2568 Background: PM00104 is a novel synthetic alkaloid related to the marine compounds jorumycin and renieramycins. Preliminary preclinical studies suggest changes in cell cycle and DNA binding properties and transcriptional inhibition as main mechanisms of action. PM00104 has shown broad in vitro and in vivo anti-tumor activity (IC50 ≤ 10-8 M) with an acceptable toxicology profile.
METHODS
The aim of this phase I study was to assess the safety profile, dose-limiting toxicities (DLT), maximum tolerated dose (MTD), recommended dose (RD), pharmacokinetics (PK), relationship between PK and pharmacodynamics (PD) and anti-tumor activity of PM00104 administered as a 24-hour i.v. infusion q3w. Sequential cohorts of 3-6 pts were treated at 133, 266, 400, 800, 900, 1600, 3200, 4000 and 5000 μg/m2.
RESULTS
Twenty nine pts have been treated (18 male, 11 female; median age: 59, range: 44-78; ECOG PS ≤2). Five pts developed DLTs: 2 pts at 5000 μg/m2 (grade 4 thrombocytopenia/neutropenia and grade 3 nausea/vomiting in 1 pt; and grade 3 nausea in 1 pt); 1 at 4000 μg/m2 (grade 4 neutropenia/thrombocytopenia and grade 3 asthenia); 1 at 3200 μg/m2 (grade 3 tumor pain) and 1 at 266 μg/m2 (grade 3 transaminase increase). The MTD was reached at 5000 μg/m2 and the RD at 4000 μg/m2. At the RD 6 more pts have been included in order to further evaluate the safety profile and anti-tumor activity. Other adverse events included nausea and vomiting (more frequent at doses ≥800 μg/m2), fatigue, anorexia and diarrhea; most of them being of ≤grade 2 severity. No objective responses were seen but 3 pts with pancreatic adenocarcinoma, hepatocarcinoma and lower esophagus adenocarcinoma presented stable disease lasting >3 months. PM00104 shows a dose-proportional PK profile, the half-life being 20-30 hours and the volume of distribution around 1000 L.
CONCLUSIONS
PM00104 has shown an acceptable safety profile with signs of anti-tumor activity in pts with advanced malignancies when administered as a 24-hour i.v. infusion q3w. PM00104 is also being evaluated with other administration schedules as monotherapy and in combination with other anti-tumor agents. [Table: see text].