Therapeutic vaccines for advanced non-small cell lung cancer

BACKGROUND

New strategies in immunotherapy with specific antigens that trigger an anti-tumour immune response in people with lung cancer open the possibility of developing therapeutic vaccines aimed at boosting the adaptive immune response against cancer cells.

OBJECTIVES

To evaluate the effectiveness and safety of different types of therapeutic vaccines for people with advanced non-small cell lung cancer.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, Wanfang Data, and China Journal Net (CNKI) up to 22 August 2023.

SELECTION CRITERIA

We included parallel-group, randomised controlled trials evaluating a therapeutic cancer vaccine, alone or in combination with other treatments, in adults (> 18 years) with advanced non-small cell lung cancer (NSCLC), whatever the line of treatment.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Our primary outcomes were overall survival, progression-free survival, and serious adverse events; secondary outcomes were three- and five-year survival rates and health-related quality of life.

MAIN RESULTS

We included 10 studies with 2177 participants. The outcome analyses included only 2045 participants (1401 men and 644 women). The certainty of the evidence varied by vaccine and outcome, and ranged from moderate to very low. We report only the results for primary outcomes here. TG4010 The addition of the vector-based vaccine, TG4010, to chemotherapy, compared with chemotherapy alone in first-line treatment, may result in little to no difference in overall survival (hazard ratio (HR) 0.83, 95% confidence interval (CI) 0.65 to 1.05; 2 studies, 370 participants; low-certainty evidence). It may increase progression-free survival slightly (HR 0.74, 95% CI 0.55 to 0.99; 1 study, 222 participants; low-certainty evidence). It may result in little to no difference in the proportion of participants with at least one serious treatment-related adverse event, but the evidence is very uncertain (risk ratio (RR) 0.70, 95% CI 0.23 to 2.19; 2 studies, 362 participants; very low-certainty evidence). Epidermal growth factor vaccine Epidermal growth factor vaccine, compared to best supportive care as switch maintenance treatment after first-line chemotherapy, may result in little to no difference in overall survival (HR 0.82, 95% CI 0.66 to 1.02; 1 study, 378 participants; low-certainty evidence), and in the proportion of participants with at least one serious treatment-related adverse event (RR 1.32, 95% CI 0.88 to 1.98; 2 studies, 458 participants; low-certainty evidence). hTERT (vx-001) The hTERT (vx-001) vaccine compared to placebo as maintenance treatment after first-line chemotherapy may result in little to no difference in overall survival (HR 0.97, 95% CI 0.70 to 1.34; 1 study, 190 participants). Racotumomab Racotumomab compared to placebo as a switch maintenance treatment post-chemotherapy was assessed in one study with 176 participants. It may increase overall survival (HR 0.63, 95% CI 0.46 to 0.87). It may make little to no difference in progression-free survival (HR 0.73, 95% CI 0.53 to 1.00) and in the proportion of people with at least one serious treatment-related adverse event (RR 1.03, 95% CI 0.15 to 7.18). Racotumomab versus docetaxel as switch maintenance therapy post-chemotherapy was assessed in one study with 145 participants. The study did not report hazard rates on overall survival or progression-free survival time, but the difference in median survival times was very small - less than one month. Racotumomab may result in little to no difference in the proportion of people with at least one serious treatment-related adverse event compared with docetaxel (RR 0.89, 95% CI 0.44 to 1.83). Personalised peptide vaccine Personalised peptide vaccine plus docetaxel compared to docetaxel plus placebo post-chemotherapy treatment may result in little to no difference in overall survival (HR 0.80, 95% CI 0.42 to 1.52) and progression-free survival (HR 0.78, 95% CI 0.43 to 1.42). OSE2101 The OSE2101 vaccine compared with chemotherapy, after chemotherapy or immunotherapy, was assessed in one study with 219 participants. It may result in little to no difference in overall survival (HR 0.86, 95% CI 0.62 to 1.19). It may result in a small difference in the proportion of people with at least one serious treatment-related adverse event (RR 0.95, 95% CI 0.91 to 0.99). SRL172 The SRL172 vaccine of killed Mycobacterium vaccae, added to chemotherapy, compared to chemotherapy alone, may result in no difference in overall survival, and may increase the proportion of people with at least one serious treatment-related adverse event (RR 2.07, 95% CI 1.76 to 2.43; 351 participants).

AUTHORS' CONCLUSIONS

Adding a vaccine resulted in no differences in overall survival, except for racotumomab, which showed some improvement compared to placebo, but the difference in median survival time was very small (1.4 months) and the study only included 176 participants. Regarding progression-free survival, we observed no differences between the compared treatments, except for TG4010, which may increase progression-free survival slightly. There were no differences between the compared treatments in serious treatment-related adverse events, except for SRL172 (killed Mycobacterium vaccae) added to chemotherapy, which was associated with an increase in the proportion of participants with at least one serious treatment-related adverse event, and OSE2101, which may decrease slightly the proportion of people having at least one serious treatment-related adverse event. These conclusions should be interpreted cautiously, as the very low- to moderate-certainty evidence prevents drawing solid conclusions: many vaccines were evaluated in a single study with small numbers of participants and events.

Oncolytic Vaccinia Virus in Lung Cancer Vaccines

Therapeutic cancer vaccines represent a promising therapeutic modality via the induction of long-term immune response and reduction in adverse effects by specifically targeting tumor-associated antigens. Oncolytic virus, especially vaccinia virus (VV) is a promising cancer treatment option for effective cancer immunotherapy and thus can also be utilized in cancer vaccines. Non-small cell lung cancer (NSCLC) is likely to respond to immunotherapy, such as immune checkpoint inhibitors or cancer vaccines, since it has a high tumor mutational burden. In this review, we will summarize recent applications of VV in lung cancer treatment and discuss the potential and direction of VV-based therapeutic vaccines.

Immunotherapy for non-small cell lung cancer (NSCLC), as a stand-alone and in combination therapy

Non-small cell lung cancer (NSCLC) is of major concern for society as it is associated with high mortality and is one of the most commonly occurring of all cancers. Due to the number of mutational variants and general heterogeneity of this type of cancer, treatment using conventional modalities has been challenging. Therefore, it is important to have improved therapeutic treatments like immunotherapy, that can specifically treat the disease while causing minimal damage to healthy tissue and additionally provide systemic immunity. Cancer vaccines are an important element of cancer immunotherapy and have been approved for treatment of a limited number of cancers, including NSCLC. This article highlights scientific evidence for several therapeutic treatment strategies for NSCLC, alone or in combination, which offers new hope for those suffering. Although cancer vaccines have had some success as a monotherapy, their potential in a combination therapy needs to be critically analyzed for future applications.