Announced at the European Society for Medical Oncology (ESMO) Meeting 2014, GlaxoSmithKline’s investigational cancer immunotherapeutic, recMAGE-A3, does not increase survival of non-small cell lung cancer (NSCLC) patients when compared to a placebo in a phase 3 clinical trial. The findings regarding this now-terminated phase 3 clinical trial, MAGRIT, were also described in the abstract for the conference and presented by Professor Johann Vansteenkiste from University Hospitals Leuven.
In the study a total of 2,272 randomized and treated patients, received either 13 intramuscular injections of recMAGE-A3 to treat their cancer, or recMAGE-A3 along with AS15 cancer immunotherapy as an adjuvant treatment. The addition of adjuvant therapy did not enhance or inhibit recMAGE-A3 treatment, as neither group saw a benefit over patients treated with a placebo.
Measures of success were disease free survival, overall survival, lung cancer specific survival, disease-free specific survival, immunogenicity, safety, and health-related quality of life. An early interim analysis showed that a pre-specified boundary was not met, but the trial continued due to patient tolerance of the treatment. Among the side effects that occurred more often in the MAGE-A3 cancer immunotherapeutic group were pyrexia, injection site pain, fatigue, influenza-like illness, and myalgia. However, adverse events did not differ between the groups and occurred less than 1% of the time.
Disease free survival was 60.5 months and 57.9 months for the treatment and placebo groups, respectively, which was an insignificant difference. In the groups not receiving adjuvant therapy, disease free survival was 58.0 and 56.9 months, respectively.
Another aim of the trial was to study disease free survival in a potentially predictive gene signature. However, since there was no effect of treatment, a gene signature could not be established to predict patients who may benefit from treatment.
Although the results were not what were hoped, MAGRIT was the largest NSCLC clinical trial to this date and was the first to investigate immunotherapy with adjuvant therapy for early stage NSCLC. Dr. George Coukos, who discussed the study results, stated that low toxicity, ease of administration, and ability to induce anti-tumor memory are advantages to a vaccine for NSCLC. The “MAGE-A3 vaccine” demonstrates how a therapeutic against MAGE-A3, an antigen on some tumor cells, can be tolerated by patients, although there are some technicalities that have yet to be fixed.