A randomized trial that studied the impact of the new vitespen vaccine, administered after surgery for kidney cancer , failed to demonstrate an increase in recurrence-free survival (RFS). More research is needed, according to the study authors, in order to know whether the vaccine can increase RFS if given to patients during the early stages of the disease. Results of the study – conducted by Dr Christopher Wood (M D Anderson Cancer Center, Houston, TX, USA) and colleagues – will be published in The Lancet and have been published early online.
Though it is common for patients with renal cell carcinoma (kidney cancer) to be treated with surgery , many face an increased risk of cancer recurrence since there is no supplemental treatment (or, adjuvant therapy) provided after surgery that has proved effective. In a randomized phase III trial, Wood and colleagues set out to analyze the efficacy of the vaccine vitespen used as an adjuvant therapy after surgery for kidney.
The trial was designed such that 818 patients, all about to undergo kidney surgery, were randomized to receive either vitespen or observation after the procedure – 409 patients in each group. The vitespen treatment consisted of an injection administered one time per week over a period of four weeks, followed by an injection every two weeks until the vaccine was exhausted. Since several patients failed to meet the necessary criteria to be included in the study after surgery, the final analysis consisted of 361 patients in the vitespen group and 367 in the observation group.
The main finding was the lack of a significant difference in RFS between the observation group and the vitespen group. Though a separate analysis showed that patients with early stage renal cell carcinoma (stage I or II disease) were about half as likely to experience cancer recurrence if they received the vaccine (15.2% in the vitespen group and 27.0% in the observation group), there was sufficient variance to render the difference not statistically significant.
“No difference in recurrence-free survival was seen between patients given vitespen and those who received no treatment after surgery for renal cell carcinoma. A possible improvement in recurrence-free survival in patients with early stage disease who received vitespen will require further validation,” conclude the Wood and colleagues.
A comment accompanying the article, written by Dr James Yang (National Cancer Institute, Bethesda, MD, USA), cautions that some researchers and companies can weaken the results of cancer immunotherapy studies because they dislike or disagree with the results of randomized clinical trials. In this case, Yang is referring to the manufacturers of vitespen who have pushed aside the overall negative results of the trial to focus on a potential positive outcome. “Such practices are akin to shooting the arrow first and being permitted to draw the target afterwards,” writes Yang.
Yang also takes issue with a press release issued by manufactures of vitespen that recommends the vaccine in Russia for patients with moderate risk kidney cancer. “Commercially driven efforts that spin or obfuscate the conclusions of such a trial should be vigorously resisted because such efforts severely erode its value,” he concludes.