binimetinib and Retinal-Detachment

Binimetinib is a potent, selective MEK1/2 inhibitor with demonstrated efficacy against BRAF- and RAS-mutant tumors. Retinal adverse events associated with MEK inhibitors have been reported in some cases. The aim of this study was to assess single-agent binimetinib, with detailed ophthalmologic monitoring, in Japanese patients with advanced solid tumors.. This was an open-label phase I dose-escalation and dose-expansion study (NCT01469130). Adult patients with histologically confirmed, evaluable, advanced solid tumors were enrolled and treated with binimetinib 30 or 45 mg twice daily (BID). The primary objective was to determine the maximum tolerated dose (MTD) and/or recommended phase II dose (RP2D) of single-agent binimetinib in Japanese patients.. Twenty-one patients were enrolled; 3 and 8 patients had documented BRAF and KRAS mutations, respectively. Two of 6 patients (33 %) receiving binimetinib 45 mg BID in dose-escalation experienced recurrent grade 2 retinal adverse events (AEs) which were reversible, and this dose was declared the MTD and RP2D. All patients experienced ≥1 AE suspected to be treatment related; the most common (>50 %) were blood creatine phosphokinase increase (76 %), retinal detachment and aspartate aminotransferase increase (62 % each), and diarrhea (52 %). There were no complete or partial responses; 14 patients (67 %) had stable disease, which lasted >180 days in 5 patients. Expression of phospho-ERK decreased in the skin following binimetinib treatment at both dose levels, indicating target inhibition.. Binimetinib demonstrated efficacy and acceptable safety in Japanese patients with solid tumors, supporting the 45 mg BID dose of binimetinib as the RP2D.

Topics: Adult; Aged; Antineoplastic Agents; Benzimidazoles; Dose-Response Relationship, Drug; Drug Administration Schedule; Female; Humans; Japan; Male; MAP Kinase Kinase 1; MAP Kinase Kinase 2; Maximum Tolerated Dose; Middle Aged; Mutation; Neoplasms; Proto-Oncogene Proteins B-raf; Proto-Oncogene Proteins p21(ras); Retinal Detachment

The patient was a 72-year-old man with a chief complaint of abdominal pain. We performed laparoscopic left hemicolectomy of the colon after descending colon cancer ileus stenting, and postoperative pathology was pT4aN0M0, pStage Ⅱb. In 1.5 years postoperatively, 2 liver metastases and 1 lymph node metastasis were found, and each was resected. Chemotherapy was initiated for multiple lung metastases. Genetic testing was positive for BRAF V600E mutation, and the patient received 8 mFOLFOXIRI plus bevacizumab therapy courses. After 15 5-FU plus LV plus bevacizumab courses, the patient had a brain infarction and lung metastasis reincreased. Chemotherapy was changed to encorafenib plus binimetinib plus cetuximab. On day 2, visual impairment was observed, and serous retinal detachment CTCAE Grade 2 was diagnosed. On day 7, the symptoms improved and one-step dose reduction was resumed. On day 2 of re-treatment, serous retinal detachment recurred and treatment was discontinued. On day 4 of re-treatment, the symptoms improved, another dose reduction was performed, and treatment was resumed. Since subjective MEK inhibitor-induced ocular symptoms are often minor, conducting an interview and early ophthalmologic diagnosis is recommended.

Topics: Aged; Antineoplastic Combined Chemotherapy Protocols; Bevacizumab; Cetuximab; Colorectal Neoplasms; Fluorouracil; Humans; Male; Mitogen-Activated Protein Kinase Kinases; Mutation; Neoplasm Recurrence, Local; Proto-Oncogene Proteins B-raf; Retinal Detachment

To investigate the clinical and morphologic characteristics of serous retinal disturbances in patients taking mitogen-activated protein kinase kinase (MEK) inhibitors.. A total of 313 fluid foci in 50 eyes of 25 patients receiving MEK inhibitors for treatment of their metastatic cancer, who had evidence of serous retinal detachments confirmed by optical coherence tomography (OCT).. Single-center, retrospective cohort study.. Clinical examination and OCT were used to evaluate MEK inhibitor-associated subretinal fluid. The morphology, distribution, and location of fluid foci were serially evaluated for each eye. Choroidal thickness was measured at each time point (baseline, fluid accumulation, and fluid resolution). Two independent observers performed all measurements. Statistical analysis was used to correlate interobserver findings and compare choroidal thickness and visual acuity at each time point.. Comparison of OCT characteristics of retinal abnormalities at baseline to fluid accumulation.. The majority of patients had fluid foci that were bilateral (92%) and multifocal (77%) and at least 1 focus involving the fovea (83.3%). All fluid foci occurred between the interdigitation zone and an intact retinal pigment epithelium. The 313 fluid foci were classified into 4 morphologies, as follows: 231 (73.8%) dome, 36 (11.5%) caterpillar, 31 (9.9%) wavy, and 15 (4.8%) splitting. Best-corrected visual acuity at fluid resolution was not statistically different from baseline; and no eye lost more than 2 Snellen lines from baseline at the time of fluid accumulation. There was no statistical difference in the choroidal thickness between the different time points (baseline, fluid accumulation, and fluid resolution). A strong positive interobserver correlation was obtained for choroidal thickness measurements (r = 0.97, P < 0.0001) and grading of foci morphology (r = 0.97, P < 0.0001).. The subretinal fluid foci associated with MEK inhibitors have unique clinical and morphologic characteristics, which can be distinguished from the findings of central serous chorioretinopathy. In this series, MEK inhibitors did not cause irreversible loss of vision or serious eye damage.

Topics: Adult; Aged; Aged, 80 and over; Antineoplastic Agents; Azetidines; Benzimidazoles; Central Serous Chorioretinopathy; Female; Fluorescein Angiography; Humans; Male; Middle Aged; Mitogen-Activated Protein Kinase Kinases; Neoplasms; Piperidines; Protein Kinase Inhibitors; Pyridones; Pyrimidinones; Retinal Detachment; Retrospective Studies; Subretinal Fluid; Tomography, Optical Coherence; Visual Acuity; Young Adult

MEK inhibitor chemotherapy, used in various malignancies, has been reported to be associated with serous retinal detachments. This study reports serial multimodal imaging focused primarily on infrared reflectance and spectral-domain optical coherence tomography (SD-OCT) in the monitoring of MEK inhibitor retinal toxicity. The benefit of OCT angiography in understanding the pathophysiology of MEK inhibitor toxicity is also shown.

Topics: Antineoplastic Combined Chemotherapy Protocols; Benzimidazoles; Female; Fluorescein Angiography; Follow-Up Studies; Humans; MAP Kinase Kinase 1; MAP Kinase Kinase 2; Middle Aged; Multimodal Imaging; Optical Imaging; Ovarian Neoplasms; Phosphoinositide-3 Kinase Inhibitors; Retina; Retinal Detachment; Thiazoles; Tomography, Optical Coherence