Clinical StudiesDifferent Adjuvanticity of Incomplete Freund's Adjuvant Derived From Beef or Vegetable Components in Melanoma Patients Immunized With a Peptide VaccineRosenberg, Steven A.; Yang, James C.; Kammula, Udai S.; Hughes, Marybeth S.; Restifo, Nicholas P.; Schwarz, Susan L.; Morton, Kathleen E.; Laurencot, Carolyn M.; Sherry, Richard M.Author Information Surgery Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD Reprints: Steven A. Rosenberg, Surgery Branch, National Cancer Institute, National Institutes of Health, Building 10, CRC, Room 3-3940, 10 Center Drive, MSC 1201, Bethesda, MD 20892-1201 (e-mail: SAR@nih.gov). Received for publication October 23, 2009; accepted February 7, 2010 All investigator's have declared there are no financial conflicts of interest in regards to this work. Journal of Immunotherapy: July-August 2010 - Volume 33 - Issue 6 - p 626-629 doi: 10.1097/CJI.0b013e3181dac9de Buy Metrics Abstract Adjuvants are requisite components of many vaccines designed to elicit T-cell immunity although the exact components of commonly used adjuvants are not always fully defined. In 2006, owing to concerns of prion contamination, the formulation of Montanide ISA 51 Incomplete Freund's Adjuvant (IFA) was changed from using oleic acid isolated from beef tallow to that isolated from olives. In sequential clinical trials in the Surgery Branch, NCI patients at high risk for recurrence of melanoma were immunized with the gp100 melanoma/melanocyte antigenic peptide, gp100: 209-217 (210M), emulsified in the beef-derived IFA or the olive-derived IFA. The in vivo generation of gp100 reactive T cells was significantly less in patients receiving the olive compared with the beef IFA as assessed by both ELISPOT (P2=0.0001) and in vitro sensitization assays (P2=0.0001). Local skin reactions to the peptide emulsion were also far less severe using the olive IFA (P2=0.0003). Thus it seems likely that contaminants in the beef-derived IFA played an important role in the increased adjuvanticity of this preparation compared with the olive-derived IFA. These findings raise serious concerns related to the use of the available olive-derived IFA for immunization in clinical trials. A survey of ongoing clinical trials listed in ClinicalTrials.gov revealed 36 trials currently accruing patients that are using the olive-derived Montanide ISA 51 IFA. © 2010 Lippincott Williams & Wilkins, Inc.