Phase I study of carboplatin in combination with PM00104 (Zalypsis®) in patients with advanced solid tumors

This phase I trial determined the recommended dose for phase II trials (RD) of carboplatin 1-h intravenous (i.v.) infusion followed by PM00104 1-h i.v. infusion on Day 1 every 3 weeks (q3wk) in adult patients with advanced solid tumors. A toxicity-guided, dose-escalation design was used. Patients were stratified and divided into heavily (n = 6) or mildly pretreated (n = 14) groups. Transient grade 4 thrombocytopenia (in one heavily and three mildly pretreated patients) was the only dose-limiting toxicity (DLT) observed. Carboplatin AUC3-PM00104 2.0 mg/m(2) was the RD in both groups. At this RD, the carboplatin AUC was equal to ~60 % the target AUC used in other combinations, and the PM00104 dose intensity was 56-67 % of the value achieved at the RD for single-agent PM00104 given as 1-h infusion q3wk. Most treatment-related adverse events were grade 1/2. They mainly consisted of gastrointestinal and general symptoms, such as fatigue, anorexia, mucosal inflammation or nausea. Transient neutropenia (50 % of patients) and thrombocytopenia (33-38 %) were the most common severe hematological abnormalities; their incidence was higher than with single-agent PM00104. No pharmacokinetic drug-drug alterations occurred. Partial response was found in one patient with triple negative breast cancer pretreated with paclitaxel/bevacizumab. Three patients with colorectal cancer, head and neck cancer, and tumor of unknown origin had disease stabilization for ≥3 months. In conclusion, no optimal dose was reached due to overlapping myelosuppression despite stratification according to prior treatment. Therefore, this carboplatin plus PM00104 combination was not selected for further clinical research.

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.

First-in-man phase I trial of two schedules of the novel synthetic tetrahydroisoquinoline alkaloid PM00104 (Zalypsis) in patients with advanced solid tumours

Background:

PM00104 binds guanines at DNA minor grooves, impacting DNA replication and transcription. A phase I study was undertaken to investigate safety, dose-limiting toxicities (DLTs), recommended phase II dose (RP2D), pharmacokinetics (PKs) and preliminary antitumour activity of PM00104 as a 1- or 3-h infusion three-weekly.

Methods:

Patients with advanced solid tumours received PM00104 in a dose escalation trial, as guided by toxicity and PK data.

Results:

A total of 47 patients were treated; 27 patients on the 1-h schedule (0.23–3.6 mg m⁻²) and 20 patients on the 3-h schedule (1.8–3.5 mg m⁻²). Dose-limiting toxicities comprised reversible nausea, vomiting, fatigue, elevated transaminases and thrombocytopenia, establishing the 1-h schedule RP2D at 3.0 mg m⁻². With the 3-h schedule, DLTs of reversible hypotension and neutropenia established the RP2D at 2.8 mg m⁻². Common PM00104-related adverse events at the RP2D comprised grade 1–2 nausea, fatigue and myelosuppression. In both schedules, PKs increased linearly, but doses over the 1-h schedule RP2D resulted in higher than proportional increases in exposure. A patient with advanced urothelial carcinoma had RECIST shrinkage by 49%, and three patients had RECIST stable disease ⩾6 months.

Conclusion:

PM00104 is well tolerated, with preliminary evidence of antitumour activity observed. The 1-h 3-weekly schedule is being assessed in phase II clinical trials.

Phase I study of PM00104 (Zalypsis®) administered as a 1-hour weekly infusion resting every fourth week in patients with advanced solid tumors

PM00104 (Zalypsis®) is a new synthetic alkaloid with potent cytotoxic activity against tumor cell lines. This phase I clinical trial determined the maximal tolerated dose (MTD) and recommended dose (RD) for phase II trials of PM00104 administered as a 1-hour intravenous (i.v.) infusion weekly for three consecutive weeks resting every fourth week (d1,8,15 q4wk). Forty-nine patients with advanced solid malignancies received PM00104 following a toxicity-guided, accelerated, dose-escalation design. Doses evaluated ranged from 0.07 to 3.0 mg/m(2). Dose-limiting toxicities (DLTs) appeared at the highest doses tested and comprised grade 3 diarrhea and grade 4 lipase increase at 2.0 mg/m(2); grade 1 thrombocytopenia and grade 2 neutropenia with two infusion omissions, grade 3 fatigue and grade 4 febrile neutropenia at 2.5 mg/m(2); and grade 3/4 fatigue, grade 4 neutropenia lasting >5 days and grade 4 thrombocytopenia at 3.0 mg/m(2). RD was established at 2.0 mg/m(2). PM00104-related adverse events at the RD were mostly grade 1/2, with fatigue, nausea and vomiting as the most common. Transient and manageable myelosuppression and transaminase increases were also reported. Main pharmacokinetic parameters increased linearly with dose. Disease stabilization lasting ≥ 3 months was found in 4 patients with cervical carcinoma, colorectal adenocarcinoma, lachrymal adenoid carcinoma, and bladder carcinoma (n=1 each). In conclusion, PM00104 2.0 mg/m(2) 1-hour, d1,8,15 q4wk showed a positive risk-benefit ratio, which has supported its further evaluation in three ongoing phase II clinical trials.