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Background: A peptide vaccine was produced containing B and T cell epitopes from the V3 and C4 Envelope domains of 4 subtype B HIV-1 isolates (MN, RF, CanO, & Ev91). The peptide mixture was formulated as an emulsion in incomplete Freund's adjuvant (IFA). Methods: Low-risk, healthy adult subjects were enrolled in a randomized, placebo-controlled dose-escalation study, and selected using criteria specifying that 50% in each study group would be HLA-B7+. Immunizations were scheduled at 0, 1, and 6 months using a total peptide dose of 1 or 4 mg. Adaptive immune responses in16 vaccine recipients and two placebo recipients after the 2nd immunization were evaluated using neutralization assays of sera, as well as ELISpot and ICS assays of cryopreserved PBMCs to assess CD4 and CD8 T-cell responses. In addition, 51Cr release assays were performed on fresh PBMCs following 14-day stimulation with individual vaccine peptide antigens. Results: 24 subjects were enrolled; 18 completed 2 injections. The study was prematurely terminated because 4 vaccinees developed prolonged pain and sterile abscess formation at the injection site-2 after dose 1, and 2 after dose 2. Two other subjects experienced severe systemic reactions consisting of headache, chills, nausea, and myalgia. Both reactions occurred after the second 4 mg dose. The immunogenicity assessments showed that 6/8 vaccinees at each dose level had detectable MN-specific neutralizing (NT) activity, and 2/7 HLA-B7+ vaccinees had classical CD8 CTL activity detected. However, using both ELISpot and ICS, 8/16 vaccinees (5/7 HLA-B7+) and 0/2 controls had detectable vaccine-specific CD8 T-cell responses. Subjects with moderate or severe systemic or local reactions tended to have more frequent T cell responses and higher antibody responses than those with mild or no reactions. Conclusions: The severity of local responses related to the formulation of these four peptides in IFA is clinically unacceptable for continued development. Both HIV-specific antibody and T cell responses were induced and the magnitude of response correlated with the severity of local and systemic reactions. If potent adjuvants are necessary for subunit vaccines to induce broad and durable immune responses, careful, incremental clinical evaluation is warranted to minimize the risk of adverse events. [ABSTRACT FROM AUTHOR]

In conjunction with a randomized trial of T-cell depletion versus conventional graft-versus-host disease (GVHD) prophylaxis, we assessed GVHD grading by comparing the transplant center 100-day score, a clinically calculated algorithm, and a blinded expert panel review (PR). Weekly skin, gut, and liver clinical staging; clinically verified differential diagnosis; biopsy information; cyclosporine levels; and initiation of treatment were reviewed and graded according to the consensus GVHD grading method modified by a prospectively determined grading algorithm that specified liver and gut downstaging if a differential diagnosis in that organ was identified. Transplant center (TC) determination of maximum grade was compared with the algorithm-calculated grade and the final expert PR. Of 404 patients reviewed, the TC grade concurred with the calculated algorithm grade in 72% (the algorithm upgraded 18% and downgraded 10%), whereas the TC grade agreed with the PR in 77% (the PR upgraded 12% and downgraded 11%). The calculated algorithm grade was nearly fully (92%) concordant with the final PR grade (the PR upgraded 0.7% and downgraded 7%). Blinded, duplicate reviews for quality control (n = 108) agreed with the initial review in 89% of cases. Algorithm and/or PR review reduced the TC-reported incidence of grade II (28% to 23%) and increased grade III (11% to 20%), whereas grade 0 (41% to 42%), grade I (13% to 12%), and grade IV (7% to 6%) were invariant. Recalculation of the algorithm grading without differential diagnosis downstaging reduced agreement with the TC to a small extent. The original algorithm changed 51 (13%) of 404 from grade 0 to II into grade III or IV or vice versa; calculation without the downgrade modified 44 cases (11%). Maximum acute GVHD grade had a major effect on 2-year disease-free survival, but assignment by TC, calculated algorithm, or final PR grade had little effect on survival within grades or grade categories 0 through II versus III or IV. We conclude that detailed and expert PR yields GVHD scoring that is internally consistent and reproducible with 89% concordance. Weekly recording of GVHD stage along with a calculated grading algorithm acknowledging differential diagnoses results in a final and maximum grade nearly fully concordant with the expert blinded PR. Multicenter prospective GVHD scoring using all available weekly staging and differential diagnosis data can be reliably assessed with a clinically relevant algorithm. This approach can thereby reduce investigator bias, facilitate comparison between centers, and perhaps eliminate the need for an expert PR. This technique should be used in future prospective studies of GVHD prophylaxis. [Copyright &y& Elsevier]