Cyclophilin B peptide fails in phase 1 lung cancer trial.

2002 DEC 11 - (NewsRx.com & NewsRx.net) -- by Maria G. Essig, MS, ELS, senior medical writer - Phase 1 clinical trial results revealed that a cyclophilin B peptide vaccine was safe when given to lung cancer patients, but did not elicit a significant cytotoxic T lymphocyte (CTL) response.

Cyclophilin B (CypB) is a protein essential for T-cell activation. It contains two antigenic segments, CypB[subscript]84-92 and CypB[subscript]91-99, that stimulate a tumor-specific CTL response.

Rumi Gohara and colleagues at Kurume University School of Medicine in Japan conducted a phase 1 clinical trial involving 16 patients with advanced lung cancer who received subcutaneous inoculations of a vaccine containing the cyclophilin B CypB[subscript]91-99 peptide or a modified version of the peptide.

The CypB[subscript]84-92 peptide was used in only 2 patients because it provoked an immediate-type hypersensitivity reaction in the other 14 patients.

Although vaccination did not cause any serious adverse effects, neither did it elicit a significant cellular response to proteins or tumor cells in peripheral blood mononuclear cells (PBMC).

"These results suggest that the vaccination of CypB[subscript]91-99 peptide was safe, but failed to ...