Skip to content
ContentLora

    Tip: press / anywhere to search.

    technology

    Personalised mRNA neoantigen vaccines

    Also known as individualised neoantigen therapy, INT, mRNA cancer vaccines, intismeran autogene, mRNA-4157, V940, autogene cevumeran, BNT122

    Personalised neoantigen vaccines are mRNA therapies designed for each patient from their tumour's mutations.[1] In August 2026 Merck and Moderna's intismeran autogene plus Keytruda met its phase 3 endpoints in resected melanoma, while BioNTech ended a colorectal trial of its rival vaccine the same month.[2][3]

    Editor reviewedStrict sourcingUpdated Cancer immunotherapyHealth and medicineLife sciences
    Key facts

    Personalised neoantigen vaccines, also called individualised neoantigen therapies, are cancer treatments built for one patient at a time. Each is a synthetic mRNA encoding neoantigens selected from that patient’s tumour; Merck and Moderna‘s intismeran autogene encodes up to 34.[1] The basics are covered in the explainer How cancer vaccines work, and the delivery technology in lipid-nanoparticle-delivery. The leading candidate has its own page, intismeran-autogene.

    Intismeran autogene (Merck and Moderna)

    In the randomised phase 2b KEYNOTE-942 trial, 157 patients with resected melanoma received mRNA-4157 plus pembrolizumab or pembrolizumab alone; recurrence-free survival was longer with the combination (hazard ratio 0.561), with 18-month recurrence-free survival of 79% versus 62%.[4] It was a modest-sized phase 2b trial, and the difference had a two-sided p value of 0.053. Most treatment-related side effects were grade 1-2; grade 3 or higher events occurred in 25% of the combination group and 18% with pembrolizumab alone, with no grade 4-5 events attributed to the vaccine.[5] On 19 August 2026 the companies announced that the phase 3 INTerpath-001 trial, with 1,137 patients with resected stage IIB-IV melanoma, met its primary endpoint of recurrence-free survival and key secondary endpoint of distant metastasis-free survival.[2] They reported no new safety signals and plan to present the data and engage regulators on filings.[6]

    Autogene cevumeran (BioNTech and Genentech)

    In a 16-patient pancreatic cancer study, autogene cevumeran given with atezolizumab induced neoantigen-specific T cells in 8 patients, whose recurrence-free survival was longer than non-responders’.[7] Follow-up estimated those vaccine-induced CD8+ T-cell clones live 7.7 years on average.[8] A phase 1 trial across solid tumours found neoantigen-specific responses in 71% of patients.[9] But on 28 August 2026 BioNTech ended a phase 2 trial of the vaccine alone in resected colorectal cancer after its data monitoring board saw a numerical overall-survival imbalance; the pancreatic combination trial IMcode003 continues.[3]

    Other 2026 data

    A February 2026 Nature paper reported 14 patients with triple-negative breast cancer who received an individualised neoantigen mRNA vaccine after surgery and standard therapy. Vaccine-induced T-cell responses remained functional for years, and 11 patients stayed relapse-free for up to six years.[10] The study had no control group, so it shows immune activity and feasibility rather than benefit.[10]

    Not every neoantigen vaccine is made per patient. Nous-209 encodes 209 frameshift neoantigens shared across tumours with mismatch-repair defects.[11] In a January 2026 Nature Medicine trial in 45 people with Lynch syndrome, a hereditary cancer syndrome, it caused no intervention-related serious adverse events and induced neoantigen-specific responses in all 37 evaluable participants, still detectable at one year in 85%. The trial measured safety and immune responses, not whether cancers were prevented.[11]

    Reading the evidence

    The two programmes differ in partner drug and setting: the melanoma success paired the vaccine with a checkpoint inhibitor, while the stopped colorectal trial tested the vaccine as monotherapy.[2][3] The pancreatic responder analysis is not a randomised comparison.[7] INTerpath-001 effect sizes were not public at the time of the announcement.[6]

    Questions readers ask

    Is a personalised mRNA cancer vaccine approved?

    Not as of October 2026. After the positive phase 3 INTerpath-001 readout in August 2026, Merck and Moderna said they would engage regulators on filings.[2][6]

    What did the phase 3 melanoma trial show?

    Intismeran autogene plus Keytruda improved recurrence-free survival and distant metastasis-free survival versus Keytruda alone in 1,137 patients with resected stage IIB-IV melanoma, with no new safety signals reported. Effect sizes had not been published at announcement.[2][6]

    Why was the colorectal trial stopped?

    BioNTech said its data monitoring board saw a numerical imbalance in overall survival between arms and judged that continuing was unlikely to change the efficacy outcome.[3]

    Do neoantigen vaccines have to be personalised?

    Not always. Nous-209 is an off-the-shelf vaccine encoding 209 neoantigens shared across mismatch-repair-deficient tumours; in a 2026 trial in Lynch syndrome carriers it induced immune responses in all 37 evaluable participants.[11]

    Sources

    Each numbered claim is a statement we checked against the sources listed with it. Status shows how well established it is.

    1. [1]

      Intismeran autogene (mRNA-4157/V940), co-developed by Merck and Moderna, is an individualised mRNA therapy encoding up to 34 neoantigens chosen from each patient's tumour. confirmedas of 2026-08-19

    2. [2]

      Merck and Moderna announced on 19 August 2026 that the 1,137-patient phase 3 INTerpath-001 trial of intismeran autogene plus Keytruda in resected stage IIB-IV melanoma met its primary endpoint of recurrence-free survival and key secondary endpoint of distant metastasis-free survival versus Keytruda alone. confirmedas of 2026-08-19

    3. [3]

      On 28 August 2026 BioNTech ended a phase 2 trial of autogene cevumeran monotherapy in resected colorectal cancer after its data monitoring board saw a numerical overall-survival imbalance between arms; the pancreatic cancer trial IMcode003 continues. confirmedas of 2026-08-28

    4. [4]

      In the randomised phase 2b KEYNOTE-942 trial of 157 patients with resected melanoma, mRNA-4157 plus pembrolizumab lengthened recurrence-free survival versus pembrolizumab alone (hazard ratio 0.561), with 18-month recurrence-free survival of 79% versus 62%. confirmedas of 2024-02-01

    5. [5]

      In KEYNOTE-942, most treatment-related adverse events were grade 1-2; grade 3 or higher treatment-related events occurred in 25% of the combination group and 18% with pembrolizumab alone, with no grade 4-5 events attributed to mRNA-4157. The recurrence-free survival difference had a two-sided p value of 0.053. confirmedas of 2024-02-01

    6. [6]

      Merck and Moderna reported no new safety signals in INTerpath-001 and said they plan to present the data at a medical meeting and engage regulators on filings; full results had not been published as of the announcement. confirmedas of 2026-08-19

    7. [7]

      In a 16-patient pancreatic cancer study, the individualised mRNA vaccine autogene cevumeran induced new neoantigen-specific T cells in 8 patients, and these responders had longer recurrence-free survival than non-responders (median not reached vs 13.4 months). confirmedas of 2023-06-01

    8. [8]

      A 2025 follow-up estimated that vaccine-induced CD8+ T-cell clones in pancreatic cancer responders had an average lifespan of 7.7 years. confirmedas of 2025-03-01

    9. [9]

      In a phase 1 trial across advanced solid tumours, autogene cevumeran induced neoantigen-specific T-cell responses in 71% of patients. confirmedas of 2025-01-01

    10. [10]

      In a 2026 Nature report on 14 patients with triple-negative breast cancer given an individualised neoantigen mRNA vaccine after standard treatment, vaccine-induced T-cell responses persisted for years and 11 patients remained relapse-free for up to six years; the study had no control group. confirmedas of 2026-02-18

    11. [11]

      In a 2026 phase 1b/2 trial in 45 people with Lynch syndrome, a hereditary cancer syndrome, the off-the-shelf neoantigen vaccine Nous-209, which encodes 209 frameshift neoantigens shared across mismatch-repair-deficient tumours, caused no intervention-related serious adverse events and induced neoantigen-specific immune responses in all 37 evaluable participants, still detectable at one year in 85%. confirmedas of 2026-01-16

    Revision history (2)
    1. Page created.
    2. Refresh: added the 2026 Nature TNBC individualised mRNA vaccine study, the off-the-shelf Nous-209 vaccine, and links to related vaccine pages.

    Created Oct 10, 2026. Last reviewed by an editor on Oct 10, 2026. Next scheduled review: Jan 10, 2027.

    Cite this page

    "Personalised mRNA neoantigen vaccines." ContentLora, updated Oct 10, 2026. https://contentlora.com/wiki/personalized-neoantigen-vaccines

    Spotted an error? Suggest a correction or emailcorrections@contentlora.com.

    Keep exploring

    Connections
    Immune checkpoint i… Combined with
    ☰ Contents