A proposed interim analysis of the high C-reactive protein (CRP) subgroup showed that ruxolitinib plus regorafenib did not demonstrate a sufficient level of efficacy to warrant continuation.
Incyte chief medical officer Steven Stein said: "We are disappointed at the outcome from this interim analysis and deeply grateful for the support and commitment of the patients participating in the study, their families, and the study investigators."
Ruxolitinib (Jakafi) is a first-in-class JAK1/JAK2 inhibitor approved by the US Food and Drug Administration (FDA) to treat people with polycythemia vera, a disorder of the bone marrow, who have had an inadequate response to or are intolerant of hydroxyurea.
It is also indicated to treat people with intermediate or high-risk myelofibrosis (MF), including primary MF, post-polycythemia vera MF, and post-essential thrombocythemia MF.
The phase 2 double-blind study of patients with relapsed or refractory metastatic CRC included an open-label, safety run-in and a randomized phase.
The open-label phase was carried out to confirm the safety of the ruxolitinib and regorafenib combination in patients with relapsed or refractory metastatic CRC
The randomized phase included 2 sub-studies targeting separate populations of patients with CRC depending on the levels of systemic inflammation, as measured by the modified Glasgow Prognostic Score.
Subjects in each sub-study were randomized 1:1 to receive ruxolitinib and regorafenib or regorafenib plus placebo.