RESUMEN
This phase 1 first-in-human study evaluated the safety, tolerability, and pharmacokinetics of MK-1088, a novel, small-molecule dual inhibitor of adenosine A2A and A2B receptors. Healthy adult participants were enrolled in two panels (n = 8 each) and randomly assigned to receive MK-1088 (n = 6) or placebo (n = 2) orally in each of five treatment periods. Participants in panel A received single ascending doses of MK-1088 at 1, 10, 50, and 150 mg or placebo in a fasted or fed (50 mg only) state. Participants in panel B received MK-1088 at 3, 25, 100, and 224 mg or placebo in a fasted state. Primary objectives were to evaluate safety, tolerability, and plasma pharmacokinetics following a single dose of MK-1088. The secondary objective was to evaluate the effects of a high-fat meal on pharmacokinetics. All participants (n = 16) completed the study (median age: 33 years [range: 20-43]; all were male). Treatment-related adverse events (AEs) occurred in 1 of 6 (17%), 4 of 6 (67%), 4 of 6 (67%), and 2 of 6 (33%) participants after receiving MK-1088 at 3, 25, 100, and 224 mg, respectively. No serious AEs or deaths due to any cause occurred. MK-1088 was rapidly absorbed after a single dose; half-life was ~ 11 h in the 100-224 mg dose range. The target concentration at 12 h (> 0.3 µM) was exceeded at the 50-mg dose level. MK-1088 plasma pharmacokinetics increased dose proportionately. A high-fat meal did not significantly affect pharmacokinetics at the 50-mg dose. MK-1088 was well tolerated and demonstrated dose-proportional pharmacokinetic properties that were not affected by a high-fat meal.
RESUMEN
BACKGROUND: Pembrolizumab, a monoclonal antibody against PD-1, has shown limited efficacy in patients with microsatellite stable or mismatch repair proficient (MSS/pMMR) metastatic colorectal cancer (CRC). We evaluated vicriviroc (small-molecule C-C motif chemokine ligand 5 antagonist) plus pembrolizumab in patients with advanced or metastatic MSS/pMMR CRC. PATIENTS AND METHODS: This open-label, phase 2 trial (NCT03631407) enrolled adults with histologically confirmed, locally advanced, unresectable or metastatic CRC that was MSS per local assessment. All patients had received previous treatment with standard therapies. Patients were randomized 1:1 to vicriviroc 150 mg orally once daily plus pembrolizumab 200 mg intravenously every 3 weeks or vicriviroc 250 mg orally once daily plus pembrolizumab 200 mg intravenously every 3 weeks for up to 35 cycles (2 years). Primary endpoints were the objective response rate (ORR) as assessed by the investigator per RECIST v1.1, dose-limiting toxicities (DLTs), adverse events (AEs), and discontinuations due to AEs. RESULTS: Forty patients were enrolled and treated. ORR was 5% (95% CI, 0.1%-24.9%) in both treatment groups. There were no complete responses; 1 patient in each treatment group experienced a partial response. No patient in the vicriviroc 150 mg plus pembrolizumab group experienced a DLT. Two patients in the vicriviroc 250 mg plus pembrolizumab group experienced DLTs (1 grade 4 encephalopathy and 1 grade 4 pneumonitis). CONCLUSION: The combination of vicriviroc at doses of 150 or 250 mg plus pembrolizumab 200 mg showed limited antitumor activity in patients with advanced or metastatic MSS/pMMR CRC. Toxicity with the combination was manageable.