A Phase IIa Study of the MEK Inhibitor Trametinib Monotherapy in the Treatment of Biliary Tract Cancers

Per Response Evaluation Criteria In Solid Tumors Criteria (RECIST v1.1) for target lesions and assessed by CT or MRI: Complete Response (CR), Disappearance of all target lesions; Partial Response (PR), >=30% decrease in the sum of the diameters of target lesions; Stable Disease(SD), Neither sufficient shrinkage to qualify for PR nor sufficient increase to qualify for PD; Progressive Disease(PD), At least a 20% increase in the sum of the diameters of target lesions. Non-PD = CR + PR + SD.

Twelve week non-progressive disease (PD) at Week 12 was evaluated by computed tomography. Non- PD was calculated as the sum of complete response (CR), partial response (PR), and stable disease (SD).

An AE is any untoward medical occurrence in a clinical investigation participant, temporally associated with the use of a medicinal product, whether or not considered related to the medicinal product. An SAE is any untoward medical occurrence that, at any dose results in death, is life-threatening, requires hospitalization or prolongation of existing hospitalization, results in disability/incapacity, is a congenital anomaly/birth defect or Protocol-Specific SAEs

Interstitial lung disease markers KL-6 assessments were carried out at Baseline (Day 1), Week 12, Week 20, Week 24, Week 28, Week 32, and Week 36

Interstitial lung disease marker Surfactant Protein D assessments were carried out at Baseline (Day 1), Week 12, and Week 28

Shift from baseline was calculated as the post baseline value minus the baseline value for albumin, alkalaine phosphatase (AP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), bilirubin, creatine kinase (CK), creatinine, hypercalcemia, hyperglycemia, hyperkalemia, hypermagnesemia, hypernatremia, hypocalcemia, hypoglycemia, hypokalemia, hypomagnesemia, hyponatremia, and phosphate. A Worst Post Baseline (WPB) grade shift is defined as the worst change that occurred at any measured timepoint during the treatment period. Grading was determined by the NCI Common Terminology Criteria for Adverse Events Version 3.0 (NCI-CTCAE). Participants with missing baseline grade were designated a baseline grade of 0.

Shift from baseline was calculated as the post baseline value minus the baseline value for activated partial thromboplastin time (APTT) and prothrombin time (PT). A Worst Post Baseline (WPB) grade shift is defined as the worst change that occurred at any measured timepoint during the treatment period. Grading was determined by the NCI Common Terminology Criteria for Adverse Events Version 3.0 (NCI-CTCAE). Participants with missing baseline grade were designated a baseline grade of 0.

Shift from baseline was calculated as the post baseline value minus the baseline value for hemoglobin, lymphocytes, neutrophils, platelets, and leukocytes. A Worst Post Baseline (WPB) grade shift is defined as the worst change that occurred at any measured timepoint during the treatment period. Grading was determined by the NCI Common Terminology Criteria for Adverse Events Version 3.0 (NCI-CTCAE). Participants with missing baseline grade were designated a baseline grade of 0.

Change from baseline was calculated as the post baseline value minus the baseline value for cancer antigen 19-9 (CA 19-9), chloride, lactate dehydrogenase (LDH), and urea. A Worst Post Baseline (WPB) change is defined as the worst change that occurred at any measured timepoint during the treatment period. Measurements were designated as either Decreased to Low (DTL) or Increased to High (ITH) or Change to Normal/No Change (CN/NC). Participants with missing baseline measurements or visit measurements were considered to be missing. Participants were counted twice if the participant Decreased to Low and Increased to High.

Change from baseline was calculated as the post baseline value minus the baseline value for prothrombin time (PT). A Worst Post Baseline (WPB) change is defined as the worst change that occurred at any measured timepoint during the treatment period. Measurements were designated as either Decreased to Low (DTL) or Increased to High (ITH) or Change to Normal/No Change (CN/NC). Participants with missing baseline measurements or visit measurements were considered to be missing. Participants were counted twice if the participant Decreased to Low and Increased to High.

Change from baseline was calculated as the post baseline value minus the baseline value for basophils, eosinophils, and monocytes. A Worst Post Baseline (WPB) change is defined as the worst change that occurred at any measured timepoint during the treatment period. Measurements were designated as either Decreased to Low (DTL) or Increased to High (ITH) or Change to Normal/No Change (CN/NC). Participants with missing baseline measurements or visit measurements were considered to be missing. Participants were counted twice if the participant Decreased to Low and Increased to High.

Change from baseline was calculated as the post baseline value minus the baseline value for carcinoembryonic antigen (CEA). A Worst Post Baseline (WPB) change is defined as the worst change that occurred at any measured timepoint during the treatment period. Measurements were designated as either Decreased to Low (DTL) or Increased to High (ITH) or Change to Normal/No Change (CN/NC). Participants with missing baseline measurements or visit measurements were considered to be missing. Participants were counted twice if the participant Decreased to Low and Increased to High.

Body temperature was categorized as Decrease to <=35; Change to Normal or No Change and Increase to >=38. Change from baseline was calculated as the post baseline value minus the baseline value. A Worst Post Baseline (WPB) change is defined as the worst change that occurred at any measured timepoint during the treatment period. Participants with missing baseline measurements or visit measurements were considered to be missing.

Systolic and diastolic blood pressure was measured after sitting for at least 5 minutes. Systolic blood pressure (SBP) was categorized as: Grade 0 (<120), Grade 1 (>=120-<140), Grade 2 (>=140-<160) and Grade 3 (>=160). Diastolic blood pressure (DBP) was categorized as Grade 0 (<80), Grade 1 (>=80-<90), Grade 2 (>=90-<100), and Grade 3 (>=100). Change from baseline was calculated as the post baseline value minus the baseline value. A Worst Post Baseline (WPB) change is defined as the worst change that occurred at any measured timepoint during the treatment period. Participants with missing baseline measurements or visit measurements were considered to be missing.

Pulse rate was categorized as Decrease to <60, Change to Normal or No Change, and Increase to >100. Change from baseline was calculated as the post baseline value minus the baseline value. A Worst Post Baseline (WPB) change is defined as the worst change that occurred at any measured timepoint during the treatment period. Participants with missing baseline measurements or visit measurements were considered to be missing.

Oxygen Saturation was measured at Baseline (Day 1), Week 4, Week 8, Week 12, Week 16, Week 20, Week 24, Week 28, Week 32 and Week 36. For records occurring after baseline, change from baseline was calculated as the post baseline value minus the baseline value. When either the baseline or visit value was missing, the change from baseline was considered to be missing.

Progression-Free Survival (PFS) is defined as the interval of time (in weeks) between the date of randomization and the earlier of the date of disease progression and the date of death due to any cause. Disease progression was based on the assessments by the Investigator. If a participant received subsequent anti-cancer therapy prior to the date of documented progression or death, PFS in the participant was censored at the last adequate assessment prior the initiation of the new anti-cancer therapy. Otherwise, if a participant did not have a documented date of progression or death, PFS in the participant was censored at the last adequate assessment.

Progression-Free Survival (PFS) is defined as the interval of time (in weeks) between the date of randomization and the earlier of the date of disease progression and the date of death due to any cause. Disease progression was based on the assessments by the independent radiologist. If a participant received subsequent anti-cancer therapy prior to the date of documented progression or death, PFS in the participant was censored at the last adequate assessment prior the initiation of the new anti-cancer therapy. Otherwise, if a participant did not have a documented date of progression or death, PFS in the participant was censored at the last adequate assessment.

Overall Survival (OS) is defined as the interval of time (in weeks) between the date of randomization and the date of death due to any cause. For participants that did not die, time of death was censored at the date of last contact. The date of death was taken from that recorded on the Record of Death page. Death on study due to any cause was included. One year OS was calculated from Kaplan-Meier estimates.

Overall Response Rate (ORR) is defined as the number of participants achieving a confirmed CR or PR per RECIST 1.1 criteria from the start of treatment until disease progression or the start of new anti-cancer therapy. ORR was based on responses from the Investigator assessment of best overall response, the best overall response is the best response recorded from the start of the treatment until disease progression/recurrence. ORR is calculated as CR + PR.

Overall Response Rate (ORR) is defined as the number of participants achieving a confirmed CR or PR per RECIST 1.1 criteria from the start of treatment until disease progression or the start of new anti-cancer therapy. ORR was based on responses from the Independent Radiologist assessment of best overall response, the best overall response is the best response recorded from the start of the treatment until disease progression/recurrence. ORR is calculated as CR + PR.

Time to response (TTR) event was defined as achievement of a confirmed CR or PR, as the time from date of randomization until date of first documented evidence of CR or PR (whichever status is recorded first). If a participant received subsequent anti-cancer therapy prior to the date of documented progression or death, progression free survival (PFS) in the participant was censored at the last adequate assessment prior the initiation of the new anti-cancer therapy. Otherwise, if a participant did not have a documented date of progression or death, PFS in the participant was censored at the last adequate assessment.

Time to response (TTR) event was defined as achievement of a confirmed CR or PR, as the time from date of randomization until date of first documented evidence of CR or PR (whichever status is recorded first). If a participant received subsequent anti-cancer therapy prior to the date of documented progression or death, progression free survival (PFS) in the participant was censored at the last adequate assessment prior the initiation of the new anti-cancer therapy. Otherwise, if a participant did not have a documented date of progression or death, PFS in the participant was censored at the last adequate assessment. Only 1 participant reached PR therefore estimated time to response cannot be presented. The time to response for this patient is presented as the actual number of weeks to PR.

Duration of response was summarized for participants with a confirmed CR or PR and is defined as the time (in weeks) from the initial response (CR/PR) to first documented disease progression or death due to any cause. If a participant received subsequent anti-cancer therapy prior to the date of documented progression or death, PFS in the participant was censored at the last adequate assessment prior the initiation of the new anti-cancer therapy. Otherwise, if a participant did not have a documented date of progression or death, PFS in the participant was censored at the last adequate assessment.

Duration of response was summarized for participants with a confirmed CR or PR and is defined as the time (in weeks) from the initial response (CR/PR) to first documented disease progression or death due to any cause. If a participant received subsequent anti-cancer therapy prior to the date of documented progression or death, PFS in the participant was censored at the last adequate assessment prior the initiation of the new anti-cancer therapy. Otherwise, if a participant did not have a documented date of progression or death, PFS in the participant was censored at the last adequate assessment.