Interleukin-2 - Market Share Analysis, Industry Trends & Statistics, Growth Forecasts (2026-2031)

The interleukin-2 market size was valued at USD 1.67 billion in 2025 and is estimated to grow from USD 1.78 billion in 2026 to reach USD 2.44 billion by 2031, at a CAGR of 6.5% during the forecast period (2026-2031). This report is segmented by Product Type (Aldesleukin, Denileukin Difftitox, and More), Route of Administration (Intravenous, Subcutaneous, Others), Indication (Renal Cell Carcinoma, Melanoma, and More), End User (Hospitals and Clinics, Academic Medical Centers, and More), and Geography (North America, Europe, Asia-Pacific, and More). The Market Forecasts are Provided in Terms of Value (USD).

Global Interleukin-2 Market Trends and Insights

Expansion of IL-2 Use in Tumor-Infiltrating Lymphocyte Therapy

High-dose IL-2 supports the persistence and activity of tumor-infiltrating lymphocytes (TILs) after infusion. Without adequate signaling support, infused cells can contract rapidly and lose therapeutic effect. A meta-analysis of 13 TIL studies involving 617 patients with advanced melanoma reported a 34% objective response rate following prior anti-PD-(L)1 treatment. New manufacturing protocols combine IL-2 with IL-15 and IL-21 in closed perfusion bioreactors to improve product quality and reduce exhaustion markers, potentially expanding eligibility for TIL-based combination therapies in the Interleukin-2 market.

Iovance studied IOV-3001, a modified IL-2 fusion protein designed to expand effector T cells while limiting regulatory T-cell activation. The company planned Phase II advancement of a low-dose TIL regimen in 2026 to support a less burdensome treatment model. Australia approved Amtagvi (lifileucel) for previously treated advanced melanoma in June 2026, expanding access to TIL therapy outside the United States. This development supported demand for companion IL-2 products administered after cell infusion.

Growth of Engineered IL-2 Receptor-Biased Therapies

Engineered IL-2 programs target IL-2Rβγ, or CD122/CD132, activity toward effector T cells and natural killer cells while reducing CD25, or IL-2Rα, signaling. This approach aims to limit regulatory T-cell activation and vascular toxicity. Medicenna reported a 42% objective response rate and an 83% disease control rate among 12 evaluable patients with checkpoint-resistant solid tumors treated with MDNA11. In the ABILITY-1 Phase I/II study, 55 monotherapy patients across 18 cancer types reported a 24% objective response rate after checkpoint inhibitor failure.

A first-in-human Phase I study of a no-alpha IL-2 mutein reported a 60% disease control rate at 12 months at the recommended Phase II dose of 1,200 IU/kg. The study also reported 60% CD8 T-cell Ki67 proliferation and 87% natural killer cell proliferation without vascular leak syndrome. AstraZeneca is evaluating AZD6750, a CD8-guided cytokine designed to restrict activity to intratumoral CD8+ T cells. A Phase I/II study of AZD6750 with rilvegostomig is enrolling under NCT07115043.

High-Dose IL-2 Toxicity and Intensive-Care Requirements

High-dose aldesleukin has a demanding clinical safety profile. A study of 391 patients found that 87% experienced hypotension, while 73% experienced vascular leak syndrome or edema. The need for intensive monitoring restricts administration to large academic centers with appropriate clinical infrastructure. Limited ICU oncology capacity in Brazil, India, and parts of the Middle East and Africa further limits patient access. The short half-life of conventional aldesleukin increases the treatment burden in the Interleukin-2 market, as dosing may be required every 8 hours. Post-infusion IL-2 toxicity also affects the TIL therapy pathway. Lifileucel regimens showed a 7.5% treatment-related mortality rate in the cited analysis. Iovance received FDA IND clearance in June 2026 for IOV-5001, an IL-12-tethered TIL therapy designed without post-infusion IL-2.

Other drivers and restraints analyzed in the detailed report include:

• Increasing Adoption of IL-2 and Checkpoint-Inhibitor Combinations
• Rising Demand for Low-Dose IL-2 in Autoimmune Disease
• Substitution From Checkpoint Inhibitors and Other Immunotherapies

Segment Analysis

Aldesleukin held 65.45% of product revenue in 2025, supported by more than three decades of clinical use and the lack of a broadly approved replacement. This established base continues to underpin the Interleukin-2 market. Engineered IL-2 receptor agonists are the fastest-growing product segment, with a projected CAGR of 6.92% during 2026-2031. By January 2026, Medicenna had enrolled more than 110 patients across 29 cancer types in the ABILITY-1 Phase 1/2 study and reported a 50% objective response rate in second- and third-line settings. Anaveon presented Phase 1 data for ANV600 at ASCO 2026, established a recommended Phase 2 dose, and reported tumor shrinkage in post-checkpoint and checkpoint-naive patients.

Denileukin diftitox, marketed as LYMPHIR and REMITORO, is the second-largest product category, with revenue generated primarily from cutaneous T-cell lymphoma treatment and ongoing development in diffuse large B-cell lymphoma. Pegylated IL-2 products and fusion proteins remain smaller categories but hold strategic importance. Nektar initiated Phase 3 ZENITH AD trials of rezpegaldesleukin for atopic dermatitis in July 2026; positive results could establish the first approved pegylated IL-2 product for a major autoimmune indication. Krystal received FDA RMAT designation for KB707 in advanced NSCLC in February 2026. KB707 delivers localized IL-2 and IL-12 expression through inhalation, adding a differentiated delivery model to the Interleukin-2 market.

Intravenous delivery held 88.65% of route-of-administration revenue in 2025, reflecting the use of high-dose aldesleukin through monitored intravenous infusion. Subcutaneous administration is projected to grow at a CAGR of 7.44% during 2026-2031. Low-dose autoimmune protocols commonly use subcutaneous injections every other day, while engineered IL-2 products are increasingly moving toward formulations that support outpatient delivery. A mixed-methods analysis found that subcutaneous immunotherapy reduced treatment time by 85% to 90% compared with intravenous administration, generated annual savings of EUR 1,410 (USD 1,537) per patient, and reduced oncology day-hospital occupancy by 40%.

In the June 2026 survey, 92% of patients preferred subcutaneous delivery when efficacy and safety were equivalent, while 82% of healthcare professionals supported out-of-hospital administration for suitable patients. These preferences encourage manufacturers to develop subcutaneous-compatible products, as formulation affects treatment settings and provider access. The SILVER Phase Ib study is evaluating low-dose subcutaneous IL-2 at 125,000 IU/kg with tebentafusp in uveal melanoma. The study demonstrates the growing use of subcutaneous IL-2 in newer combination regimens and can broaden access across the Interleukin-2 industry.

Complete Report Scope:

• By Product Type
  • Aldesleukin
  • Denileukin Diftitox
  • Engineered IL-2 Receptor Agonists
  • Pegylated IL-2 Products
  • IL-2 Fusion Proteins
  • Other IL-2 Products
• By Route of Administration
  • Intravenous
  • Subcutaneous
  • Others
• By Indication
  • Renal Cell Carcinoma
  • Melanoma
  • Hematological Cancer
  • Autoimmune Disease
  • Other Indications
• By End User
  • Hospitals and clinics
  • Academic Medical Centers and Research Institutes
  • Specialty Cancer Centers
  • Others
• By Geography
  • North America
    • United States
    • Canada
    • Mexico
  • Europe
    • Germany
    • United Kingdom
    • France
    • Italy
    • Spain
    • Rest of Europe
  • Asia-Pacific
    • China
    • India
    • Japan
    • Australia
    • South Korea
    • Rest of Asia-Pacific
  • Middle East and Africa
    • GCC
    • South Africa
    • Rest of Middle East and Africa
  • South America
    • Brazil
    • Argentina
    • Rest of South America

Geography Analysis

North America held 39.34% of the Interleukin-2 market revenue in 2025. The United States has FDA-approved Proleukin and LYMPHIR products, an expanding lifileucel treatment-center network, and academic centers that administer high-dose IL-2 and conduct clinical trials. Canada supports market access through its developing oncology reimbursement framework, while private oncology clinics are an important access route in Mexico. Europe benefits from an established oncology infrastructure and multinational clinical trial activity, led by Germany, France, and the United Kingdom. The European Medicines Agency reviewed Iovance's resubmitted marketing authorization application in 2026, supporting European access to TIL therapy.

Asia-Pacific is the fastest-growing region, with a projected CAGR of 8.45% during 2026-2031. China accounted for 40%-45% of Asia-Pacific demand in 2026, driven by recombinant human IL-2 use in oncology, public immunotherapy research investment, and low-dose autoimmune trials. A Phase IIb systemic lupus erythematosus study across 12 Chinese hospitals positioned China as a clinical evidence producer and treatment market. Japan and South Korea contributed 30%-35% of regional revenue, supported by REMITORO approval, manufacturing capacity, and biotechnology activity.

The Middle East, Africa, and South America remain smaller regional segments in the Interleukin-2 market. Saudi Arabia and the United Arab Emirates are expanding national oncology programs, although ICU requirements limit adoption in certain facilities. Brazil leads South American adoption through regulatory alignment and a growing private oncology sector. Reimbursement systems in both regions have not fully adapted to the cost structure of IL-2 combinations and adoptive cell therapy, favoring outpatient-compatible engineered and subcutaneous products over hospital-dependent aldesleukin regimens.

List of Companies Covered in this Report:

• Anaveon AG
• Ascendis Pharma A/S
• Asher Biotherapeutics, Inc.
• BioNTech
• Citius Pharmaceuticals, Inc.
• Corvus Pharmaceuticals, Inc.
• Cue Biopharma, Inc.
• Eisai
• Equillium, Inc.
• ILTOO Pharma
• Innovent Biologics, Inc.
• Iovance Biotherapeutics, Inc.
• Krystal Biotech, Inc.
• Medicenna Therapeutics Corp.
• Merck
• Mural Oncology plc
• Nektar Therapeutics
• Philogen S.p.A.
• Sanofi
• Synthekine, Inc.
• TILT Biotherapeutics Ltd
• Werewolf Therapeutics, Inc.
• Xilio Therapeutics, Inc.

Additional Benefits:

• The market estimate (ME) sheet in Excel format
• 3 months of analyst support