Panmure Gordon has retained a 'hold' recommendation on shares of GlaxoSmithKline after the pharmaceuticals group reported "another disappointment" for its therapeutic cancer vaccine, MAGE-A3.Analysis of a phase III trial of its MAGE-A3 cancer immunotherapeutic in non-small cell lung cancer (NSCLC) patients showed that it did not meet its first or second co-primary endpoints. The company said it would continue the trial in order to assess the third co-primary endpoint in a smaller population.Panmure Analyst Savvas Neophytou said that given the disappointment in a previous phase III trial in melanoma last year, "we had written the product off so we make no changes to forecasts at this stage".He said that MAGE-A3 could have been one of three "particularly transformative pipeline opportunities" for GlaxoSmithKline. "MAGE-A3 is a therapeutic cancer vaccine, the holy grail of the industry, but was identified as very high risk because it is an unproven area. Therefore, we believe consensus forecasts for this product are heavily risk adjusted and do not expect today's news to trigger major downgrades. Rather we view today's events as a missed upgrading opportunity." Neophytou added: "With a further read-out pending we are not pinning much hope on the product."The stock trades at 14.1 times 2014 and 2015 earnings, a slight premium to the wider sector, he said.The shares were down 1.9% at 1,623.5p by 11:28.BC