A cancer vaccine currently being developed by pharmaceutical company GlaxoSmithKline has hit a wall of disappointment in a second test against lung cancer. The company, however, remains optimistic that it will find a sub-group of patients that would benefit from the treatment.

In a statement released Thursday, GlaxoSmithKline said that the experimental cancer vaccine MAGE-A3 did not help patients with non-small cell lung cancer in a late-stage Phase III trial of the treatment. MAGE-A3 is an experimental vaccine designed for people who already have established disease. It supposedly works by helping the patient's immune system so the disease would not return after surgery.

"GlaxoSmithKline plc (LSE:GSK) today announced that analysis of the MAGRIT trial, a phase III trial of its MAGE-A3 cancer immunotherapeutic in non-small cell lung cancer (NSCLC) patients, showed that the trial did not meet its first or second co-primary endpoint as it did not significantly extend disease-free survival when compared to placebo in either the overall MAGE-A3 positive population (first co-primary endpoint) or in those MAGE-A3-positive patients who did not receive chemotherapy (second co-primary endpoint)," the company said in a statement.

Vincent Brichard, senior vice president and head of immunotherapeutics at GSK Vaccines admitted that the company was disappointed by the results. Nonetheless, Brichard thanked all those involved in the randomized and placebo-controlled Magrit trial and said that the company remains committed to finding patients who may benefit from the experimental treatment.

"We want to thank all patients, their families and healthcare workers for their involvement in the MAGRIT trial. We are disappointed that the trial did not demonstrate a benefit for overall MAGE-A3 positive patient population, but we remain committed to the effort to identify a sub-population of NSCLC patients who may benefit from this investigational treatment," Brichard said.

The company has likewise said that "it will continue the trial until an analysis of the third co-primary endpoint is complete."

"GSK is continuing to evaluate in another phase III clinical study (DERMA) whether a gene signature can identify a sub population of melanoma patients that would benefit from the same investigational MAGE-A3 cancer immunotherapeutic," the company stated. "Work is progressing on the mathematical model to allow assessment of DFS in the gene signature population, the second co-primary endpoint in the study. The outcome is expected in 2015."