Phase II study of cetrorelix, a luteinizing hormone-releasing hormone antagonist in patients with platinum-resistant ovarian cancer.

OBJECTIVE: The goal of this work was to study the anticancer activity of cetrorelix, a decapeptide with LHRH receptor antagonist properties in patients with platinum-resistant ovarian cancer. About 80% of primary ovarian cancers and cell lines bear LHRH receptors. Cetrorelix has anticancer activity in in vitro and in vivo ovarian cancer models. METHODS: Eligible patients with ovarian or mullerian carcinoma resistant to platinum chemotherapy received cetrorelix 10 mg subcutaneously every day. Eligibility criteria included age > or = 18, PS < or = 2, measurable disease, chemistries and blood counts in normal range, no estrogen replacement for at least 2 weeks, and no known allergic reactions to extrinsic peptide. In patients volunteering for a biopsy, tissue was taken to perform a LHRH receptor assay. RESULTS: Seventeen patients were treated. Median age was 58 years. Median performance status was 0. Median number of prior chemotherapies was 3. Three patients had partial remissions lasting 9, 16, and 17 weeks. Toxicities effects included grade 4 anaphylactoid reaction (one patient) controlled by cortisol and cimetidine, grade 2 histamine reaction (two patients), grade 2 arthralgia (one patient) 20% cholesterol increase (two patients, who did not require specific treatment), minor hot flushes, headache, and local skin reaction at the injection site. Six of seven samples were LHRH receptor positive for mRNA and/or ligand assay. Two responding patients were LHRH receptor positive. The patient who had no receptor did not respond. CONCLUSION: Cetrorelix has activity against ovarian cancer in this refractory population, and has minimal toxicity, except for potential anaphylactoid reactions. Activity may be mediated through the LHRH receptor.