Phase 2 Study of Trabectedin in Patients With Hormone Receptor-Positive, HER-2-Negative, Advanced Breast Carcinoma According to Expression of Xeroderma Pigmentosum G Gene.

BACKGROUND: Preclinical and clinical data suggest that xeroderma pigmentosum G gene (XPG) status might predict trabectedin efficacy. This phase 2 study evaluated the efficacy of trabectedin at a dose of 1.3 mg/m2 as a 3-hour intravenous infusion every 3 weeks in hormone receptor-positive, HER-2 (human epidermal growth factor receptor 2)-negative, advanced breast cancer patients according to the tumor level of XPG mRNA expression. PATIENTS AND METHODS: Patients were stratified into high-XPG (>3) or low-XPG (≤ 3) groups. The primary efficacy end point was progression-free survival (PFS) rate at 16 weeks (PFS4); secondary efficacy end points were overall response rate (ORR), duration of response, PFS, overall survival, and safety of trabectedin in this patient population. RESULTS: Forty-four patients were treated, 21 with high XPG and 23 with low XPG. Four high-XPG and 6 low-XPG patients experienced PFS4; the criterion for further recruitment (> 6 patients experienced PFS4) was thus not met, and recruitment was stopped. One high-XPG patient had a partial response (ORR, 5%). One low-XPG patient had a complete response, and 2 low-XPG patients had partial responses (ORR, 13%). Comparison of efficacy parameters between high-XPG and low-XPG patients showed no statistically significant differences. ORR in the efficacy population was 9.3%, median PFS was 1.9 months, and overall survival was 11.8 months. The safety of trabectedin in breast carcinoma was similar to that shown in other indications. CONCLUSION: Trabectedin as single agent had limited activity in hormone-positive, HER-2-negative advanced breast cancer. XPG mRNA expression was not predictive of trabectedin efficacy.

Phase I, dose-escalating study of elisidepsin (Irvalec(®)), a plasma membrane-disrupting marine antitumor agent, in combination with erlotinib in patients with advanced malignant solid tumors.

OBJECTIVE: To determine the recommended dose for phase II trials of elisidepsin (PM02734, Irvalec®) in combination with erlotinib in patients with advanced malignant solid tumors. METHODS: Open-label, dose-escalating, phase I study of intravenous elisidepsin administered weekly (days 1, 8 and 15) over 3 h as a flat dose (FD) and daily oral erlotinib, every 3 weeks. A pharmacokinetic analysis was done on blood samples collected around the first elisidepsin infusion. RESULTS: Thirty patients were treated across six different dose levels (DLs) ranging from elisidepsin 0.33-2.25 mg/erlotinib 100-150 mg. Two patients had dose-limiting toxicities: grade 3 bilirubin increase (DL3: 0.75 mg/150 mg) and a dose omission for > 2 weeks due to grade 3 alanine aminotransferase increase (DL6: 2.25 mg/100 mg). The daily erlotinib dose was escalated to 150 mg at DL2-DL5, but decreased to 100 mg at DL6, as most grade 3 toxicities were related to this agent only. The most frequent toxicities were transaminase increases (related to elisidepsin), and rash, pruritus and diarrhea (related to erlotinib). No objective responses were observed. Despite no overlapping toxicities, the combination was declared unfeasible due to frequent elisidepsin dose delays. The pharmacokinetics of elisidepsin/erlotinib was not significantly different from that of each agent alone. CONCLUSION: The difficulty in combining elisidepsin with the standard dose of erlotinib (150 mg), together with the lack of antitumor activity, made the combination unattractive for further development. The trial was closed without having determined a recommended dose.

Phase I study of elisidepsin (Irvalec®) in combination with carboplatin or gemcitabine in patients with advanced malignancies.

OBJECTIVE: To determine the maximum tolerated dose and the recommended dose (RD) for phase II trials of elisidepsin (Irvalec®) in combination with carboplatin or gemcitabine. METHODS: Open-label, dose-escalating, two-arm, uncontrolled, phase I study. Patients received carboplatin on Day (D) 1, followed by elisidepsin on D1 and D8, every 3 weeks, or gemcitabine on D1 and D15, followed by elisidepsin on D1 and D15, every 4 weeks. A pharmacokinetic analysis was done from blood samples collected during the first treatment infusion. RESULTS: Fifteen patients were treated with carboplatin/elisidepsin at doses from 4 AUC/1.0 mg flat dose (FD) to 5 AUC/2.5 mg FD. Two patients had dose-limiting toxicities (DLTs) at 5 AUC/2.0 mg, a dose delay >2 weeks due to grade-2 ALT increase and grade-3 thrombocytopenia, and a D8 infusion omission due to grade-3 ALT increase. The RD was established at 4 AUC/1.0 mg. Toxicity consisted mainly of mild-moderate anorexia, fatigue, and nausea. Twenty-two patients were treated with gemcitabine/elisidepsin at doses from 1,000 mg*m(2)/1.0 mg FD to 1,250 mg*m(2)/7.5 mg FD. Two patients had DLTs at 1,250 mg*m(2)/7.5 mg, both a D15 dose omission due to grade-2 ALT increase. The RD was defined at 1,250 mg*m(2)/5.0 mg. Toxicity consisted mainly of mild-moderate fatigue, pruritus, erythema, and myalgia. No objective response was observed. No relevant pharmacokinetic interaction was detected. CONCLUSION: Infra-optimal doses of elisidepsin and carboplatin and a lack of antitumor activity despite using active drug concentrations in combination with gemcitabine do not warrant further clinical development for these two combinations.

Phase II study of weekly PM00104 (ZALYPSIS(®)) in patients with pretreated advanced/metastatic endometrial or cervical cancer.

This open-label, two-arm, phase II clinical trial evaluated the antitumor activity and safety profile of PM00104 (Zalypsis(®)) administered as a 1-h, weekly, intravenous infusion (days 1, 8 and 15; every 4 weeks) at a dose of 2 mg/m(2) to patients with advanced and/or metastatic endometrial (EC) or cervical cancer (CC) after one previous line of systemic chemotherapy. Twelve patients (median age, 61.5 years) with pretreated EC received a median of 2 treatment cycles (range 1-5) and seven patients (median age, 38 years) with pretreated CC received 2 treatment cycles. None achieved objective tumor response. Median progression-free survival (PFS) was 1.8 months, and median overall survival (OS) was 5.5 months in EC (median follow-up = 20.1 months); median PFS was 1.5 months, and median OS was 5.6 months in CC (median follow-up = 17.1 months). The most common toxicities reported were mild to moderate asthenia, nausea, vomiting and diarrhea. Despite PM00104 showing mostly mild, predictable, manageable and reversible toxicity, protocol criteria for further recruitment were not met in EC, a futility analysis was done and recruitment was stopped; a low patient recruitment rate together with no evidence of activity in CC resulted in early study closure.