A data-driven cartography of NSCLC vaccine research: Quantifying the paradigm shift toward immuno-oncology combination therapies.

Introduction
Non-small cell lung cancer (NSCLC), accounting for approximately 85% of lung cancers, has undergone a therapeutic paradigm shift from conventional modalities to targeted and immune-based strategies. Among immunotherapeutic approaches, cancer vaccines have emerged as a key focus of investigation, although they remain largely experimental and have yet to achieve widespread clinical adoption.1 The field originated in the 1990s with foundational breakthroughs in tumor immunology, initially focusing on the identification and validation of tumor-associated antigens (TAAs) such as MUC1 (Mucin 1), HER2 (Human Epidermal Growth Factor Receptor 2), and C-kit (CD117).2–5
Early vaccine platforms were technologically straightforward, typically employing whole-tumor-cell lysates or single antigen peptides. Foundational clinical studies from this period, including a 1995 trial demonstrating the induction of anti-epidermal growth factor antibodies and a 2001 trial (NCT00023985) confirming the safety and immunogenicity of a dendritic cell (DC) vaccine, established crucial proof-of-concept for immunogenicity rather than clinical efficacy.6,7
The 2000s marked a transition toward multi-antigen formulations and their use in adjuvant settings, with numerous trials investigating vaccines against specific targets, including EGFR (Epidermal Growth Factor Receptor) mutations.8 However, the 2010s represented a critical inflection point. Research shifted toward tumor-specific antigens, with large-scale clinical trials focusing on vaccines targeting MAGE-A3 and New York esophageal squamous cell carcinoma 1 (NY-ESO-1). Critically, these trials failed to demonstrate a significant survival benefit as monotherapies.9,10 These outcomes clearly demonstrated that overcoming the profound immune tolerance of established tumors necessitates a multi-pronged, synergistic approach, thereby establishing the rationale for combination therapy as the prevailing paradigm.
Contemporary research centers on the strategic combination of cancer vaccines with other therapeutic classes. Synergistic regimens combining vaccines with ICIs, such as anti-PD-1/PD-L1 (Programmed cell death protein 1/Programmed death-ligand 1) antibodies, are being explored to enhance antitumor immune responses and overcome resistance mechanisms.11,12 Concurrently, advances in genomic technologies have fueled the development of personalized vaccines. By leveraging next-generation sequencing to identify patient-specific neoantigens, tailored vaccines can be designed to elicit highly targeted immune responses, a precision strategy currently under evaluation in early-phase clinical trials.13,14 This era is also marked by the rapid development of novel delivery platforms, particularly messenger RNA (mRNA) technology, whose flexibility and rapid manufacturing capabilities position it as a transformative modality for NSCLC immunotherapy.15
The developmental history of NSCLC vaccines reflects the complex scientific challenges inherent in tumor immunotherapy. The trajectory from single-antigen designs to integrated, multi-target strategies reflects a progressively deeper understanding of three core requirements for efficacy: optimal antigen selection, potent adjuvant formulation, and comprehensive modulation of the tumor immune microenvironment.16,17 The failure of early monotherapies such as the MAGE-A3 vaccine provided invaluable insights, revealing that tumor heterogeneity demands broader antigen coverage, while the immunosuppressive Tumor Microenvironment (TME) must be actively remodeled. Indeed, emerging nanovaccine platforms are being engineered to co-deliver antigens and immunomodulators to address these limitations synergistically.18 Future progress in the field is expected to advance along three primary axes. First, the integration of artificial intelligence will refine neoantigen prediction, enhancing the precision and efficiency of personalized vaccine manufacturing.19 Second, research will focus on optimizing multimodal regimens to define the ideal sequencing and combination of vaccines with ICIs, chemotherapy, and targeted agents. Third, vaccines will be explored in early-stage NSCLC as an adjuvant therapy to prevent recurrence. As mRNA platforms mature and immune regulatory are further elucidated, NSCLC vaccines are poised to transition from an experimental concept to a standard-of-care component, fundamentally shifting the treatment goal from targeted cytotoxicity to durable, immune-mediated cure.20,21

Materials and methods

Database and search strategy
Bibliographic data were retrieved on September 6, 2025, from the Web of Science (WoS) Core Collection and Scopus databases. The search strategy integrated keywords pertaining to “vaccines” (e.g., “cancer vaccine,” “mRNA vaccine,” “neoantigen vaccine”) and “non-small cell lung cancer” (e.g., “NSCLC,” “lung adenocarcinoma”). Detailed search queries for both databases are provided in Supplementary Material S1. The initial retrieval yielded 1216 records from WoS and 2638 records from Scopus. Two reviewers independently screened the records based on titles, abstracts, and document types (restricted to articles and reviews published in English), resolving any discrepancies through consensus. This process established a preliminary dataset comprising 493 publications from WoS and 568 from Scopus (Figure 1).

Data processing and standardization
To guarantee the robustness of the bibliometric analysis, we implemented a rigorous data processing protocol to address database heterogeneity and formatting inconsistencies. The raw datasets from WoS and Scopus underwent a multi-step standardization process: (1) Manual verification and cross-database deduplication: A hybrid approach combining the automated similarity matching tool TeslaSCI22 and manual verification was employed to harmonize records, eliminating duplicates while preserving unique contributions from both databases. (2) Field normalization: Key metadata from Scopus – including author names, affiliations, references, publication years, and unique identifiers – were standardized. Scopus citation formats were parsed and converted to align with WoS standards, achieving a conversion rate of 98.4%. (3) Entity disambiguation and thesaurus normalization: A custom standardized thesaurus was constructed to merge lexical variants of keywords, institutions, and author names, ensuring semantic consistency and accuracy. This process ultimately generated a high-quality analysis corpus comprising 765 publications. Technical details regarding cleaning algorithms, validation protocols, and thesaurus construction are provided in Supplementary S2.

Analytical methods
Temporal growth trends in the field were analyzed using Python. Network visualization and structural analyses were conducted using VOSviewer (v1.6.20) and CiteSpace (v6.4.R1).23 VOSviewer was primarily employed to map collaboration networks (countries, institutions, authors) and keyword co-occurrence networks, while CiteSpace was utilized for time-series analysis and burst detection to identify emerging trends. Geographic distributions were visualized using Tableau Public and Scimago Graphica. An alluvial diagram was generated to illustrate citation flows between journals.24 To ensure consistency, a unified master thesaurus and stop-word list were applied across all analytical platforms; detailed parameters are presented in Supplementary Material S3.

Results

Analysis of the number of publications and citations
A systematic bibliometric analysis of 765 publications was conducted to map the scholarly landscape over a 35-year period (Figure 2). The results reveal a significant growth trend and a distinct developmental trajectory. Annual publication volume demonstrates a strong temporal correlation (R2 = 0.7669, P < .001), with an average increase of 6.31 publications per year (Table 1). The evolution of this field can be characterized by three phases: an initial exploratory period, a subsequent phase of rapid expansion, and a recent stage of high-volume output. Notably, productivity peaked in 2024, suggesting that the field is currently in a highly active state.

Citation volume also exhibits a significant positive trend over time (R2 = 0.3548, P < .001), with an average annual increase of 194.83 citations. However, the lower coefficient of determination (R2) suggests greater temporal variability in citation counts compared to publication output, likely reflecting more complex citation dynamics. Of note, these citation metrics are based on internal references within the analyzed corpus. Pearson correlation analysis revealed a moderate positive relationship between publication and citation counts (r = 0.5045), which aligns with established bibliometric principles. The moderate strength of this correlation implies that factors beyond mere publication volume – such as research quality, evolving research hotspots, and journal impact – are significant determinants of citation impact. Based on these publication patterns, the field appears to have transitioned from an emerging discipline to a mature stage of development. The accumulation of 765 publications, combined with the current high-output state, suggests that the field may be approaching a saturation point.

Analysis of contributions of prolific and co-cited authors
The scholarly collaboration network in this domain displays a characteristic “small-world” topology, featuring multiple interconnected academic communities that are internally cohesive and led by core authors.
A research group headed by the Cuban scholar Tania Crombet Ramos constitutes a particularly prominent cluster (Table 2, Figure 3(A–D)). This team, which includes Elia Neninger Vinageras and Carmen Viada, forms a highly cohesive sub-network. Tania Crombet Ramos has authored 19 publications and achieved an average of 41.16 citations per paper, underscoring the team’s sustained influence and central role. The American scholar John Nemunaitis represents another pivotal node in the network. Nemunaitis is distinguished by a high average citation rate of 80.75 per paper and an H-index of 11. With 8 publications as corresponding author, he is among the most academically influential figures in this field (Table 3).

In terms of academic impact, John Nemunaitis and the Canadian researcher Butts C. are particularly noteworthy. Although Butts C. has only four publications as corresponding author, one seminal work – a Phase IIB randomized trial of the BLP25 liposome vaccine – has amassed 715 citations, highlighting the breakthrough nature of this study. This distinction between collaborative breadth and impactful depth delineates a stratified research landscape, comprising extensive collaborators, prolific authors, and scientists who have produced exceptionally high-impact work.
A temporal analysis reveals a distinct three-stage evolutionary trajectory for the field: a foundational period (1987–2000), a period of expansion (2001–2015), and a period of succession (2016–present) (Figure 3(E)). During the foundational stage, the intellectual landscape was shaped by a small cohort of pioneers, including Turner M.I. and Schulof R.S. Subsequently, the field entered a phase of rapid expansion, wherein scholarly influence became more distributed among central figures such as John Nemunaitis and Luis E Raez. Over the past decade, a significant generational succession has occurred, shifting the nexus of influence to a new cohort of academic leaders, including Spigel D.R. and Kroemer M. This trajectory not only reflects the growth and maturation of the research community but also mirrors a fundamental paradigm shift – from early, foundational vaccine research to the current, more complex stage characterized by neoantigens, combination immunotherapies, and precision-based strategies.
The co-cited author network demonstrates a “core-periphery” structure comprising several tightly-knit communities centered on key scholars such as Butts, C., Nemunaitis, J., Rosenberg, SA, and Sahin, U. (Table 4). These core authors serve as intellectual hubs, anchoring the production and exchange of knowledge. Meanwhile, researchers such as Reck, M. function as “bridge” authors, connecting disparate research groups and facilitating knowledge integration (Figure 4(A–C)). The temporal evolution of the field’s intellectual foundations (Figure 4(D)) shows a transition from an early reliance on a few key scholars (e.g., Brinckerhoff, CE) to a highly diversified knowledge base after 2008. The growing influence of emerging researchers (e.g., Smith, AB) indicates a deepening and diversification of the research frontier into multiple sub-fields. Analysis of collaborator data (Table 2) confirms that central figures in the collaboration network are also the most frequently cited authors, positioning them as dual leaders in the field’s social and intellectual architecture. Their representative works have defined the dominant paradigms in this domain: (1) tumor vaccines, represented by Butts, C.; (2) PD-L1 immune checkpoint inhibitors, represented by Reck, M.; and (3) personalized neoantigen vaccines, represented by Sahin, U. Consequently, the collaborative communities function as “thought collectives” organized around these pivotal research directions. In summary, the field is predominantly steered by elite scholars from North America and Europe, whose efforts have collectively shaped the entire knowledge landscape, from conventional therapies to pioneering personalized immunotherapy.

Analysis of the journal co-citation
The network is organized into three primary clusters: a clinical medicine cluster anchored by the New England Journal of Medicine; a basic biomedical science cluster centered on Nature, Science, and Cell; and a specialized immunology and molecular biology cluster (Figure 5(A–C)).

Temporal analysis of journal impact demonstrates a clear evolutionary trajectory (Figure 5(D)). The early period (1987–1994) was dominated by traditional oncology journals like the European Journal of Cancer and Clinical Oncology, reflecting a concentrated disciplinary landscape. Subsequent periods (1995–2010) were marked by significant diversification, with biotechnology and molecular biology journals such as Gene and the International Journal of Biological Markers gaining prominence. The most recent stage (2011–2025) is characterized by high interdisciplinarity, with a sharp increase in the influence of immuno-oncology publications and a relative decline of single-discipline periodicals. The emergence of journals related to regulatory science and bioinformatics signifies a critical shift in focus from basic research toward clinical translation.
The distribution of journal influence follows a core-periphery structure consistent with Bradford’s Law, wherein a few core journals dominate academic discourse (Figures 5 and 6(A)). This hierarchy is visualized by node size, which corresponds to citation frequency; top-tier journals like Nature, Science, Cell, and the New England Journal of Medicine form the largest nodes (Figure 6(B)). Notably, a disparity exists between global and local citation impact. The specialized journal Molecular Cancer, for instance, surpasses generalist journals like Nature in global citation counts, whereas the Journal of Clinical Oncology holds a dominant position within the local citation network. This highlights functional specialization: the former represents the field’s cutting-edge research front, while the latter constitutes its foundational knowledge base.

A dual-map overlay of journals visually substantiates this structure (Figure 6(C)). The map illustrates two primary knowledge-flow pathways: a yellow trajectory representing vertical inheritance of knowledge within molecular biology, and a green trajectory illustrating horizontal translation of knowledge from basic health and medical sciences into clinical applications. These pathways reveal that the field is propelled by a dual engine: the deepening of basic research and its convergence with clinical practice. This finding precisely corroborates the functional division between the basic research (green cluster) and clinical research (red cluster) domains identified in the co-citation network analysis.

Analysis of institutional contributions
Analysis of the global collaboration network reveals a multipolar, hierarchical structure centered on the United States, with Europe serving as a major fulcrum and Asia as a prominent emerging force. Institutional influence is a multifactorial construct, extending beyond publication volume to encompass network centrality and per-publication impact (Figure 7(A–E)). For example, while the NIH leads in publication output, Assistance Publique-Hôpitaux de Paris functions as a pivotal network hub due to its high connectivity. Notably, institutions such as Harvard University and the Dana-Farber Cancer Institute, despite modest publication volumes (n = 13 each), exhibit disproportionately high local citation counts (317 and 222, respectively). This underscores their substantial academic influence, amplified through high-impact research. This stratification of institutional influence aligns with findings from the journal analysis. The academic ecosystem is driven by key actors (institutions and journals) with distinct functional roles. Some, like Assistance Publique-Hôpitaux de Paris and the Journal of Clinical Oncology, serve as “stable cornerstones” of the knowledge system, characterized by high connectivity and local citations. In contrast, others, such as Harvard University and Molecular Cancer, function as “innovative frontiers,” shaping the field’s trajectory through high-impact publications.

Sankey diagram analysis reveals knowledge-flow pathways connecting core authors, leading institutions, and principal countries (Figure 8(A)). The United States maintains a dominant position, supported by a diverse institutional matrix that includes both traditional academic powerhouses (e.g., NIH, Harvard University, University of California system) and specialized research centers (e.g., Memorial Sloan Kettering Cancer Center, The University of Texas system). French institutions, including INSERM, Paris-Saclay University, Université Paris Cité, and Assistance Publique-Hôpitaux de Paris, constitute a distinct research cluster that maintains strong ties with US counterparts, indicative of highly integrated transatlantic collaborative. Concurrently, Asian institutions, exemplified by the Chinese Academy of Medical Sciences, are emerging as key nodes in the global network. The temporal trajectory of the network delineates a clear maturation process for the field (Figure 8(B)). This evolution progressed from an early, US-centric network to broader international collaboration involving governmental and industrial entities (e.g., FDA, Novartis), culminating in the present-day global, diverse, and highly specialized collaborative innovation network. The period between 2015 and 2025 is characterized by even greater complexity and differentiation. The sustained engagement of newly prominent specialized institutions, such as the Vall d’Hebron Institute of Oncology, Montpellier University Hospital, the University of Padua, and the University of Edinburgh, indicates a paradigm shift in the global cancer research landscape toward increased specialization, networking, and collaboration.

Analysis of country contributions
The international scientific collaboration landscape is characterized by a markedly uneven distribution of publication output and network influence (Figure 9(A–C)). The United States is the clear core of the network, leading in publication volume (n = 276), degree centrality (33), and betweenness centrality (0.36). These metrics establish its position as a “super-hub” with dominant control over knowledge production and flow. In contrast, China ranks second in publication output (n = 150) but exhibits comparatively modest network influence, with a degree centrality of 18 (10th) and a betweenness centrality of 0.08 (9th). This disparity between its status as an “output giant” and its role as a “network intermediary” suggests that China’s integration into the global system relies more on connections to core nodes than on functioning as an independent regional hub. Conversely, European nations exhibit a strong network advantage. Countries such as Germany (n = 47), France (n = 63), and Spain, despite lower publication volumes than the US and China, possess degree centralities (30, 27, and 28, respectively) and betweenness centralities (e.g., Germany at 0.19, 2nd) that significantly surpass their output-based rankings. These metrics reflect a multicentral, highly efficient, and collaborative model fostered by European scientific integration. Further analysis identifies nations whose strategic network roles are disproportionate to their publication volumes. For instance, Switzerland (n = 47) ranks third in betweenness centrality (0.16), functioning as a critical “bridge” between distinct scientific blocs. Notably, Cuba plays a unique role in linking Latin American research with global networks. With 37 publications, it holds a betweenness centrality of 0.10. Its strategic importance, despite modest publication volume, is underscored by the presence of five Cuban authors among the top 10 collaborators (Table 2).

From a dynamic perspective, the international landscape is undergoing continuous evolution. The historical dominance of traditional scientific powers is being reshaped by the ascent of emerging economies, particularly in Asia (Figure 10(A,B)). This trend, combined with sustained investment from established scientific leaders and the strengthening of cross-regional collaborations, is collectively driving the field toward a more balanced and pluralistic global structure.

Analysis of highly references
Co-citation analysis of references in NSCLC immunotherapy reveals a multicentric knowledge base organized around pivotal theories and multiple parallel technological trajectories (Figure 11(A–C)). The theoretical cornerstone of this network is the 1993 study by Dranoff G on tumor vaccines engineered with granulocyte-macrophage colony-stimulating factor (GM-CSF), which, with the highest betweenness centrality, functions as the principal knowledge hub.25 Two primary research lineages diverge from this core. The first is a liposome vaccine branch, exemplified by the work of Butts C, whose 2005 paper is the most cited reference with 100 local and 390 global citations.26 The second is a gene-modified tumor cell vaccine branch centered on Nemunaitis J, whose 2006 publication (79 local, 315 global citations) was the first to apply transforming growth factor-beta 2 antisense gene-modified technology to lung cancer treatment27 (Table 5). This structure delineates the foundational knowledge framework of the field.

Cluster analysis further illuminates the evolution of the field’s knowledge structure and thematic progression (Figure 11(D)). The largest cluster, #0 “anti-cancer strategy” (N = 928, silhouette = 0.87), constitutes the foundational knowledge spectrum. Within this cluster, a highly cited 2011 review by Bremnes RM on the TME reflects a paradigm shift toward systemic immune regulation.28 Clusters #2 “innovative treatment” and #3 “novel method” represent continuous iteration of therapeutic strategies. Cluster #2 is dominated by early vaccine technologies, while #3 focuses on the integration of molecularly targeted and personalized approaches, tracing a trajectory from empirical treatment to precision medicine. Highly cohesive clusters, such as #8 “cell vaccine” (silhouette = 0.971), indicate that specific technological trajectories have matured into distinct knowledge sub-domains. Crucially, cluster #9, “exclusion checkpoint,” reflects how the advent of ICIs prompted cognitive restructuring of the role of traditional vaccine therapies. This shift catalyzed a paradigmatic transformation from monotherapy to combination strategies involving vaccines and ICIs.
The evolutionary trajectory of the field’s knowledge base, quantitatively validated by citation burst analysis, exhibits distinct phases (Figure 12(A–C)). The foundational period (1993–2010) was defined by the sustained citation burst of Dranoff G (1993) (strength 9.92, duration until 2009) and the long-term impact of Palmer M (2001), which collectively established the theoretical framework for tumor immunotherapy.25,29 The subsequent period of technological diversification (2005–2015) was characterized by hotspots in clinical exploration of vaccine technologies. This is evidenced by a series of high-intensity citation bursts, including studies on liposome vaccines by Butts C (2005; strength 17.32), gene-modified cell vaccines by Nemunaitis J (2006; strength 16.09), and protein vaccines by Vinageras EN (2008; strength 13.83), marking a peak of technology-intensive research.26,27,30 A revolutionary turning point occurred in 2012 with landmark publications on PD-1/PD-L1 inhibitors by Topalian SL (2012) and Lynch TJ (2012), which achieved historic citation burst strengths of 19.55 and 19.31, respectively.31,32 These studies, which first systematically reported the safety and efficacy of an anti-PD-1 antibody across multiple tumor types, catalyzed the rapid development of ICIs and fundamentally reshaped the therapeutic landscape. In the current era of precision immunotherapy (2015–present), citation patterns have shifted toward mature application of ICIs, as represented by papers from Borghaei H (2015) and Brahmer J (2015).33,34 The citation bursts for these works are more moderate in strength but longer in duration (extending to 2025), reflecting the transition of ICIs from breakthrough discovery to clinical optimization and established use. Concurrently, studies on personalized tumor vaccines by Sahin U (2017) and Ott PA (2017) are exhibiting nascent citation growth, heralding personalized immunotherapy as the next research frontier.35,36

Keyword analysis
Analysis of keywords identifies “immunotherapy” (365 citations), “non-small cell lung cancer” (NSCLC, 351 citations), and “vaccines” (321 citations) as the three most prominent research themes (Figure 13(A–C)). These are followed in frequency by “lung cancer,” “cancer immunotherapy,” “dendritic cell” (DC), and “melanoma.” Collectively, these high-impact keywords delineate the principal focus of the field: the application of immunological strategies, including vaccines and cell therapies, to treat solid tumors, with particular emphasis on NSCLC. The intellectual architecture of the field is characterized by several large, foundational clusters alongside numerous smaller, highly specialized frontier clusters (Figure 13(D)). The largest clusters, such as #0 “non-small cell lung cancer” and #1 “phase IIb trial,” encompass the most highly cited keywords, including “immunotherapy,” “NSCLC,” and “cancer immunotherapy,” thereby representing the core body of literature in established, high-volume research areas. Notably, research on “mRNA vaccine; current status” also constitutes a core research topic, distinguished by its large scale and high silhouette value, signifying substantial theoretical and practical maturity37 (Figure 14(A)).

Thematic evolution analysis demonstrates a clear three-phase trajectory: dispersion, integration, and subsequent redifferentiation (Figure 14(B)). In the early period (pre-2005), research themes such as “DC” and “cancer-testis antigen” were relatively dispersed. During the intermediate period (c. 2006–2017), these disparate themes converged into two principal knowledge streams” – immunotherapy” and “chemotherapy” – marking the initial consolidation of the field. In the recent period (2018–present), the dominant “cancer immunotherapy” stream has undergone rapid redifferentiation, spawning numerous highly specialized and cohesive frontier research clusters, as evidenced by their high silhouette values. These emergent clusters align directly with contemporary research hotspots: Neoantigen and vaccine technology clusters: These include #5 “neoepitope vaccine,” #6 “multiepitope peptide vaccine,” #9 “tumor cell” (containing “mRNA vaccine”), and #17 “STING agonist,” which focuses on the STING pathway. Despite their smaller size, these clusters exhibit exceptional internal cohesion (silhouette values typically ranging from 0.8 to 0.9) and represent highly innovative niche frontiers, consistent with their classification as “specialized themes” in the strategic coordinate diagram (Figure 14(C,D)). ICI clinical application clusters: Clusters #11 “advanced NSCLC” and #12 “NSCLC” feature core members such as “immune checkpoint inhibitors” and specific drugs like “pembrolizumab” and “nivolumab.” This progression suggests that ICI research has matured to encompass detailed investigations into specific clinical scenarios, drug selection protocols, and efficacy assessments.38 Molecular mechanism and targeted therapy clusters: Cluster #14, “RAS mutant tumor model,” centers on specific genetic mutations and targeted strategies, reflecting deepening research into fundamental molecular biology mechanisms.
Citation burst analysis of keywords illuminates the evolution of research frontiers and hotspots. The historical trajectory of the field reveals a paradigm shift from conventional therapies toward next-generation immunotechnologies (Figure 15(A,B)). Keywords with the highest burst strength pertain primarily to the maturation of clinical trials and exploration of specific technologies. The strong bursts for terms such as “phase ii” (burst strength 18.99), “double blind” (11.85), and “clinical trial” (11.87) underscore the field’s emphasis on clinical translation and evidence-based medicine. Concurrently, the intense burst for a specific technological avenue like “blp25 liposome vaccine” (18.27) chronicles the intense focus on a particular research direction during a specific period, although this approach did not ultimately achieve widespread adoption39 (Figure 15(C)). From a temporal perspective (Figure 15(C,D)), early research frontiers centered on conventional treatments and adjunctive therapies, such as “chemotherapy” and “colony stimulating factor”; however, citation bursts for these topics have since ceased. Conversely, contemporary research frontiers are dominated by emerging themes with ongoing citation bursts, most notably “immune checkpoint inhibitor” and “rna vaccine.” The prominence of these topics, coupled with the emergence of “1st line treatment” as a research hotspot, indicates that next-generation immunotherapies have transitioned from exploratory concepts to integral components of clinical practice, actively reshaping the standard of care in cancer treatment.40,41

Discussion
Over the past two decades, the therapeutic landscape for NSCLC has undergone a fundamental transformation.42 This paradigm shift is reflected in the 2025 updates to the American Society of Clinical Oncology (ASCO) and European Society for Medical Oncology (ESMO) guidelines, which incorporate findings from recent landmark trials to further refine precision treatment pathways.43,44 Consequently, the conventional “one-size-fits-all” approach, historically based on histological subtypes, has been supplanted by a new era of highly stratified, biomarker-driven precision medicine.45
This evolution is predicated on an enhanced understanding of tumor molecular biology, particularly the identification of Actionable Genomic Alterations (AGAs) – genetic drivers that have reshaped the therapeutic algorithm for NSCLC. The central tenet of modern NSCLC management is the transition from histopathological classification to an individualized strategy centered on molecular profiling. Accordingly, comprehensive molecular profiling at diagnosis is now the standard of care recommended by major international guidelines for all patients with advanced or metastatic disease. The identification of specific AGAs, which are genetic targets that promote tumor growth and proliferation, is essential for implementing optimized treatment regimens.46 For instance, mutations, rearrangements, or amplifications in genes such as EGFR, ALK, ROS1, BRAF, MET, RET, NTRK, NRG, KRAS, and ERBB2 are integral to determining patient treatment options and prognosis.42,47 It is also noteworthy that approximately 15% of lung cancer patients harbor pathogenic germline variants, most frequently in BRCA2, followed by CHEK2, ATM, TP53, BRCA1, and germline EGFR mutations.48 Therapies directed at these driver genes represent the cornerstone of precision oncology for NSCLC, with significant advancements continuously being made in this domain (Table 6).
In addition to targeted therapies, the principal modalities for NSCLC treatment include ICIs and ADCs.59 In recent years, ICIs such as pembrolizumab and nivolumab have been shown in pivotal clinical trials to significantly reduce the risk of recurrence or death when used with chemotherapy in the perioperative setting (encompassing neoadjuvant and adjuvant therapy).60,61 For locally advanced NSCLC, the PACIFIC trial (NCT02125461) established durvalumab consolidation therapy following concurrent chemoradiotherapy as the standard of care, demonstrating significant improvements in both progression-free and OS.62 The durability of this benefit has been confirmed by long-term follow-up data.63 In the first-line treatment of advanced disease, beyond the standard immuno-chemotherapy combination, a “dual immunotherapy” regimen (anti-PD-1/PD-L1 plus anti-CTLA-4) with limited chemotherapy has also emerged as a viable strategy. The POSEIDON study (NCT03164616), for instance, showed that durvalumab plus tremelimumab combined with chemotherapy conferred a survival benefit in a subset of patients with advanced NSCLC.64
ADCs, which conjugate highly specific monoclonal antibodies to potent cytotoxic agents, have recently been established as a cornerstone of NSCLC therapy, complementing targeted and immune-based approaches. One mechanism by which ADCs enhance the therapeutic landscape is by targeting proteins like HER2. T-DXd, an ADC directed against HER2, demonstrated remarkable efficacy in the DESTINY-Lung02 trial (NCT04644237), achieving a durable objective response rate over 50% in pretreated patients with HER2-mutant advanced NSCLC.65 In contrast to therapies aimed at oncogenic driver mutations, ADCs can also be directed against overexpressed cell-surface antigens. TROP2, a protein broadly overexpressed in NSCLC, is a promising ADC target. In the TROPION-Lung01 trial (NCT04656652), datopotamab deruxtecan significantly improved progression-free survival versus docetaxel in previously treated patients, with particular benefit in the non-squamous histology subgroup, and is expected to become a practice-changing agent in later-line settings.66 Sacituzumab govitecan, another TROP2-ADC approved for other cancers, is also under active investigation in NSCLC (NCT05089734).67 Furthermore, MET-targeting ADCs like telisotuzumab vedotin (Teliso-V) have shown promising activity in patients with MET-overexpressing NSCLC (NCT03539536) and are being evaluated in combination with the EGFR tyrosine kinase inhibitor (TKI) erlotinib (NCT02099058), indicating their potential as a novel therapeutic strategy for this patient population.68,69
Despite these therapeutic pillars, significant challenges persist in the treatment of NSCLC. The clinical efficacy of existing therapies is frequently constrained by the immunosuppressive tumor microenvironment, tumor heterogeneity, and immune evasion mechanisms, which often lead to suboptimal outcomes. To address these limitations, therapeutic vaccines have emerged as a promising frontier in immuno-oncology. This strategy is designed to actively orchestrate and augment the anti-tumor immune response by inducing a robust population of high-avidity, tumor-specific T cells, particularly CD8+ cytotoxic T lymphocytes. The goal is twofold: to eliminate existing tumors and to establish durable immunological memory to prevent disease recurrence, thereby offering a compelling therapeutic avenue.70 Current NSCLC vaccine development encompasses several technological platforms, including nucleic acid-based, peptide-based, cell-based (primarily dendritic cell vaccines), and viral vector-based approaches. While recent comprehensive reviews by García-Pardo et al. (2022) and Wang et al. (2025) have provided detailed summaries of vaccine mechanisms and cataloged ongoing clinical trials, respectively.71,72 the present review complements these efforts. We employ a bibliometric approach to provide a macroscopic analysis of the field’s historical evolution, intellectual structure, and emerging trends, offering a distinct and quantitative perspective on the state of NSCLC vaccine research.

Tumor cell vaccines
The investigation into tumor cell vaccines originated in the late 19th century with William Coley’s use of inactivated bacterial extracts, known as Coley’s toxin, to induce tumor regression. Although this therapeutic strategy was not underpinned by contemporary immunological principles and its mechanism of action remained unclear, the concept of activating a systemic inflammatory response to combat tumors established a conceptual foundation for subsequent research.73 By the mid-20th century, research shifted toward autologous and allogeneic tumor cell lysates with the objective of eliciting an immune response via the tumor’s inherent antigens. However, clinical efficacy was circumscribed by the technological limitations of the era, including inefficient antigen presentation and inadequate immunogenicity. Clinical trials in the 1960s utilizing allogeneic lung cancer cell lysate vaccines achieved only transient tumor regression in a minority of patients and did not significantly extend median survival. While this period of inquiry did not yield substantial therapeutic advances, it provided invaluable clinical experience that informed future technological innovations.74
The advancement of genetic engineering technologies in the 1990s represented a critical juncture in the evolution of tumor cell vaccines, facilitating the development of genetically engineered vaccine platforms.75 Researchers significantly augmented vaccine immunogenicity by transfecting tumor cells with genes encoding cytokines, such as GM-CSF. A Phase I/II clinical trial conducted in 1999 on patients with advanced NSCLC demonstrated that an autologous tumor cell vaccine engineered to express Granulocyte-macrophage colony-stimulating factor was well-tolerated and induced complete responses, with durations of 6–22 months, in three participants. Moreover, a significant positive correlation was observed between the level of Granulocyte-macrophage colony-stimulating factor secretion by the vaccine and patient survival. These findings underscored the therapeutic potential of genetic engineering while simultaneously revealing the constraints of vaccine monotherapy.76
Subsequent to the 2010s, a more profound comprehension of the TME has propelled the development of tumor cell vaccines into a new era of clinical translation, characterized by personalized and combination therapies as principal investigative strategies. A key research focus during this period has been the synergistic application of vaccines with ICIs. A Phase II trial in 2017 involving patients with advanced NSCLC reported that the CIMAvax-EGF vaccine, when administered in combination with platinum-based chemotherapy, extended the median overall survival to 14.7 months in a subgroup with high baseline epidermal growth factor (EGF) concentrations, a significant improvement over the 8.6 months observed in the control group (P < .0001). Furthermore, a positive correlation was identified between patient-generated antibody titers and survival outcomes.77
From a technological standpoint, the delivery systems for tumor cell vaccines have evolved from conventional viral vectors to advanced biomaterials. Early vaccine formulations frequently employed viral vectors, such as adenovirus and vaccinia virus, for tumor cell transfection. Although these vectors afford high transfection efficiency, they are encumbered by challenges including preexisting host immunity and intricate manufacturing processes.78,79 In contrast, contemporary vaccine platforms increasingly leverage lipid nanoparticles for mRNA delivery or electroporation for the direct loading of neoantigen peptides onto DCs. These technological innovations have markedly enhanced the efficiency of antigen presentation. A single-arm, multicenter exploratory trial (NCT02956551) involving patients with advanced lung cancer demonstrated that the personalized neoantigen-pulsed dendritic cell vaccine prepared via electroporation achieved an objective response rate (ORR) of 25% and a disease control rate (DCR) of 75% in 12 patients with metastatic lung cancer who had failed multiple lines of treatment. The median progression-free survival (mPFS) reached 5.5 months, and the median overall survival (mOS) was 7.9 months. Notably, all treatment-related adverse events (TRAEs) were grade 1–2, with no dose-limiting toxicities (DLTs) observed.80 Compared to other nucleic acid-based vaccines, RNA vaccines possess the advantages of a rapid production timeline (several weeks) and the capacity to elicit robust immune responses at low dosages, albeit with the logistical requirement of a stringent cold chain.81 Tumor cell vaccines, conversely, can stimulate local immune responses through the in situ release of cytokines, though their personalized manufacturing is both complex and resource-intensive. The distinct attributes of these two technological approaches provide a compelling rationale for their combined application. Notably, the real-world efficacy of the tumor cell vaccine has been fully validated. In a Phase IV trial conducted across 119 community clinics, 741 patients with advanced NSCLC received treatment with the CIMAvax-EGF vaccine. Among these patients, those who completed the loading dose vaccination achieved a mOS of 9.9 months, while the mOS was further extended to 12 months in patients with baseline high EGF levels. Additionally, scores from the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire (QLQ-C30) demonstrated sustained improvements in patients’ functional status, confirming the vaccine’s feasibility and safety in primary care settings.80
The developmental trajectory of tumor cell vaccines for NSCLC has progressed from the empirical applications of Coley’s toxin to the technological advancements of genetic engineering, and now to the clinical investigation of personalized vaccines in combination with immunotherapy. This field has advanced through a continuous cycle of challenges and breakthroughs. With the ongoing optimization of antigen screening methodologies, innovation in delivery systems, and an expanding understanding of the TME, tumor cell vaccines are positioned to offer distinct therapeutic value. They are anticipated to become a crucial component in the comprehensive treatment paradigm for NSCLC, particularly as adjuvant therapy post-surgery and as salvage therapy following the emergence of treatment resistance, especially in patient cohorts characterized by a high tumor mutational burden or specific molecular profiles.82,83

Peptide vaccines
The clinical application of peptide-based vaccines in NSCLC commenced in the 1980s, subsequent to the identification of TAAs.84 During this initial phase, investigators identified aberrantly expressed proteins in lung cancer cells, such as MUC1 and HER2, and began to evaluate the utility of synthetic peptides for eliciting an immune response. Early clinical trials predominantly utilized single-antigen peptides. For instance, a short peptide vaccine targeting MUC1 elicited only a limited humoral response in small-scale studies and failed to demonstrate a significant improvement in median survival relative to conventional therapies.85 The principal technological constraints of this period were the low immunogenicity of tumor antigens and the absence of effective delivery systems, which precluded the sustained activation of a robust immune response. Multiple Phase I/II trials conducted throughout the 1990s consistently reported that ORR for peptide monotherapies were generally under 10%, with the majority of patients experiencing disease progression within six months.86
Advances in adjuvant technology during the 2000s marked a significant turning point for peptide vaccines, with the introduction of Montanide ISA-51 representing a key milestone.87,88 This water-in-oil emulsion adjuvant enhances the recruitment of antigen-presenting cells and, when formulated with peptide vaccines, effectively promotes a Th1-polarized immune response. A 2003 study in patients with HER2-positive NSCLC showed that a HER2 peptide combined with Montanide yielded a three- to five-fold increase in the frequency of IFN-γ-secreting T cells in peripheral blood, with some patients achieving disease stabilization for over 12 months.89 In parallel, Stimuvax (BLP25), a vaccine comprising a liposome-encapsulated MUC1 peptide adjuvanted with Montanide, was developed. In a Phase II trial, Stimuvax extended the median survival for patients with Stage III NSCLC to 30.6 months, a substantial improvement over the 13.3 months recorded in the control arm.27,90 Despite these promising results, the pivotal Phase III START trial, reported in 2013, failed to demonstrate a significant improvement in OS. This outcome underscored the inherent limitations of single-antigen vaccines in addressing the challenge of tumor heterogeneity.
With advancements in immunological science, development strategies shifted toward multi-epitope designs and combined adjuvant systems. Researchers began to engineer multi-epitope vaccines by linking distinct antigen peptides, such as a fusion of P467 peptides derived from HER2, and incorporating Toll-like receptor agonists to amplify the immune response91 A notable example from this period is the CIMAvax-EGF vaccine, developed in Cuba, which targets the EGF receptor to inhibit tumor growth signaling pathways, thereby demonstrating clinical efficacy.92
In the late 2010s, the field of peptide vaccines advanced into an era defined by precision medicine and combination therapy. Research investigating the MAGE-A3 vaccine identified a predictive signature of 84 immune-related genes capable of stratifying a patient subpopulation with a high likelihood of clinical benefit; within this group, adjuvant vaccination following surgery resulted in a near doubling of disease-free survival.93 Concurrently, significant progress was made in personalized peptide vaccines. A multi-epitope vaccine, tailored to a patient’s unique tumor mutational profile, achieved a 75% disease control rate in a small-cohort study. Notably, all four patients in this study with PD-1 resistant disease achieved stable disease following treatment with the combination therapy.94
Currently, peptide vaccines continue to confront several challenges. The immunosuppressive TME can obstruct the infiltration of vaccine-induced effector cells into tumor lesions, while the long-term administration of adjuvants like Montanide carries a risk of local inflammatory reactions. Future research may prioritize the development of novel adjuvant systems. Modern delivery systems represented by lipid nanoparticles (LNPs) have surpassed traditional adjuvants, demonstrating tremendous potential in eliciting durable and robust anti-tumor immune responses. They enable efficient and safe delivery of multiple antigens, while facilitating antigen enrichment and presentation in lymph nodes. A Phase I clinical trial of personalized mRNA neoantigen vaccines delivered via LNPs in melanoma patients showed that the vaccines induced high-intensity polyclonal neoantigen-specific T cell responses and exerted synergistic effects with PD-1 inhibitors, exhibiting potential to prevent recurrence in high-risk patients. This provides strong human data support for the application of similar technologies in NSCLC.35 An alternative strategy involves the formulation of triplet regimens that combine vaccines with immunomodulators and chemotherapy, leveraging the immunogenic cell death induced by chemo-radiotherapy to augment vaccine efficacy. A Phase I/II study (NCT03141463) evaluated the combination of a carcinoembryonic antigen (CEA)-targeting peptide vaccine, nivolumab, and pemetrexed plus carboplatin as first-line treatment for patients with advanced NSCLC positive for CEA expression. Results showed that the triplet regimen was well-tolerated and elicited robust CEA-specific T cell immune responses. Among efficacy-evaluable patients, the ORR reached 75%, with a mPFS of 9.7 months. These efficacy data were superior to those of immune checkpoint inhibitor plus chemotherapy in historical controls during the same period. Furthermore, the vaccine-induced specific T cell responses were associated with better clinical outcomes.95 Furthermore, the application of single-cell sequencing could refine antigen selection and improve the precision of neoantigen prediction. Currently, researchers have developed a rapid T cell receptor (TCR) assembly method that enables cloning construction within 2 days. By integrating single-cell sequencing data, this method simultaneously screens for tumor-specific TCRs, epitopes, and HLA subtypes, significantly enhancing the efficiency and precision of antigen selection. This underscores the great potential of single-cell sequencing technology in optimizing antigen selection for cancer immunotherapy.96 Although the clinical development of peptide-specific vaccines for NSCLC has encountered variability, the field has evolved from early single-peptide formulations to contemporary personalized multi-epitope vaccines. With the maturation of combination strategies and the application of predictive biomarkers, these vaccines are progressively establishing their role as a significant adjunctive modality in the immunotherapy of lung cancer.97

DNA and RNA vaccines
During the late 1990s, advances in molecular biology catalyzed the investigation of nucleic acid vaccines for cancer therapy. The first proof-of-concept study for an mRNA-based cancer vaccine was reported in 1996, which involved the ex vivo pulsing of DCs.98 Research during this period was predominantly focused on technological validation, with efforts centered on administering DNA plasmids encoding TAAs to elicit anti-tumor immune responses. In the context of NSCLC, this early research prioritized the identification and validation of suitable lung cancer-associated antigens, including cancer-testis antigens such as the MAGE family proteins, NY-ESO-1, and survivin.99 However, these first-generation DNA vaccines relied on basic plasmid vectors delivered via conventional intramuscular injection, a method characterized by low transfection efficiency and insufficient immune activation, which collectively contributed to suboptimal preclinical outcomes.100
A significant breakthrough in DNA vaccine technology occurred in the 2000s with the implementation of electroporation. A study conducted by Best et al. demonstrated that electroporation-assisted DNA vaccine delivery generated a more robust CD8+ T cell immune response compared to either conventional intramuscular injection or gene gun administration.101 This technique applies controlled electrical pulses to transiently increase cell membrane permeability, thereby enhancing the cellular uptake of plasmid DNA.
Concurrently, the field of mRNA vaccines underwent major technological maturation. The development of lipid nanoparticle delivery systems effectively addressed the critical challenges of RNA instability and inefficient in vivo delivery. Furthermore, the strategic use of modified nucleosides, such as pseudouridine, was shown to mitigate excessive innate immune activation while improving protein expression efficiency.100 These innovations paved the way for clinical translation in NSCLC. For instance, the RNActive platform developed by CureVac yielded CV9201, an mRNA vaccine encoding five NSCLC-associated TAAs. In a Phase I/II trial, 46 patients with advanced NSCLC received a series of intradermal injections, resulting in 63% of evaluable patients mounting a T cell response against at least one of the encoded antigens.102 Subsequently, the CV9202 vaccine, which augmented the CV9201 backbone with the MUC1 antigen, was evaluated in combination with local radiotherapy in patients with Stage IV NSCLC, demonstrating a favorable safety and immunogenicity profile (NCT01915524).21 During this time, major breakthroughs were also achieved in mRNA vaccine formulation. The development of the LNP delivery system addressed the critical challenges of RNA instability and inefficient delivery. Furthermore, the use of modified nucleosides, such as pseudouridine, reduced excessive innate immune activation and enhanced protein expression efficiency.103
The advent of next-generation sequencing fundamentally altered the paradigm for cancer vaccine development, leading to the emergence of the neoantigen concept. Neoantigens are novel, patient-specific epitopes generated by somatic mutations within a tumor. Because they are absent from the host’s normal proteome, they possess high tumor specificity and potent immunogenicity and are not subject to central immune tolerance.104,105
Among the first personalized neoantigen vaccines to enter clinical evaluation for NSCLC was NEO-PV-01, a long-peptide formulation designed to target up to 20 neoantigens unique to each patient’s tumor. In a Phase Ib trial combining NEO-PV-01 with pembrolizumab in patients with advanced NSCLC, melanoma, or bladder cancer, the vaccine induced both neoantigen-specific CD4+ and CD8+ T cell responses and demonstrated evidence of epitope spreading.106 Concurrently, progress was made in non-personalized DNA vaccine technology. For instance, a DNA vaccine encoding Human Papillomavirus E6/E7 antigens fused to calreticulin, delivered via electroporation, showed significant anti-tumor activity.104 Although this work was conducted in the context of cervical cancer, it provided a valuable technological framework for the application of DNA vaccines to other solid malignancies.
The establishment of ICIs as a standard of care for NSCLC created a compelling therapeutic rationale for combining them with nucleic acid vaccines. The efficacy of PD-1/PD-L1 inhibitors is contingent upon a preexisting pool of tumor-specific T cells, which are often sparse or absent; nucleic acid vaccines can directly address this limitation by inducing or expanding such a population, thereby creating synergy.107 This hypothesis was tested in a 2018 Phase Ib trial where NEO-PV-01 was administered with pemetrexed, carboplatin, and pembrolizumab as a first-line regimen for advanced non-squamous NSCLC. The combination demonstrated a manageable safety profile, and post-vaccination, neoantigen-specific T cell responses were detected, including those targeting KRAS G12C and G12V mutations.93 Similarly, RO7198457, a personalized neoantigen vaccine based on an RNA-lipoplex platform capable of encoding up to 20 neoantigens, was shown to induce neoantigen-reactive T cells in a Phase Ia trial across various advanced solid tumors, including lung cancer (NCT03289962).108
The clinical success of mRNA vaccines during the COVID-19 pandemic provided significant impetus for their application in oncology. One such candidate, BNT116, is an intravenously administered, unmodified RNA-lipoplex vaccine encoding six TAAs commonly expressed in NSCLC. In the LuCa-MERIT-1 Phase I trial (NCT05142189), BNT116 was assessed in combination with cemiplimab in patients with advanced NSCLC who were ineligible for first-line chemotherapy. As of December 2024, data from 20 patients indicated a manageable safety profile, with all treatment-related adverse events being mild.109 A subsequent Phase II randomized controlled trial (NCT05557591) is currently comparing the efficacy of BNT116 plus cemiplimab against cemiplimab monotherapy in patients with PD-L1-high advanced NSCLC.110
Next-generation platforms under investigation include self-amplifying RNA, which can replicate intracellularly to prolong antigen expression and permit dose reduction, and circular RNA, which offers exceptional stability and potential for sustained protein production. In parallel, the DNA vaccine domain continues to progress; a Phase I trial of a personalized neoantigen DNA vaccine delivered via electroporation in patients with triple-negative breast cancer confirmed its safety and immunogenicity, as evidenced by the induction of neoantigen-specific T cell responses.111 Although this study was not in lung cancer, its findings provide a relevant precedent for the application of this technology in NSCLC.
Future research is focused on several key areas, including the development of novel delivery systems to enhance tumor targeting and reduce systemic toxicity, alongside the continued optimization of combination regimens. An open-label Phase I/II clinical trial (NCT03164772) evaluated the efficacy of the mRNA vaccine BI 1,361,849 in combination with immune checkpoint inhibitors for the treatment of metastatic NSCLC. In Arm A (mRNA vaccine + durvalumab), the PFS rates at Week 8 and Week 24 were 47.8% and 43.5%, respectively, whereas the corresponding rates in Arm B (mRNA vaccine + durvalumab + tremelimumab) were 32.4% and 8.8%. These findings indicate that the combination of the mRNA vaccine with a single PD-L1 antibody exhibits superior efficacy.112 The groundbreaking advances achieved in the field of melanoma have provided important references for NSCLC. The phase II randomized controlled trial KEYNOTE-942 demonstrated that treatment with the personalized neoantigen mRNA vaccine mRNA-4157 in combination with pembrolizumab reduced the risk of recurrence or death by 49% and the risk of distant metastasis or death by 62% in patients with completely resected high-risk melanoma, compared with pembrolizumab monotherapy. The recurrence-free survival rate increased from 62% to 79% after a median follow-up of 3 years (American Society of Clinical Oncology; PubMed).113,114 This success has validated the synergistic effect of mRNA vaccines combined with immune checkpoint inhibitors, thereby providing strong evidential support for the application of this strategy in NSCLC.115,116 with personalized mRNA vaccines showing notable potential in patients with a high tumor mutational burden. A study by McGranahan et al. demonstrated that the combination of high tumor mutational burden (TMB) and low intratumoral neoantigen heterogeneity (ITH < 1%) has a superior ability to predict the efficacy of immune checkpoint inhibitors compared with the use of TMB alone.117 The identification and validation of predictive biomarkers, such as ctDNA dynamics, baseline tumor immune infiltration, and PD-L1 expression, are critical for refining patient selection.110,118 A study demonstrated that in patients with advanced NSCLC, blood tumor mutational burden (bTMB) ≥ 6 correlated with prolonged reached 5.5 months among those receiving anti-PD-1/PD-L1 therapy, suggesting that bTMB may serve as a promising biomarker for predicting clinical benefit.119
Spanning nearly three decades, the development of DNA and RNA vaccines for NSCLC has progressed from foundational proof-of-concept studies to multifaceted clinical translation. The continued maturation of vaccine platforms, optimization of delivery systems, embrace of personalized medicine, and rational integration with established therapies position nucleic acid vaccines as an increasingly vital component in the comprehensive treatment of NSCLC. With forthcoming results from pivotal Phase III trials and further technological refinement, this therapeutic modality holds new promise for improving outcomes for patients with NSCLC.
Although DNA/RNA vaccines have shown tremendous potential in the treatment of NSCLC, their clinical application still faces numerous challenges and limitations. First, there is a significant gap between immune responses and clinical efficacy. Take CV9201 as an example: while this mRNA vaccine can induce T-cell responses against at least one tumor antigen in 63% of evaluable patients, no improvement in PFS or overall survival (OS) has been observed.120 Secondly, tumor heterogeneity constitutes a major obstacle to the efficacy of vaccines. The high heterogeneity of tumor cells makes it difficult for a single vaccine to effectively target all tumor cell variants, and immunosuppressive factors in the tumor microenvironment may also weaken the immune response induced by the vaccine. In addition, the accuracy of antigen selection and prediction remains a significant technical challenge. Accurate identification of neoantigens present in a patient’s tumor requires advanced sequencing and bioinformatics analysis, and this process must be both efficient and accurate to ensure that the vaccine targets the most relevant antigens.113 Therefore, despite continuous advances in nucleic acid vaccine technology, to truly translate it into an effective therapeutic modality for NSCLC, breakthrough progress is still required in multiple aspects, including antigen discovery, vaccine design, optimization of delivery systems, development of combination therapy strategies, identification of biomarkers, and standardization of manufacturing processes.

Viral vector vaccines
The conceptual basis for viral-based cancer therapy emerged in the late 19th century from clinical observations of tumor regression following natural viral infections. Since the first such report in 1893, the field has progressed from serendipitous discovery to systematic investigation, evolving from the use of wild-type viruses to genetically engineered vectors and from monotherapies to combination strategies.114 A widely noted case from 1904, for example, described the regression of a cervical cancer patient’s tumor following an infection with the canine distemper virus, which drew significant attention from the medical community.121 However, constrained by the technological limitations of the era, these early investigations remained largely phenomenological.
The development of modern viral vectors began in the mid-20th century, with vaccinia virus and adenovirus emerging as foundational platforms. Vaccinia virus, with its historical precedent as the live agent in Jenner’s smallpox vaccine, had an established safety profile in humans.122 The successful in vitro cultivation of the virus in 1958 was a critical technical milestone that enabled its manipulation as a vector.123 Its biological properties – including a large 192 kb genome capable of accommodating multiple foreign genes and a strictly cytoplasmic life cycle that prevents integration into the host genome – make it a highly suitable vector candidate.124 Concurrently, pioneering research on adenoviruses was being conducted. Following their initial isolation from human adenoid tissue by Rowe et al.125 a key discovery was made in 1962 when Trentin et al. demonstrated that certain adenoviral serotypes were oncogenic in animal models, providing an early, albeit counterintuitive, rationale for their investigation in cancer therapy.126 A subsequent breakthrough occurred in the 1970s with the establishment of the 293 cell line by Graham and van der Eb, which facilitated the scalable production of replication-deficient adenoviral vectors and was instrumental for their eventual clinical use.127
The advent of recombinant DNA technology marked a transformative period for viral vector development. In 1982, the first recombinant vaccinia virus was constructed via the insertion of an exogenous gene, signaling the definitive shift from employing wild-type viruses to using precisely engineered vectors.128 During this era, alongside the development of the first replication-deficient adenoviral vectors that would become a standard for gene therapy.129 research into other viral families also expanded. Notably, interest in rhabdoviruses grew significantly after Stojdl et al. discovered in 1995 that these viruses could selectively replicate in tumor cells harboring defective interferon signaling pathways, establishing a clear mechanistic basis for their use as oncolytic vectors.130 These technological advances align with our bibliometric findings, which revealed a marked increase in publications during the exploratory phase from the 1990s to 2000s (Figure 2), reflecting the field’s transition from basic research to systematic preclinical investigations.
The early 21st century marked the transition of viral vector vaccines from preclinical development to clinical evaluation. In 2000, the oncolytic adenovirus ONYX-015 entered a Phase I clinical trial, representing one of the first formal clinical investigations of this therapeutic class.131 This was followed in 2003 by the first Phase I trial of TG4010, a vaccine based on a Modified Vaccinia Ankara vector expressing MUC1 and Interleukin-2 (IL-2). The study confirmed a favorable safety profile, and notably, a durable (14-month) regression of a metastatic lesion in a patient with lung cancer provided a strong initial rationale for its further development in NSCLC.132 Technological advancements continued, with the creation of second-generation adenoviral vectors in 2005, which featured enhanced safety and transgene capacity.133 A major regulatory milestone was achieved in 2006 with China’s approval of H101 (Oncorine), the world’s first licensed oncolytic virus drug.134 To address the challenge of preexisting immunity to common human adenovirus serotypes, researchers began to systematically develop chimpanzee adenovirus vectors, which were shown to induce effective immune responses even in the presence of anti-human adenovirus antibodies.135,136 By 2009, vectors such as ChAd3 were demonstrated to elicit immune responses comparable to their human counterparts while circumventing preexisting immunity, opening new avenues for their application.137
The approval of the first immune checkpoint inhibitor (ICI), ipilimumab, in 2011 inaugurated a new era in cancer immunotherapy and created a compelling rationale for combining viral vector vaccines with checkpoint blockade.138 The subsequent success of pembrolizumab in NSCLC in 2015 further accelerated the development of such combination strategies. Research began to focus on the hypothesis that viral vectors could convert immunologically “cold” tumors, which are poorly infiltrated by T cells, into “hot” tumors that are responsive to ICIs.139 In this context, clinical evaluation of TG4010 in advanced NSCLC progressed, with a Phase II trial in combination with chemotherapy showing encouraging efficacy signals.140 Subsequently, the Phase IIb TIME trial reported that the addition of TG4010 significantly improved 6-month progression-free survival, providing robust evidence for its therapeutic potential.141
More recently, the field has moved toward personalization and advanced multi-platform strategies. In 2020, Zhang et al. proposed the Virus-Infected Reprogrammed Somatic-cell-derived Tumor cell vaccine, a strategy that integrates viral vectors with personalized antigen design, signaling a shift toward bespoke viral-based therapies.142 This concept was further supported by work from Roy et al., which demonstrated that oncolytic viruses could serve as a potent adjuvant platform for personalized cancer vaccines.143 Furthermore, sophisticated prime-boost regimens are being explored; a clinical study using a ChAd68 vector prime followed by a self-amplifying mRNA boost demonstrated good safety and immunogenicity in patients with advanced metastatic solid tumors, including NSCLC, highlighting the potential of combining distinct technological platforms.144 Institutional collaboration network analysis (Figures 7 and 8) revealed intensified partnerships between academic centers and pharmaceutical entities (e.g., FDA, Novartis) from 2015 to 2025, reflecting the field’s maturation into an integrative translational research ecosystem.
A real-world study published in 2025 assessed the efficacy of oncolytic Coxsackievirus CVA21 combined with pembrolizumab in advanced NSCLC.145 Analysis of paired pre- and post-treatment biopsies demonstrated that CVA21 substantially modulated tumor cell immunogenicity and reshaped the tumor microenvironment, with tumor volume reductions reaching 80% particularly in patients previously failing ICIs therapy. This clinical observation aligns with mechanistic insights from basic research: oncolytic viruses disrupt tumor-mediated immunosuppression, promote intratumoral T-cell infiltration, and thereby enhance ICIs responsiveness.146
However, clinical translation of viral vector vaccines faces substantial challenges. Antiviral immune responses during systemic administration, tumor stromal barriers impeding viral penetration, and negative immunoregulation within the tumor microenvironment collectively limit viral dissemination and therapeutic efficacy.147 Bibliometric data indicate that personalized viral vector vaccines and multi-platform combination strategies are emerging as research frontiers. Such cross-platform integration represents a key innovation trajectory in cancer vaccine development. Recent work has introduced the concept of virus-infected reprogramming of somatic cell-derived tumor cell vaccines (VIReST), integrating viral vectors with personalized antigen design and signaling a shift toward customized viral therapeutics.142
Although most current clinical trials remain in phase I/II exploration, with only limited progression to phase III,141 the potential of viral vector vaccines as an immunotherapeutic platform is gaining recognition. Future research must prioritize optimizing viral design, refining delivery systems, and identifying optimal combination regimens to maximize clinical benefits of this therapeutic modality.

DC vaccines
As the most potent professional antigen-presenting cells in the body, Dendritic Cells (DCs) play a pivotal role in initiating and regulating specific immune responses, and DC-based immunotherapeutic strategies represent a promising therapeutic avenue for patients with NSCLC. The discovery and naming of DCs in the mouse spleen by Steinman and Cohn in 1973 laid the foundation for subsequent immunotherapy research.148 Later work by Steinman and colleagues confirmed that DCs are the critical initiators of naive T cell responses, thereby establishing their central position in adaptive immunity.149 However, substantial progress in DC-based cellular research was not achieved until 1992, when Inaba et al. developed a method for expanding large quantities of DCs from bone marrow precursors, and Young and Steinman demonstrated that DCs could effectively activate tumor-specific Cytotoxic T Lymphocytes.150,151
In the late 1990s, the concept of the DC vaccine was formally established when Mayordomo et al. first reported that DCs loaded with tumor antigen peptides could induce an anti-tumor immune response in a murine model.152 The first Phase I clinical trial of a DC vaccine was conducted by Hsu et al. in 1996 in patients with B-cell lymphoma; although not focused on lung cancer, this study confirmed the safety and preliminary efficacy of the approach.153 Subsequently, a study applying DC vaccines for the treatment of advanced melanoma, which reported objective responses in 5 of 16 patients, further stimulated the application of this strategy to solid tumors.154
In the early 21st century, the application of autologous DC vaccines was extended to the treatment of NSCLC. Following an initial report in 2000, Hirschowitz et al. published a Phase I/II clinical trial in 2003 with an expanded cohort of 16 patients with advanced NSCLC. The results demonstrated that the treatment was safe and capable of eliciting an immune response in some patients.155,156
In 2006, Perroud et al. developed a novel method for loading DCs with apoptotic tumor cells, a strategy that provides a more comprehensive spectrum of tumor antigens. The initial application of this approach in patients with NSCLC demonstrated favorable immunogenicity.157 Building on the principle of a broad antigen profile, Um et al. employed a DC vaccine activated with alpha-galactosylceramide (α-GalCer) to concurrently stimulate both NKT cells and conventional T cells in patients with advanced NSCLC. In contrast, a subsequent Phase II clinical trial conducted by Antonia et al., which utilized a DC vaccine loaded with a specific MAGE-A3 peptide in MAGE-A3-positive NSCLC patients, failed to meet its primary endpoints.158
Beginning in 2012, DC vaccines were increasingly evaluated in combination therapy regimens. Sebastian et al. completed a multicenter Phase II clinical trial using a DC vaccine loaded with multiple TAAs (CVac) as maintenance therapy for NSCLC, with results indicating that the treatment could prolong progression-free survival.21 Concurrently, Hu et al. assessed the efficacy and safety of co-culturing DCs with autologous tumor lysate and pemetrexed as a second-line treatment for 27 patients with advanced lung adenocarcinoma. Although the study lacked a pemetrexed monotherapy control arm, its findings suggested that this combination therapy demonstrated promising clinical activity.159 Nevertheless, until 2020, the development of DC vaccines was largely confined to Phase I/II clinical trials that yielded only preliminary results. Our citation burst analysis substantiates this shift toward combination strategies, with terms including “immune checkpoint inhibitors” and “combination therapy” showing rising citation frequency since 2015 (Figure 15).
More recently, research has focused on integrating DC vaccines with other advanced technologies to enhance their efficacy. For instance, the application of nanotechnology has been shown to improve their antigen-presenting efficiency and augment T cell activation.160 Furthermore, CRISPR gene-editing technology is being explored to potentiate DC vaccine function; studies have shown that knocking out immunosuppressive molecules such as Programmed death-ligand 1 (PD-L1) significantly improves the anti-tumor effects of DC vaccines.161
Real-world clinical evidence post-2020 has validated the synergistic potential of DC vaccines with ICIs, a trend prominently reflected in our journal co-citation network. Several studies demonstrated favorable disease control with personalized neoantigen DC vaccines combined with ICIs in previously treated patients.162,163 These clinical outcomes corroborate the increased co-occurrence of “DC vaccine” and “pembrolizumab/nivolumab” keywords identified in our analysis (Figure 13(B)), illustrating the field’s evolution toward integrative immunotherapy approaches.
Recently, a multicenter Japanese trial by Takahashi et al. administered intradermal WT1 peptide-pulsed DC vaccines to 260 advanced NSCLC patients, reporting median survival of 20.4 months in patients with significant vaccine responses versus 8.8 months in weak responders (P < .001),164 which not only confirmed the clinical feasibility of DC-ICI combination therapy but also aligned with the sustained citation burst of “immune checkpoint inhibitors” observed from 2018 to 2025 in our temporal keyword analysis (Figure 15(D)), underscoring the maturation of this therapeutic strategy.
The developmental trajectory of DC vaccines in NSCLC documented through our bibliometric analysis – spanning basic research (1970s–1990s), clinical translation (2000s), combination strategies (post-2012), and personalized neoantigen-nanotechnology integration (2020–2025) – has been substantiated by real-world clinical evidence. With advancing antigen screening methodologies, evolving delivery platforms incorporating nanotechnology and gene editing, and deepening tumor microenvironment understanding, DC vaccines are positioned to deliver distinctive therapeutic value.

Conclusion
This systematic bibliometric analysis offers the first quantitative mapping of the intellectual landscape of the NSCLC vaccine field, tracing its evolution from foundational studies to the current era of precision immunotherapy. The findings mirror the trajectory of clinical development, revealing a definitive paradigm shift from vaccine monotherapy toward synergistic combinations with established therapeutic modalities, including targeted therapy, ICIs, and ADCs.
With the advent of biomarker-driven precision medicine, ICIs have become a cornerstone of NSCLC treatment, prompting a strategic repositioning of therapeutic vaccines. Consequently, the research focus has shifted from validating the standalone efficacy of vaccines to exploring their potential as immunosensitizing agents capable of potentiating standard-of-care treatments. This trend is substantiated by our keyword analysis, where the persistent co-occurrence of terms such as “immune checkpoint inhibitors” and “RNA vaccine” reflects the integration of next-generation immunotherapies. Citation burst analysis reveals critical inflection points: the foundational GM-CSF vaccine era (1993–2010), platform diversification period (2005–2015), and the checkpoint inhibitor revolution (2012-present), with current hotspots focusing on mRNA optimization, AI-enhanced neoantigen prediction, and rational triplet regimen design.
This bibliometric evidence corresponds with emerging clinical trial designs, particularly those evaluating personalized neoantigen mRNA vaccines in combination with ICIs. Such strategies aim to leverage vaccines to induce and expand tumor-specific T-cell populations, thereby surmounting ICI resistance and augmenting the anti-tumor immune response. Real-world clinical data, including personalized DC vaccines achieving disease control rates of 75% in previously treated patients and mRNA vaccines demonstrating 49% reduction in recurrence risk when combined with pembrolizumab in melanoma (with ongoing NSCLC trials), validate the synergistic potential of these approaches.
Despite its systematic approach, this study has several boundaries that should be noted. Primarily, while Web of Science and Scopus provided a robust foundation for high-quality metadata, the exclusion of regional databases like CNKI or clinical-specific platforms like PubMed may limit the representation of non-English or specialized clinical research. Although data cleaning involved rigorous manual verification and professional tools like TeslaSCI, inherent challenges in entity disambiguation – such as author name variants – remain an industry-wide constraint in large-scale bibliometric analysis. Furthermore, while we achieved a high citation conversion rate of 98.4%, the analysis of internal citations naturally focuses on the corpus’s internal structure rather than its absolute global impact. Additionally, the results from VOSviewer and CiteSpace reflect patterns based on current parameter settings and author-designated keywords, which, while highly informative, represent a snapshot of a rapidly evolving field. Finally, as this study prioritizes peer-reviewed articles and reviews to ensure data quality, it does not encompass patents or gray literature, leaving room for future research to explore technological translation through different lenses.
In conclusion, this study delineates the evolutionary trajectory of NSCLC vaccine research through quantitative data and contextualizes it within the broader transformation of NSCLC therapeutic paradigms. This knowledge map, which synthesizes bibliometric data with a clinical narrative, confirms that the future of NSCLC vaccines lies not in replacing existing therapies but in their precise integration within multi-modal treatment frameworks. The ultimate objective is to facilitate a transition from targeted cell killing to durable, immune-mediated cure.

Supplementary Material

Supplemental Material