A phase I and pharmacokinetic study of the selective, non-peptidic inhibitor of matrix metalloproteinase BAY 12-9566 in combination with etoposide and carboplatin.

Matrix metalloproteinases (MMPs) are zinc-dependent endopeptidases that degrade the extracellular matrix during the processes of invasion, metastasis and angiogenesis. BAY 12-9566 (BAY) is a selective, non-peptidic biphenyl inhibitor of MMPs, with nanomolar inhibitory activity against MMP-2, -3 and -9, and anti-invasive, anti-metastatic and anti-angiogenic activity in a variety of tumor models. This phase I study of oral BAY was conducted to evaluate the safety and pharmacokinetics of BAY when administered in combination with etoposide (VP-16) or in combination with VP-16 and carboplatin (CBDCA) in subjects with advanced cancer. The first cohort of patients (n=8) received a cycle of VP-16, 60 mg/m, followed 1 week later by a fixed daily oral dose of BAY, 800 mg b.i.d., to which three potential possible doses of VP-16 (low dose: 60 mg/m; mid dose: 90 mg/m; high dose: 120 mg/m) were added every 3 weeks as tolerated. The second cohort (n=5) received VP-16 (120 mg/m) and CBDCA (AUC=5) followed 1 week later by a fixed daily oral dose of BAY (800 mg) b.i.d., to which VP-16 (120 mg/m) and CBDCA (AUC=5) were added. Dose-limiting toxicity (DLT) was defined as toxicity grade 3 or above. Maximum tolerated dose was declared if two or more patients experienced DLT. A performance status of 0-2 and acceptable organ function were required for eligibility. Plasma concentrations of BAY and VP-16 were measured to investigate pharmacokinetic interactions. Eight eligible patients with a variety of tumor types (median age 64 years, range 44-76) were enrolled in the first cohort, six of who whom completed all three levels of VP-16. Progressive disease occurred in five of the eight patients; three patients continued on study with treatment. Drug level and pharmacokinetics analysis of BAY and VP-16 were also determined. The combination of BAY and VP-16 was tolerable in the first cohort, permitting enrollment of the second cohort. In the second cohort (n=5), the combination of BAY, VP-16 and CDBCA was intolerable at the doses used due to excessive hematologic toxicity in the first five patients enrolled. Pharmacokinetics and toxicity analysis was performed for this group of patients. Only Level 1 of treatment was completed for Cohort II. At this point the study was halted due to toxicity and the results of an interim analysis that failed to demonstrate sufficient clinical activity of this compound in other clinical trials. We conclude that the combination of BAY and VP-16 was well tolerated. However, the combination of BAY, VP-16 and CDBCA produces significant hematologic toxicity. Findings from this study may help to direct further studies with other inhibitors of MMPs.