Clinical trial of patients treated with DC vaccinesclinical study dataset
We obtained data from a trial in small cohorts of patients (3-9) who were vaccinated with differently composed DC-vaccines:
DC loaded with a single MAA-derived peptide (MAGE-3.A1 or -A2 or Na17.A2) or pulsed with 2 to 3 MAA-derived peptides (combinations of MAGE-3.A2, MAGE-C2.A2 or Na17.A2) or G4-DC loaded with 8 different peptides.
Our experiences can be summarized as follows:
(1) preparation of an autologous dendritic cell based vaccine was feasible for every patient enrolled in our studies;
(2) we did not observe vaccination related toxicities beside mild local skin reactions (CTCAEv3.0 grade 1/2) at the injection sites;
(3) objective tumor regression was observed in 4 patients (1 CR and 1 CR after resection of residual disease following regression of metastases) on a total of 10 patients that were able to receive the planned 6 biweekly vaccinations;
(4) all patients with regression of melanoma lesions following vaccination were found to have mounted a significant increase in the frequency of vaccine specific CTL in their peripheral blood and the appearance of a measurable CTL-frequency was seen between 8-13w after the first vaccine, furthermore, regression or stabilization of metastases has been coincident with the appearance of detectable or a significant rise (>10-fold) of CTL-frequencies;
(5) 2 patients with no residual disease following surgical metastasectomy who were vaccinated remain disease free at >18 months of follow-up, one of these patients qualifies for a CTL-response, the other for a borderline response;
(6) CTL-responses have been observed in 1 out of 3 patients treated with a mRNA-G4DC vaccine; this small number of patients does not allow for a comparison of efficacy between mRNA and MAA-peptide pulsed DC-vaccines.
An important conclusion that can be made from these pilot-observations is that the potential therapeutic effect of our DC-based MAA-vaccination approach does not occur instantly but is delayed by 8-12w following the first vaccination (i.e.12-16w after the isolation of PBMC by leukapheresis given the 4w that are necessary for preparation of the DC-vaccine and the extensive quality control). All patients in whom a benefit was seen in our study had a normal LDH and all but one patient, were chemo-naïve.
- organ type
- organism type
- Homo sapiens
- bodily part type
- experimental design type
- in vivo design experiment