Phase I and pharmacodynamic study of the oral MEK inhibitor CI-1040 in patients with advanced malignancies.
OBJECTIVE
This phase I study was undertaken to define the toxicity, pharmacokinetics, pharmacodynamics, maximum tolerated dose (MTD), and clinical activity of CI-1040, a small-molecule inhibitor of the dual-specificity kinases MEK(mitogen-activated protein kinase kinase) -1 and MEK2 , in patients with advanced malignancy.


METHODS
CI-1040 was tested in multiple daily dosing frequencies administered for 21 days repeated every 28 days leading ultimately to continuous administration, and effect of food on absorption was tested. Single dose and steady-state pharmacokinetics were assessed during cycle 1 and phosphorylated extracellular receptor kinase (pERK) levels were assessed in WBCs and also in tumor tissue from selected patients.


RESULTS
Seventy-seven patients received CI-1040 at dose levels ranging from 100 mg QD to 800 mg tid. Grade 3 asthenia was dose limiting at the highest dose level tested, 800 mg tid administered with food. Ninety-eight percent of all drug-related adverse events were grade 1 or 2 in severity; most common toxicities included diarrhea, asthenia, rash, nausea, and vomiting. Plasma concentrations of CI-1040 and its active metabolite, PD 0184264, increased in a less than dose proportional manner from 100 to 800 mg QD. Administration with a high-fat meal resulted in an increase in drug exposure. The MTD and recommended phase II dose was 800 mg BID administered with food. Sixty-six patients were assessable for response. One partial response was achieved in a patient with pancreatic cancer and 19 patients (28%) achieved stable disease lasting a median of 5.5 months (range, 4 to 17 months). Inhibition of tumor pERK (median, 73%; range, 46% to 100%) was demonstrated in 10 patients.


CONCLUSIONS
CI-1040 was well tolerated at 800 mg BID administered with food. Both target suppression and antitumor activity were demonstrated in this phase I study.
Lorusso
Patricia M
PM
Barbara Ann Karmanos Cancer Institute, 4100 John R 4 HWCRC, Room 4206, Detroit, MI 48201, USA. lorussop@Karmanos.org
Adjei
Alex A
AA
Varterasian
Mary
M
Gadgeel
Shirish
S
Reid
Joel
J
Mitchell
David Y
DY
Hanson
Lorelei
L
DeLuca
Pamela
P
Bruzek
Laura
L
Piens
Jill
J
Asbury
Peggy
P
Van Becelaere
Keri
K
Herrera
Roman
R
Sebolt-Leopold
Judith
J
Meyer
Mark B
MB
D000284:Administration, Oral; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001549:Benzamides / Q000009:adverse effects / Q000493:pharmacokinetics / Q000627:therapeutic use*; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000009:adverse effects / Q000493:pharmacokinetics / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D048369:MAP Kinase Kinase 1 / Q000037:antagonists & inhibitors*; D048370:MAP Kinase Kinase 2 / Q000037:antagonists & inhibitors*; D008297:Male; D020714:Maximum Tolerated Dose; D008875:Middle Aged; D009362:Neoplasm Metastasis / Q000188:drug therapy*; D009369:Neoplasms / Q000097:blood / Q000188:drug therapy*; D016896:Treatment Outcome
C120227:2-(2-chloro-4-iodophenylamino)-N-cyclopropylmethoxy-3,4-difluorobenzamide; D001549:Benzamides; D004791:Enzyme Inhibitors; C482128:MAP2K2 protein, human; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D048369:MAP Kinase Kinase 1; D048370:MAP Kinase Kinase 2; C482125:MAP2K1 protein, human