Interferon Research History: Discovery, Key Trials and Regulatory Timeline

Interferon is one of the oldest named cytokines in biology, and its research history runs in two directions: decades of work on giving interferon, followed by a newer line of work on blocking it. This page sets out what the published record describes, who identified the phenomenon, which studies and reviews mark the main turning points, and which regulatory milestones are documented in the indexed literature. This page is for educational purposes only and is not medical advice; consult a licensed physician for any question about diagnosis, treatment or medication. No doses, protocols or use guidance appear anywhere below.

Who discovered interferon, and when

Interferon was not purified first and explained later. It was inferred from an experiment. Working in London in the late 1950s, virologists Alick Isaacs and Jean Lindenmann observed that chick embryo chorioallantoic membranes exposed to heat-inactivated influenza virus released a soluble factor into the surrounding fluid, and that fresh tissue bathed in that fluid resisted subsequent infection by live virus. They named the factor for the effect it produced, viral interference, and the word interferon entered the literature in 1957.

That original report predates the verified citation set used on this page, so it is described here as historical attribution rather than as a sourced finding. Everything below that concerns a study result, a mechanism or a regulatory decision carries its own PubMed link in the same sentence.

The source material of early work

Early interferon was a biological preparation, not a defined molecule: it was whatever antiviral activity could be recovered from virus-exposed cells, initially avian membranes and later human leukocytes and fibroblasts. The field spent much of the 1960s and 1970s establishing that interferon was a protein, that species of origin mattered, and that more than one interferon existed. Molecular cloning in the late 1970s and early 1980s converted interferon from a scarce extract into a recombinant protein that could be manufactured and studied at scale, which is the technical change that made clinical trials practical.

Interferon as a therapeutic: the oncology trial era

The first large clinical programmes for recombinant interferon were in haematology and oncology. A 2019 review of cytokines in clinical cancer immunotherapy described interferon-α and interleukin-2 as the earliest cytokines brought into routine cancer care, and reported that their clinical use has been constrained by systemic toxicity and by narrow therapeutic windows when cytokines are administered at pharmacological levels (PMID 30413827). That same review framed later engineering efforts, fusion proteins, targeted delivery and combination strategies, as responses to the limitations the original interferon trials exposed (PMID 30413827).

Melanoma was the disease where interferon's adjuvant role was most visible and where it was most clearly superseded. A 2020 review of immuno-oncology in melanoma described interferon-alfa as part of the historical adjuvant landscape that was displaced by immune checkpoint inhibitors and targeted therapy as those agents accumulated evidence (PMID 32368174). The reviewers reported that the modern treatment algorithm in advanced melanoma is organised around checkpoint blockade rather than around cytokine administration (PMID 32368174).

In myeloproliferative neoplasms the trajectory was different, because interferon persisted rather than disappeared. A 2024 review of the evolving landscape of polycythemia vera therapies placed interferon-based agents alongside cytoreductive drugs and newer mechanisms in the treatment landscape it surveyed, and reported that the therapeutic options for the disease have broadened considerably in recent years (PMID 39106053).

Mechanism research: what interferon actually switches on

While clinical programmes ran, laboratory work moved from the phenomenon to the pathway. Interferons signal through dedicated receptors and induce a large family of interferon-stimulated genes, and much of the modern literature is about which of those gene products do the antiviral work.

The IFITM proteins are one well-studied example. A 2023 paper in Viruses described the discovery and characterisation of S-palmitoylation of interferon-induced transmembrane proteins, and reported that this lipid modification is a determinant of how IFITM proteins behave in membranes during antiviral restriction (PMID 38140570). The study is a useful marker of how far the field moved: from a soluble factor defined by an assay in 1957 to a named effector protein defined by a post-translational modification.

A second line of work asked what sets the baseline tone of the interferon system. A 2020 Cell study on commensal microbiota modulation of natural resistance to virus infection reported that signals from resident microbiota influenced host resistance to viral challenge, linking the composition of the microbial community to antiviral defence (PMID 33212011). Researchers in that study framed antiviral resistance as something that varies with host ecology rather than being fixed, which is a conceptual shift relative to the single-factor model of the 1950s (PMID 33212011).

The reversal: blocking interferon instead of supplying it

The most important recent chapter in interferon history is that the pathway became a drug target in the opposite direction. In several immune-mediated diseases, excess interferon signalling is the problem, and the agents that reached approval are antibodies that interrupt it.

Interferon-γ blockade in haemophagocytic lymphohistiocytosis

Emapalumab, a monoclonal antibody directed against interferon-γ, was described in a 2019 Drugs first-approval report as having received its first global approval in 2018 in the United States for primary haemophagocytic lymphohistiocytosis (PMID 30623346). That report summarised the development programme leading to the approval and the milestones recorded for the agent (PMID 30623346). A 2024 review in the Journal of Hematology & Oncology on current treatment advances in haemophagocytic lymphohistiocytosis discussed emerging targeted therapy and the underlying mechanisms of the hyperinflammatory state, including cytokine-directed approaches (PMID 39511607).

Type I interferon receptor blockade in lupus

Anifrolumab, a monoclonal antibody against subunit 1 of the type I interferon receptor, was described in a 2021 Drugs first-approval report as having received its first approval in 2021 for systemic lupus erythematosus (PMID 34554438). The report traced the agent's development through its clinical programme to that regulatory decision (PMID 34554438).

The interferon signature in dermatomyositis

A 2025 review on innovation in dermatomyositis in Dermatologic Clinics surveyed emerging therapeutic approaches for the disease and the mechanistic rationale behind them, in a condition where interferon-driven inflammation is a recognised feature (PMID 39542557). The authors reported that the therapeutic pipeline has expanded beyond conventional immunosuppression toward pathway-specific agents (PMID 39542557).

Documented regulatory timeline

The table below lists only milestones that appear in the verified citation set for this page, each with its PubMed link. It is not a complete regulatory history of every interferon product.

Adverse Events Across the Interferon Literature: What Studies Report

Interferon's tolerability profile shaped its clinical history as much as its activity did. The 2019 cytokine review reported that systemic administration of cytokines such as interferon-α in oncology has been limited by toxicity, which motivated engineering strategies intended to localise or modify cytokine exposure (PMID 30413827).

Dermatological reactions are a specific, well-documented category. A review of drug-induced psoriasis listed interferons among the agents reported to induce or exacerbate psoriasis, alongside other immunomodulatory and non-immunological drug classes, and reported that both new-onset and aggravated disease have been described in the literature (PMID 21489366). The authors discussed the latency between drug exposure and skin findings as a recurring difficulty in attributing causation (PMID 21489366).

On the blockade side, the first-approval reports for emapalumab (PMID 30623346) and anifrolumab (PMID 34554438) summarised the development and safety evaluation each agent underwent before approval; the full labelled safety information for any approved product sits with the regulator and the prescribing physician, not with an education page.

How the chronology reads overall

1. Phenomenon (1957). Viral interference in chick embryo membranes gave the molecule its name.
2. Characterisation and cloning (1960s-1980s). Interferon was established as a protein family and then produced recombinantly, enabling trials.
3. Clinical cytokine era. Interferon-α entered cancer immunotherapy as one of the first cytokines in routine use, with toxicity as the limiting factor reported in review (PMID 30413827).
4. Displacement and persistence. Checkpoint inhibitors reorganised melanoma care away from cytokine adjuvant therapy (PMID 32368174), while interferon-based agents remained part of the polycythemia vera landscape (PMID 39106053).
5. Mechanistic depth. Interferon-stimulated effectors such as IFITM proteins were characterised at the level of lipid modification (PMID 38140570), and host microbiota were linked to natural antiviral resistance (PMID 33212011).
6. Pathway blockade (2018-2021). Emapalumab (PMID 30623346) and anifrolumab (PMID 34554438) reached first approval as interferon-pathway antagonists, with interferon-directed strategies also discussed for haemophagocytic lymphohistiocytosis (PMID 39511607) and dermatomyositis (PMID 39542557).

Related reading: Interferon: what the literature describes.

References

• Cytokines in clinical cancer immunotherapy (British Journal of Cancer, 2019)
• Use of immuno-oncology in melanoma (Current Oncology, 2020)
• The evolving landscape of polycythemia vera therapies (Expert Opinion on Pharmacotherapy, 2024)
• Discovery and Characterization of IFITM S-Palmitoylation (Viruses, 2023)
• Commensal Microbiota Modulation of Natural Resistance to Virus Infection (Cell, 2020)
• Emapalumab: First Global Approval (Drugs, 2019)
• Hemophagocytic lymphohistiocytosis: current treatment advances, emerging targeted therapy and underlying mechanisms (Journal of Hematology & Oncology, 2024)
• Anifrolumab: First Approval (Drugs, 2021)
• Innovation in Dermatomyositis (Dermatologic Clinics, 2025)
• Drug induced psoriasis (Acta Dermatovenerologica Croatica, 2011)