Antineoplastic cell and gene therapy

Classified by RxNorm RxClass — the U.S. National Library of Medicine's standardized drug-classification service (Established Pharmacologic Class from the FDA, the ATC drug family from the WHO, and mechanism of action). Reference only, not medical advice.

🔬 Where this comes from

Core label, product, RxNorm, safety, and utilization data on this page come from the sources identified below. AI-written, editorial, and licensed sections are labeled separately.

📄
FDA-filed drug labels (SPL) Uses, dosing, warnings & side effects from SPL records retrieved through openFDA; the linked representative set can be verified on DailyMed. ✓ Linked label effective Apr 4, 2025
🏭
Forms, brands & labelersAggregated from ingredient-matched FDA National Drug Code Directory product records for Talimogene Laherparepvec Injection.
📈
Real-world reportsThe FDA Adverse Event Reporting System (FAERS), served through openFDA.
🚨
Recalls & shortagesopenFDA drug-enforcement reports and the FDA drug-shortage database.
🧾 Clinical label set — FDA-filed SPL labels retained for Talimogene Laherparepvec Injection after exact ingredient or ingredient-combination matching and applicable route/form matching
Clinical labels in scope
1
NDC products indexed
8
Distinct labelers/manufacturers represented
2
Linked representative label ⓘ
Amgen Inc
Linked label effective
Apr 4, 2025
Composite sections available
21
Linked SPL Set ID
64ffb680-ea8c-42fc-9649-9e8c0eb77ddb
Linked SPL Document ID
4d1843a8-7a83-4062-ba8c-4f97e2f1427b
Open the linked representative label on DailyMed ↗

How we combine label and product data

HelloPharmacist combines public FDA and NLM records; we don’t author the underlying clinical facts. We identified 1 FDA-filed SPL label set within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. The representative label is the starting point for the displayed reference monograph; the 12 largest stored in-scope SPL records, which may include that representative, are compared section by section, and the longest available version of each section is retained. Forms, routes, brands, labelers, product-listed strengths, and product-record counts are aggregated separately from ingredient-matched FDA NDC Directory records; package records listed above are associated with the linked SPL; and the normalized concept hierarchy comes from NLM RxNorm.

Where a section is identified as AI-written, its plain-language text is generated from bounded label evidence. New draft drug pages remain in the admin review queue before first publication. Amgen Inc is the representative DailyMed label linked for verification and dates; it is not the sole source used for the page.

This is general education, not medical advice — always consult your doctor or pharmacist about your medications and any medical condition. For the exact wording of the linked representative label, view that label on DailyMed; some displayed composite sections may come from other in-scope SPL labels. Learn how we use AI and our data sources & update cadence.