MEK inhibitor-associated retinopathy (MEKAR) in metastatic melanoma: Long-term ophthalmic effects

Targeted treatment for craniopharyngioma

INTRODUCTION

Craniopharyngioma is a rare solid-cystic tumor of the hypothalamopituitary region. Two distinct craniopharyngioma types (formerly subtypes), adamantinomatous and papillary, have been described. These tumors often manifest with neuroendocrine dysfunction, vision problems, hydrocephalus, and cognitive changes. Despite efforts to spare vital brain structures, conventional treatments such as surgery and radiation can exacerbate preceding deficits and contribute to permanent neurologic impairment. Recent studies have identified BRAF-V600E mutations in nearly all papillary craniopharyngiomas (PCP), and CTNNB1/Wnt pathway alterations in adamantinomatous craniopharyngiomas (ACP). These discoveries have advanced our understanding of craniopharyngioma pathogenesis and have opened opportunities for targeted biological treatments.

PURPOSE

The primary objective of this article is to review the current landscape of targeted treatments in papillary and adamantinomatous craniopharyngioma.

RESULTS

Treatment of PCP with BRAF/MEK inhibition has demonstrated durable tumor response in the adjuvant and neoadjuvant settings in multiple case studies and one phase II clinical trial. Although treatment advances are more limited for ACP, CTNNB1/Wnt pathway inhibitors showed promising results in pre-clinical studies and are under continued investigation.

CONCLUSION

The efficacy of BRAF/MEK inhibition in PCP supports the use of targeted therapy in patients with newly diagnosed PCP. The optimal targeted treatment combinations and their timing, duration, long-term effects, and sequencing with traditional therapeutic modalities have not been established and warrant further study. Targeted therapies represent a significant advancement in the field of oncology, and craniopharyngiomas are viable candidates for these approaches pending further research.

Pediatric MEK inhibitor-associated retinopathy: 8-year experience at a tertiary academic center and report of 2 cases

BACKGROUND

An adverse effect of mitogen-activated protein kinase (MEK) inhibitors is MEK inhibitor-associated retinopathy (MEKAR), a fluid collection between the retinal pigment epithelium (RPE) and interdigitation zone (IZ) seen in up to 90% of adults taking these medications. MEKAR is not well described in children. The purpose of this study was to characterize MEKAR screening practices, identify cases of MEKAR, and describe their clinical presentations in children.

METHODS

We conducted a retrospective study at our tertiary care pediatric hospital, examining pediatric patients who underwent MEK inhibitor (MEK-i) therapy between 2015 and 2023. We describe 2 cases of pediatric MEKAR that arose during the study period.

RESULTS

Of 152 patients identified, 104 met inclusion criteria. Trametinib was the most used MEK-i, with plexiform neurofibroma being the predominant indication for therapy. Optical coherence tomography macula screenings were predominantly performed in clinic, with varying screening intervals (mean, 9.85 months; median, 6.5 months). We identified 2 cases of pediatric MEKAR, both of which improved or resolved without altering MEK-i dosage. Our study suggests a lower rate of MEKAR in pediatric patients compared with adults, although limitations in screening frequency and duration may influence this observation.

CONCLUSIONS

Our findings underscore the importance of systematic MEKAR screening protocols in pediatric patients receiving MEK-i therapy, facilitating early detection and monitoring of ocular toxicity. When MEKAR develops, the risks of stopping treatment must be weighed against the risks of retinopathy, although in our patients, MEKAR resolved without alterations to their medication regimen.

Incidence and Management of Retinopathy and Uveitis in Patients Receiving BRAF/MEK Inhibitor Therapy

PURPOSE

To assess the clinical features of ocular adverse events in patients receiving BRAF/MEK inhibitor therapy.

METHODS

In this retrospective study, 65 patients were treated with BRAF/MEK inhibitors (dabrafenib/trametinib or encorafenib/binimetinib).

RESULTS

Of the 65 patients, 28 had malignant melanoma and 37 had non-melanoma malignancies. Bilateral MEK-associated retinopathy was observed in nine cases; none experienced vision loss due to MEK-associated retinopathy. Uveitis was diagnosed in four patients (6.1%), three of whom presented with Vogt-Koyanagi-Harada (VKH)-like uveitis. All VKH-like uveitis cases were observed in patients with melanoma and their incidences were significantly higher in these patients than in those without melanoma (p = .04). Treatment with corticosteroids resulted in either resolution or control of symptoms in all cases of VKH-like uveitis, enabling continuation of BRAF/MEK inhibitor therapy.

CONCLUSION

VKH-like uveitis was found to be significantly more frequent in patients with melanoma than in those with other malignancies.

Integrating MAPK pathway inhibition into standard-of-care therapy for pediatric low-grade glioma

Pediatric low-grade gliomas (pLGG) are a group of tumors largely driven by alterations in a single genetic pathway, known as the RAS-RAF-mitogen-activated protein kinase (MAPK) pathway. Recent biologic insights and therapeutic targeting of MAPK-alterations have dramatically shifted the treatment approach in pLGG. While chemotherapy remains front-line therapy for unresectable pLGG in most scenarios (with the notable exception of BRAF V600E-altered tumors), many patients recur following cytotoxic agents and require further treatment. Inhibitors of the MAPK pathway, primarily MEK and RAF kinase inhibitors, have emerged as effective and tolerable second-line or later therapy for pLGG. As familiarity with these targeted agents increases, their indications for use continue to expand and Phase 3 clinical trials investigating their utility in the front-line setting are ongoing. We have adopted mitigation strategies for their associated toxicities; skin toxicity, in particular, is now managed by prevention strategies and early dermatologic intervention. This review highlights current approaches for the clinical implementation of MEK and RAF kinase inhibitors for pLGG, focusing on the practical aspects of drug administration, toxicity management, response monitoring, and distribution to patients experiencing geographic or financial barriers to care. Additionally, we review important considerations for the off-label use of these agents while contemporaneous clinical trials assessing front-line efficacy are ongoing. We discuss the potential for more expansive or histology-agnostic tumor targeting using MEK inhibitors, harnessing their biologic relevance for other RAS-altered conditions.

Drug-related macular edema: a real-world FDA Adverse Event Reporting System database study

PURPOSE

This study aims to assess the risks associated with drug-induced macular edema and to examine the epidemiological characteristics of this condition.

METHODS

This study analyzed data from the U.S. Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS) database from January 2004 to June 2024 to conduct a disproportionality analysis identifying drugs with positive signals of drug-induced ME. Additionally, the onset time of ME associated with these drugs was examined.

RESULTS

In the FAERS database, a total of 490 drugs were reported to pose a risk of drug-induced ME. Disproportional analysis and screening further identified 8 drugs that significantly increased this risk. Among these, one is ophthalmic drugs, including Latanoprost (ROR = 5.51), and ten are non-ophthalmic drugs, including Cefuroxime (ROR = 75.93), Fingolimod (ROR = 30.69), and Siponimod (ROR = 20.51).

CONCLUSIONS

This study utilizes the FAERS database to investigate potential associations between drug use and the occurrence of ME, rapidly identify drugs that may induce the condition, and propose research strategies. These findings hold significant value for guiding clinical medication practices.

Side Effects of Novel Anticancer Drugs on the Posterior Segment of the Eye: A Review of the Literature

Currently, common treatment approaches for neoplastic diseases include surgery, radiation, and/or anticancer drugs (chemotherapy, hormone medications, and targeted therapies). In particular, anticancer medicines destroy cancerous cells by blocking certain pathways that aid in the disease's initiation and progression. These pharmaceutical drugs' capacity to inhibit malignant cells has made them indispensable in the treatment of neoplastic disorders. Nonetheless, considering their cyto- and neurotoxicity, as well as their inflammatory responses, these medications may also have unfavorable systemic and ocular side effects. In fact, it is well known that ocular posterior segment side effects, including retinal and vascular complications, have a negative influence on the patient's eyesight and quality of life. However, the underlying mechanisms contributing to the development of these side effects remain incompletely recognized, especially in the case of newly available anticancer drugs. The purpose of this literature review is to analyze the possible side effects of new anticancer drugs on the posterior segment of the eye, trying to better understand the involved pharmacological mechanisms and offer helpful guidance on their appropriate management.

Real-World Incidence of Incident Noninfectious Uveitis in Patients Treated With BRAF Inhibitors: A Nationwide Clinical Cohort Study

PURPOSE

To compare the incidence of noninfectious uveitis in skin melanoma or lung cancer patients who received BRAF inhibitors with that in those who received immune checkpoint inhibitors (ICIs) or conventional cytotoxic chemotherapy.

DESIGN

Nationwide population-based retrospective clinical cohort study METHODS: From the Health Insurance Review and Assessment Service database of South Korea, we retrospectively defined 77,323 patients with skin melanoma or lung cancer who received BRAF inhibitor therapy (BRAF inhibitor-exposed group; n = 396), ICIs (ICI-exposed group; n = 22,474), or conventional cytotoxic chemotherapy (unexposed group; n = 54,453). We calculated the 1-year cumulative incidence of noninfectious uveitis in each group from the first day of BRAF inhibitor, ICI, or cytotoxic agent administration.

RESULTS

During the first year of treatment initiation, the cumulative incidence of uveitis was 0.33%, 0.35%, and 2.27% in the unexposed, ICI-exposed, and BRAF inhibitor-exposed groups, respectively. Adjusted hazard ratios (aHR) indicated a 7.52-fold and 5.68-fold increased risk of uveitis in the BRAF inhibitor-exposed group compared with that in the unexposed and ICI-exposed groups (95% confidence interval [CI] 3.83-14.75, P < .001 and 95% CI 2.81-11.47, P < .001, respectively). After 1:4 propensity score matching, aHRs showed a 35.51-fold and 15.80-fold increased risk (95% CI 4.49-280.48, P = .001 and 95% CI 1.76-141.00, P = .014) of uveitis and severe uveitis, respectively, in the BRAF inhibitor-exposed versus unexposed patients. Crossover analysis within the BRAF inhibitor-exposed group showed a 3.71-fold increase in uveitis risk during 1-year post index date in comparison with 1-year prior to index date (95% CI 1.03-13.40, P = .046). In the BRAF inhibitor-exposed group, female sex, chronic kidney disease, and melanoma were associated with a trend of increased, albeit nonsignificant, risk of uveitis.

CONCLUSIONS

Melanoma or lung cancer patients treated with BRAF inhibitors showed significantly higher risk of noninfectious uveitis than patients treated with conventional cytotoxic drugs or ICIs. These findings emphasize the importance of pretreatment patient education on BRAF-inhibitor-associated uveitis risk to enable prompt ophthalmic evaluation and treatment if symptoms arise during drug administration.

MEK Inhibitor-Associated Ocular Hypertension

Introduction

Mitogen-activated protein kinase kinase (MEK) inhibitors are targeted anticancer agents that are prescribed to treat a broad range of cancers. Despite their strong efficacy profile, MEK inhibitors have been associated with ocular toxicities, most notably, self-limited serous detachments of the neurosensory retina. In this report, we outline 3 cases of a rarely documented toxicity, MEK inhibitor-associated ocular hypertension.

Case Presentations

In the first case, a 69-year-old female with metastatic cholangiocarcinoma presented with an intraocular pressure (IOP) of 25 mm Hg right eye (OD) and 27 mm Hg left eye (OS) 2 months after starting trametinib therapy. Similarly, in the second case, a 26-year-old female with Langerhans cell histiocytosis presented with an elevated IOP of 24 mm Hg bilaterally (OU) 13 months after beginning treatment with an investigational MEK inhibitor. In the third case, a 46-year-old male with Langerhans cell histiocytosis presented with a new onset of elevated IOP of 24 mm Hg 21 days after initiating treatment with cobimetinib. All 3 patients' IOP returned to normal following dorzolamide/timolol administration and continued their cancer therapy.

Discussion/Conclusion

This report presents 3 cases of elevated IOP in patients taking three distinct MEK inhibitors which would suggest that IOP-elevating effects exist across the class of MEK inhibitors. All 3 patients had a satisfactory response to topical pressure-lowering drops while continuing their life-preserving MEK inhibitor drug dose, indicating that discontinuation of therapy may not be necessary. Due to the increasing use of MEK inhibitors, it is important that ophthalmologists familiarize themselves with the broad range of potential adverse ocular effects of MEK inhibitors.

Incidence of Ophthalmological Complications in NF-1 Patients Treated with MEK Inhibitors

MEK inhibitors (MEKi) represent innovative and promising treatments for managing manifestations of neurofibromatosis type 1 (NF1). To mitigate potential ophthalmic side effects, such as MEKi-associated retinopathy (MEKAR), patients undergoing MEKi therapy routinely receive ophthalmology evaluations. Our study aims to assess the necessity of this regular screening within a predominantly pediatric NF1 population by examining the occurrence of ocular adverse events (OAE). A retrospective study evaluated 45 NF1 patients receiving MEKi. Inclusion criteria included baseline and follow-up examinations following the initiation of MEKi therapy. At each assessment, a comprehensive eye evaluation was performed, comprising a dilated fundus examination, ocular coherence tomography of the macula and nerve fiber layer, and Humphrey visual field testing. Twenty-six patients, with an average age of 13 years (range 2-23 years) and an average follow-up duration of 413 days were included in the analysis. Three different MEKi were used: selumetinib (77%), trametinib (23%), and mirdametinib (4%). None of the patients experienced retinopathy at any point during the study. Some patients had pre-existing optic neuropathies (27%), but no instances of nerve changes occurred after commencing MEKi therapy. Four patients (15%) exhibited symptoms of dry eye, all of which were effectively managed with topical lubrication.

A Phase 2 Study of Encorafenib in Combination with Binimetinib in Patients with Metastatic BRAF-Mutated Thyroid Cancer in Japan

Background: Driver mutations at BRAF V600 are frequently identified in papillary thyroid cancer and anaplastic thyroid cancer (ATC), in which BRAF inhibitors have shown clinical effectiveness. This Japanese phase 2 study evaluated the efficacy and safety of a BRAF inhibitor, encorafenib, combined with an MEK inhibitor, binimetinib, in patients with BRAF V600-mutated thyroid cancer. Methods: This phase 2, open-label, uncontrolled study was conducted at 10 institutions targeted patients with BRAF V600-mutated locally advanced or distant metastatic thyroid cancer not amenable to curative treatment who became refractory/intolerant to ≥1 previous vascular endothelial growth factor receptor-targeted regimen(s) or were considered ineligible for those. The primary endpoint was centrally assessed objective response rate (ORR). The secondary endpoints included duration of response (DOR), progression-free survival (PFS), overall survival (OS), and safety. Results: We enrolled 22 patients with BRAFV600E-mutated thyroid cancer: 17 had differentiated thyroid cancer (DTC), and 5 had ATC. At data cutoff (October 26, 2022), the median follow-up was 11.5 (range = 3.4-19.0) months. The primary endpoint of centrally assessed ORR was 54.5% (95% confidence interval [CI] 32.2-75.6; partial response in 12 patients and stable disease in 10). The ORRs in patients with DTC and ATC were 47.1% (8 of 17) and 80.0% (4 of 5), respectively. The medians for DOR and PFS by central assessment and for OS were not reached in the overall population, the DTC subgroup, or the ATC subgroup. At 12 months, the rate of ongoing response was 90.9%, and the PFS and OS rates were 78.8% and 81.8%, respectively. All patients developed ≥1 adverse events (AEs): grade 3 AEs in 6 patients (27.3%). No patients developed grade 4-5 AEs. The most common grade 3 AE was lipase increased (4 patients [18.2%]). Those toxicities were mostly manageable with appropriate monitoring and dose adjustment. Conclusions: Treatment with encorafenib plus binimetinib met the primary endpoint criteria and demonstrated clinical benefit in patients with BRAFV600E-mutated thyroid cancer regardless of its histological type, such as DTC or ATC, with no new safety concerns identified. Encorafenib plus binimetinib could thus be a new treatment option for BRAF V600-mutated thyroid cancer. Clinical Trial Registration number: Japan Registry of Clinical Trials: jRCT2011200018.

Treatment experience with encorafenib plus binimetinib for BRAF V600-mutant metastatic melanoma: management insights for clinical practice

For patients with locally advanced or metastatic melanoma who have BRAF V600 activating mutations, combination therapy with BRAF and MEK inhibitors is now the standard of care. The combination of encorafenib, a highly selective adenosine triphosphate-competitive BRAF inhibitor, plus binimetinib, a potent, selective, allosteric, non-adenosine triphosphate-competitive MEK1/2 inhibitor, was approved by the US Food and Drug Administration for unresectable or metastatic melanoma with BRAF V600E or V600K mutations based on data from the phase III COLUMBUS study (NCT01909453). Clinical data evaluating BRAF and MEK inhibitor combinations in advanced melanoma indicate a specific profile of adverse events that includes serious retinopathy, skin disorders, and cardiovascular toxicities. Here we provide an overview of the rationale for combining BRAF and MEK inhibitors for the treatment of melanoma, long-term safety results from COLUMBUS, and guidance on managing the most common adverse events associated with this combination based on clinical experience. Proactive and appropriate management of adverse events can allow for longer treatment durations and may result in better treatment outcomes.

Ocular involvement in allergic drug reactions

PURPOSE OF REVIEW

Many systemic medications have been observed to cause ocular toxicity. A subset of these reactions is thought to involve immunomodulation or a hypersensitivity reaction. As new medications are developed, ocular adverse effects are becoming increasingly prevalent. Herein we review immune-mediated drug reactions affecting they eye with special attention to the hypersensitivity mechanisms leading to ocular toxicity.

RECENT FINDINGS

Recent work has focused on mechanisms and risk of immune-mediated ocular adverse drug reactions including genetic susceptibility and loss of ocular immune privilege.

SUMMARY

Given the consequences of immune-mediated ocular adverse drug reactions, clinicians must be aware of these to facilitate early recognition and management. The prompt involvement of an ophthalmologist for diagnosis and management is often essential to preserve vision and avoid long-term morbidity.

[Ocular side effects of modern oncological therapy : Immunological checkpoint and MEK/BRAF signal transduction inhibitors]

In recent years, checkpoint inhibitors have revolutionized the treatment of previously untreatable malignant tumors, significantly improving the life expectancy as well as quality of life in many cases. Checkpoint inhibitors comprise a group of drugs with different mechanisms of action. These include immunological checkpoint inhibitors (iCPI) and intracellular signal transduction inhibitors; however, both substance classes can cause inflammatory or toxic ocular side effects. The frequency of intraocular inflammation (uveitis) is reported to be ca. 1-2%, toxic side effects were observed in up to more than 50% of the patients treated with signal transduction inhibitors. In the following article the main mechanisms of these forms of treatment are characterized. Furthermore, this article presents the currently most frequently used therapeutic agents and their typical ophthalmological side effects to increase awareness and to draw attention to these still rare but increasingly more frequent findings.

The Impact of Systemic Medications on Retinal Function

This study will provide a thorough review of systemic (and select intravitreal) medications, along with illicit drugs that are capable of causing various patterns of retinal toxicity. The diagnosis is established by taking a thorough medication and drug history, and then by pattern recognition of the clinical retinal changes and multimodal imaging features. Examples of all of these types of toxicity will be thoroughly reviewed, including agents that cause retinal pigment epithelial disruption (hydroxychloroquine, thioridazine, pentosan polysulfate sodium, dideoxyinosine), retinal vascular occlusion (quinine, oral contraceptives), cystoid macular edema/retinal edema (nicotinic acid, sulfa-containing medications, taxels, glitazones), crystalline deposition (tamoxifen, canthaxanthin, methoxyflurane), uveitis, miscellaneous, and subjective visual symptoms (digoxin, sildenafil). The impact of newer chemotherapeutics and immunotherapeutics (tyrosine kinase inhibitor, mitogen-activated protein kinase kinase, checkpoint, anaplastic lymphoma kinase, extracellular signal-regulated kinase inhibitors, and others), will also be thoroughly reviewed. The mechanism of action will be explored in detail when known. When applicable, preventive measures will be discussed, and treatment will be reviewed. Illicit drugs (cannabinoids, cocaine, heroin, methamphetamine, alkyl nitrite), will also be reviewed in terms of the potential impact on retinal function.

MAPK Pathways in Ocular Pathophysiology: Potential Therapeutic Drugs and Challenges

Mitogen-activated protein kinase (MAPK) pathways represent ubiquitous cellular signal transduction pathways that regulate all aspects of life and are frequently altered in disease. Once activated through phosphorylation, these MAPKs in turn phosphorylate and activate transcription factors present either in the cytoplasm or in the nucleus, leading to the expression of target genes and, as a consequence, they elicit various biological responses. The aim of this work is to provide a comprehensive review focusing on the roles of MAPK signaling pathways in ocular pathophysiology and the potential to influence these for the treatment of eye diseases. We summarize the current knowledge of identified MAPK-targeting compounds in the context of ocular diseases such as macular degeneration, cataract, glaucoma and keratopathy, but also in rare ocular diseases where the cell differentiation, proliferation or migration are defective. Potential therapeutic interventions are also discussed. Additionally, we discuss challenges in overcoming the reported eye toxicity of some MAPK inhibitors.

Ocular adverse events associated with BRAF and MEK inhibitor combination therapy: a pharmacovigilance disproportionality analysis of the FDA adverse event reporting system

BACKGROUND

BRAF and MEK inhibitor combination therapy have significantly improved the outcome of several BRAF-mutation tumors, but it also confers the risk of drug-induced ocular adverse events (oAEs). However, very few studies focused on this risk.

METHODS

The United States Food and Drug Administration Adverse Event Reporting System (FAERS) data from Quarter 1-2011 to Quarter 2-2022 were searched to detect signs of oAEs of three marketed BRAF and MEK inhibitor combination therapies: vemurafenib plus cobimetinib (V + C), dabrafenib plus trametinib (D + T), and encorafenib plus binimetinib (E + B). Disproportionality analyses were performed by calculating the proportional reporting ratio (PRR), χ2 (chi-square), and reporting odds ratios (RORs) with a 95% confidence interval (CI).

RESULTS

A series of oAEs were identified, including 42 preferred terms, which could be classified into 8 aspects. In addition to previously reported oAEs, several unexpected oAE signals were detected. Moreover, differences in oAE profiles were found among three combination therapies (V + C, D + T, and E + B).

CONCLUSIONS

Our findings support an association between several oAEs and BRAF and MEK inhibitor combination therapies, including several new oAEs. In addition, oAEs profiles may vary across the treatment regimens. Further studies are needed to better quantify these oAEs.

Characterization of Serous Retinopathy Associated with Cobimetinib: Integrated Safety Analysis of Four Studies

INTRODUCTION AND OBJECTIVE

Serous retinopathy can be associated with MEK inhibitors, including cobimetinib. We present results of an integrated safety analysis to further characterize ocular functional and structural changes due to serous retinopathy.

METHODS

Four studies evaluating cobimetinib at the approved dose and schedule in combination with other oncology drugs were included. Study CO39721 incorporated standardized ophthalmologic assessments to fully characterize serous retinopathy events over time and was the primary study for analysis. Supporting information was provided by studies GO28141, WO29479, and GO30182.

RESULTS

In total, 655 patients received one or more doses of cobimetinib and comprised the safety-evaluable population. Overall, 117 patients (17.9%) had one or more serous retinopathy events, 24 (3.7%) had two or more events, and four (0.6%) had three or more events. Grade 3 events occurred in < 2.5% of patients. In CO39721, the median time to onset was 15 days (range 7-111); median time to resolution of first occurrence was 26 days (range 6-591 + days). Twelve of 25 patients (48.0%) recovered without a dose modification and 4/25 (16.0%) were recovered/recovering following a dose modification. The most frequent presentation of serous retinopathy was focal subretinal fluid on optical coherence tomography (62.8% of cases); in some instances (25.7% of cases), subretinal fluid was multifocal. There was no loss of visual function or visual acuity at serous retinopathy onset or resolution.

CONCLUSIONS

Results from this integrated safety analysis indicate that cobimetinib-associated serous retinopathy can be managed with or without a dose modification of cobimetinib at the discretion of the treating physician. No visual loss or permanent retinal damage was identified on comprehensive ophthalmologic assessments.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov identifiers: NCT03178851, NCT01689519, NCT02322814, and NCT02788279.

A Case of Bilateral Multifocal Choroiditis Associated with BRAF/MEK Inhibitor Use for Metastatic Cutaneous Melanoma

PURPOSE

To report a case of BRAF/MEK inhibitor-associated multifocal choroiditis that recurred after medication re-exposure and resolved after discontinuing BRAF/MEK inhibition and administering local steroid therapy.

CASE REPORT

A 32-year-old woman with metastatic cutaneous melanoma on dabrafenib/trametinib presented with bilateral anterior uveitis and new bilateral multifocal chorioretinal scars. The anterior uveitis resolved after a course of topical steroids. She presented 18 months later with reactivation of bilateral multifocal choroiditis after starting encorafenib/binimetinib 1 month prior. The chorioretinal lesions appeared elevated with associated vitreous cell. Indocyanine angiography showed numerous foci of new choroiditis, more pronounced in the left eye. Encorafenib/binimetinib was discontinued and a subtenon triamcinolone injection was administered to the left eye. Her symptoms improved and the choroiditis resolved.

CONCLUSION

BRAF/MEK inhibitors may be associated with ocular toxicity manifesting as multifocal choroiditis. The increasing use of these agents and risk of visual impairment warrants early detection and management.

Retinal Toxicity Induced by Chemical Agents

Vision is an important sense for humans, and visual impairment/blindness has a huge impact in daily life. The retina is a nervous tissue that is essential for visual processing since it possesses light sensors (photoreceptors) and performs a pre-processing of visual information. Thus, retinal cell dysfunction or degeneration affects visual ability and several general aspects of the day-to-day of a person's lives. The retina has a blood-retinal barrier, which protects the tissue from a wide range of molecules or microorganisms. However, several agents, coming from systemic pathways, reach the retina and influence its function and survival. Pesticides are still used worldwide for agriculture, contaminating food with substances that could reach the retina. Natural products have also been used for therapeutic purposes and are another group of substances that can get to the retina. Finally, a wide number of medicines administered for different diseases can also affect the retina. The present review aimed to gather recent information about the hazard of these products to the retina, which could be used to encourage the search for more healthy, suitable, or less risky agents.

A clinical case of the development of choroidal neovascularization in a patient with skin melanoma on the background of therapy with MEK and BRAF inhibitors

The emergence of targeted therapy has become a significant breakthrough in the management of cancer patients, but even it is not without drawbacks. The article describes a clinical case of the development choroidal neovascularization in a 42-year-old patient with stage IV skin melanoma during 15 months of therapy with MEK and BRAF inhibitors. Clinicians need to remember that such patients may have not only MEK-associated retinopathy, but also other pathological changes in the retina, in particular choroidal neovascularization, which may be associated with both the chemotherapy they receive and the paraneoplastic syndrome itself against the background of the course of the underlying disease. Timely diagnosis and adequate management tactics allow such patients to preserve visual functions.

Mitogen-activated protein kinase inhibitor-associated retinopathy (MEKAR). A clinical case

Mitogen-activated protein kinase kinase (MEK) inhibitors have significantly improved the prognosis of various types of cancer such as metastatic melanoma. However, their use is usually associated with ocular side effects. A retinopathy associated with these agents (MEKAR) has been described, consisting of the development of neurosensory detachments, generally bilateral and multiple, similar to those that appear in the central serous chorioretinopathy (CSC). Generally, optical coherence tomography allows us to differentiate the two conditions. We present the case of a 55-year-old woman in treatment with a MEK inhibitor, who developed bilateral neurosensory detachments and blurred vision, which resolved with the discontinuance of the treatment due to tumour progression.

Efficacy and Safety of Selumetinib in Pediatric Patients With Neurofibromatosis Type 1: A Systematic Review and Meta-analysis

BACKGROUND AND OBJECTIVES

Although the recent approval of selumetinib is expected to transform the management of children with Neurofibromatosis type 1 (NF1), particularly those with symptomatic and inoperable PN, no systematic review has summarized their efficacy and safety based on the latest studies. This study was conducted to systematically evaluate the efficacy and safety of selumetinib in children with NF1 METHODS: Original articles reporting the efficacy and safety of selumetinib in patients with NF1 were identified in PubMed and EMBASE up to January 28, 2021. The pooled objective response rates (ORRs) and disease control rates (DCRs) were calculated using the DerSimonian-Laird method based on random-effects modeling. The pooled proportion of adverse events (AEs) was also calculated. The quality of the evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluation system.

RESULTS

Five studies involving 126 patients were included in our analysis. The studies had a very low to moderate quality of the evidence. The pooled ORR was 73.8% (95% CI: 57.3-85.5%), and the DCR was 92.5% (95% CI: 66.5-98.7%). The two most common AEs were diarrhea, which had a pooled rate of 63.8% (95% CI, 52.9-73.4%) and an increase in creatine kinase levels, which had a pooled rate of 63.3% (95% CI, 35.6-84.3%).

DISCUSSION

Our results indicate that selumetinib is an effective and safe treatment for pediatric patients with symptomatic, inoperable plexiform neurofibromas. Further larger-scale randomized controlled studies are needed to confirm the long-term outcome of patients treated with this drug.

Update on Retinal Drug Toxicities

Purpose of Review

This review aims to provide an update on the clinical presentations and diagnostic findings of drug-induced retinal toxicities.

Recent Findings

Several newly FDA-approved medications have been associated with acute retinal toxicities, including brolucizumab, MEK inhibitors, ulixertinib, and FGFR inhibitors. Additionally, as previously believed-to-be well-tolerated medications, such as pentosan sulfate sodium, anti-retroviral therapies, and certain intraoperative ocular medications, are used more frequently or for longer periods of time, associated toxic retinopathies and inflammatory reactions have been reported. Finally, advances in ocular imaging have revealed novel findings in hydroxychloroquine and tamoxifen maculopathies.

Summary

Discovery of new medications, increased frequency of use, and longer-term use have led to increased reports of retinal toxicities. Advances in retinal imaging have allowed for earlier detection of subclinical changes associated with these medications, which may help prevent progression of disease. However, more research is needed to determine the point at which vision loss becomes irreversible. Risks and benefits must be assessed prior to discontinuation of the offending, but potentially lifesaving, therapy.

Rapidly Changing Serous Detachment During BRAF and MEK Inhibitor Therapy

We report a case of rapidly changing serous retinal detachment (SRD) during melanoma therapy with a combination of encorafenib, a serine/threonine-protein kinase B-Raf (BRAF) inhibitor, and binimetinib, a mitogen-activated protein kinase (MEK) inhibitor. A 50-year-old woman with metastatic melanoma presented with a sudden visual blur. She had been treated with encorafenib (450 mg every morning) and binimetinib (45 mg every 12 hours) after surgery for four months. Ophthalmological examination revealed bilateral SRD, but it was completely resolved after two hours. Visual acuity was normal in each eye. Encorafenib and binimetinib were continued. Shallow SRD appeared again five months later, but it resolved in two months. MEKAR typically occurs shortly after the start of an administration, and its development after several months was very little known. Continued examination for ophthalmic events should be considered.

Clinical and Morphologic Characteristics of Extracellular Signal-Regulated Kinase Inhibitor-Associated Retinopathy

PURPOSE

To investigate clinical and morphologic characteristics of serous retinal disturbances in patients taking extracellular signal-regulated kinase (ERK) inhibitors.

DESIGN

Single-center retrospective study of prospectively collected data.

PARTICIPANTS

Of 61 patients receiving ERK inhibitors for treatment of metastatic cancer, this study included 40 eyes of 20 patients with evidence of retinopathy confirmed by OCT.

METHODS

Clinical examination, fundus photography, and OCT were used to evaluate ERK inhibitor retinopathy. The morphologic features, distribution, and location of fluid foci were evaluated serially. Visual acuity (VA) and choroidal thickness measurements were compared at baseline, fluid accumulation, and resolution.

MAIN OUTCOME MEASURES

Characteristics of treatment-emergent choroid and retinal OCT abnormalities as compared with baseline OCT findings and the impact of toxicity on VA.

RESULTS

Of 20 patients with retinopathy, most showed fluid foci that were bilateral (100%), multifocal in each eye (75%), and with at least 1 focus involving the fovea (95%). All subretinal fluid foci occurred between the interdigitation zone and an intact retinal pigment epithelium. No statistical difference was found in choroidal thickness at fluid accumulation and resolution compared with baseline. Forty-five percent of eyes showed evidence of concomitant intraretinal edema localized to the outer nuclear layer. At the time of fluid accumulation, 57.5% eyes showed a decline in VA (mainly by 1-2 lines from baseline). For all eyes with follow-up, the subretinal fluid and intraretinal edema were reversible and resolved without medical intervention, and best-corrected VA at fluid resolution was not statistically different from baseline. Concomitant intraretinal fluid was not associated with worsening of VA. No patient discontinued or decreased drug dose because of retinopathy.

CONCLUSIONS

This study showed that ERK inhibitors may cause subretinal fluid foci with unique clinical and morphologic characteristics. The observed foci were similar to mitogen-activated protein kinase kinase (MEK) inhibitor-associated retinopathy and distinct from central serous chorioretinopathy. However, unlike with MEK inhibitors, an increased occurrence of concomitant intraretinal fluid without significant additive visual impact seems to occur with ERK inhibitors. In this series, ERK inhibitors did not cause irreversible loss of vision or serious eye damage; retinopathy was self-limited and did not require medical intervention.

Histiocytic Neoplasms, Version 2.2021, NCCN Clinical Practice Guidelines in Oncology

Histiocytic neoplasms are rare hematologic disorders accounting for less than 1% of cancers of the soft tissue and lymph nodes. Clinical presentation and prognosis of these disorders can be highly variable, leading to challenges for diagnosis and optimal management of these patients. Treatment often consists of systemic therapy, and recent studies support use of targeted therapies for patients with these disorders. Observation ("watch and wait") may be sufficient for select patients with mild disease. These NCCN Guidelines for Histiocytic Neoplasms include recommendations for diagnosis and treatment of adults with the most common histiocytic disorders: Langerhans cell histiocytosis, Erdheim-Chester disease, and Rosai-Dorfman disease.

Retinal toxicities of systemic anticancer drugs

Newer anticancer drugs have revolutionized cancer treatment in the last decade, but conventional chemotherapy still occupies a central position in many cancers, with combination therapy and newer methods of delivery increasing their efficacy while minimizing toxicities. We discuss the retinal toxicities of anticancer drugs with an emphasis on the mechanism of toxicity. Uveitis is seen with the use of v-raf murine sarcoma viral oncogene homolog B editing anticancer inhibitors as well as immunotherapy. Most of the cases are mild with only anterior uveitis, but severe cases of posterior uveitis, panuveitis, and Vogt-Koyanagi-Harada-like disease may also occur. In the retina, a transient neurosensory detachment is observed in almost all patients on mitogen-activated protein kinase kinase (MEK) inhibitors. Microvasculopathy is often seen with interferon α, but vascular occlusion is a more serious toxicity caused by interferon α and MEK inhibitors. Crystalline retinopathy with or without macular edema may occur with tamoxifen; however, even asymptomatic patients may develop cavitatory spaces seen on optical coherence tomography. A unique macular edema with angiographic silence is characteristic of taxanes. Delayed dark adaptation has been observed with fenretinide. Interestingly, this drug is finding potential application in Stargardt disease and age-related macular degeneration.

Ocular Toxicity of Targeted Anticancer Agents

The proliferation of targeted anticancer agents over the last two decades has revolutionized cancer treatment and improved survival in many previously refractory malignancies. However, many agents are associated with characteristic ophthalmic adverse effects. It is important that ophthalmologists recognize and maintain a high index of suspicion for these side effects in patients on targeted therapy. Most ophthalmic adverse effects can be treated with specific ocular therapy without discontinuation of cancer treatment, although it is important to be aware of the life-threatening and vision-threatening circumstances that would require therapy cessation in conjunction with the patient's oncologist. This review aims to summarize the ophthalmic adverse effects of targeted and hormonal anticancer agents and briefly describe their management.

[Management of toxicities of BRAF inhibitors and MEK inhibitors in advanced melanoma]

Major therapeutic advances have been made recently in the treatment of metastatic melanoma, due to the development of targeted therapies, namely BRAF and MEK inhibitors, in patients with BRAF V600 mutation. Combinations of vemurafenib+cobimetinib, dabrafenib+trametinib, et encorafenib+binimetinib, evaluated in coBRIM, COMBI-d/COMBI-v and COLUMBUS trials respectively have been approved in this indication. Toxicities induced by combination therapies are different from those reported with monotherapies, in terms of frequency and intensity. Physicians who treat melanoma patients thus face news issues relating to prevention, detection and treatment of these adverse events. This paper summarizes tolerance data from the three pivotal trials (coBRIM, COMBI-v and COLUMBUS) and issues recommendations for the specific management of main toxicities, based on experts' opinion. We discuss dermatological, ophthalmological, cardiovascular, digestive, musculoskeletal, renal and general toxicities and propose a timetable for examinations to be performed before and during treatment.

The association between immune checkpoint or BRAF/MEK inhibitor therapy and uveitis in patients with advanced cutaneous melanoma

BACKGROUND

Treatment with immune checkpoint and BRAF/MEK inhibitors has significantly improved the survival of patients with advanced cutaneous melanoma and other metastatic malignancies. Therapy-related uveitis is a rare ocular adverse event, which may potentially lead to legal blindness. The epidemiology of treatment-related uveitis is currently insufficiently known.

PATIENTS AND METHODS

In this cohort study, we asked whether exposure to either immune checkpoint or BRAF/MEK inhibitors was associated with a higher risk of developing uveitis compared with the general population. Based on a Bayesian framework, we estimated the probability of developing uveitis with a right-censored, exponential survival model using data from the Zurich Melanoma Registry. The registry included all adult patients treated for advanced cutaneous melanoma between January 2008 and December 2018 at the University Hospital of Zurich, Switzerland.

RESULTS

In total, 304 patients (64%) were treated with immune checkpoint and 186 patients (38%) with BRAF/MEK inhibitors. Median follow-up time was 74 days (interquartile range: 57-233 days). Eleven patients developed uveitis and 30 patients died. We estimated the probability of developing uveitis per year in the general population as 0.05% (95% credibility interval [CrI]: 0.02%-0.1%). Corresponding posterior probabilities of treatment-related uveitis were 3.48% (95% CrI: 0.93%-7.49%) and 5.04% (95% CrI: 2.07%-9.19%) for immune checkpoint or BRAF/MEK inhibitors (posterior probability for difference: 76%).

CONCLUSIONS

Immune checkpoint and particularly BRAF/MEK inhibitor therapies are associated with an increase in the risk of developing uveitis. Treatment-related uveitis is not associated with systemic adverse events of immune checkpoint or BRAF/MEK inhibitors.

Intermittent schedules of the oral RAF-MEK inhibitor CH5126766/VS-6766 in patients with RAS/RAF-mutant solid tumours and multiple myeloma: a single-centre, open-label, phase 1 dose-escalation and basket dose-expansion study

BACKGROUND

CH5126766 (also known as VS-6766, and previously named RO5126766), a novel MEK-pan-RAF inhibitor, has shown antitumour activity across various solid tumours; however, its initial development was limited by toxicity. We aimed to investigate the safety and toxicity profile of intermittent dosing schedules of CH5126766, and the antitumour activity of this drug in patients with solid tumours and multiple myeloma harbouring RAS-RAF-MEK pathway mutations.

METHODS

We did a single-centre, open-label, phase 1 dose-escalation and basket dose-expansion study at the Royal Marsden National Health Service Foundation Trust (London, UK). Patients were eligible for the study if they were aged 18 years or older, had cancers that were refractory to conventional treatment or for which no conventional therapy existed, and if they had a WHO performance status score of 0 or 1. For the dose-escalation phase, eligible patients had histologically or cytologically confirmed advanced or metastatic solid tumours. For the basket dose-expansion phase, eligible patients had advanced or metastatic solid tumours or multiple myeloma harbouring RAS-RAF-MEK pathway mutations. During the dose-escalation phase, we evaluated three intermittent oral schedules (28-day cycles) in patients with solid tumours: (1) 4·0 mg or 3·2 mg CH5126766 three times per week; (2) 4·0 mg CH5126766 twice per week; and (3) toxicity-guided dose interruption schedule, in which treatment at the recommended phase 2 dose (4·0 mg CH5126766 twice per week) was de-escalated to 3 weeks on followed by 1 week off if patients had prespecified toxic effects (grade 2 or worse diarrhoea, rash, or creatinine phosphokinase elevation). In the basket dose-expansion phase, we evaluated antitumour activity at the recommended phase 2 dose, determined from the dose-escalation phase, in biomarker-selected patients. The primary endpoints were the recommended phase 2 dose at which no more than one out of six patients had a treatment-related dose-limiting toxicity, and the safety and toxicity profile of each dosing schedule. The key secondary endpoint was investigator-assessed response rate in the dose-expansion phase. Patients who received at least one dose of the study drug were evaluable for safety and patients who received one cycle of the study drug and underwent baseline disease assessment were evaluable for response. This trial is registered with ClinicalTrials.gov, NCT02407509.

FINDINGS

Between June 5, 2013, and Jan 10, 2019, 58 eligible patients were enrolled to the study: 29 patients with solid tumours were included in the dose-escalation cohort and 29 patients with solid tumours or multiple myeloma were included in the basket dose-expansion cohort (12 non-small-cell lung cancer, five gynaecological malignancy, four colorectal cancer, one melanoma, and seven multiple myeloma). Median follow-up at the time of data cutoff was 2·3 months (IQR 1·6-3·5). Dose-limiting toxicities included grade 3 bilateral retinal pigment epithelial detachment in one patient who received 4·0 mg CH5126766 three times per week, and grade 3 rash (in two patients) and grade 3 creatinine phosphokinase elevation (in one patient) in those who received 3·2 mg CH5126766 three times per week. 4·0 mg CH5126766 twice per week (on Monday and Thursday or Tuesday and Friday) was established as the recommended phase 2 dose. The most common grade 3-4 treatment-related adverse events were rash (11 [19%] patients), creatinine phosphokinase elevation (six [11%]), hypoalbuminaemia (six [11%]), and fatigue (four [7%]). Five (9%) patients had serious treatment-related adverse events. There were no treatment-related deaths. Eight (14%) of 57 patients died during the trial due to disease progression. Seven (27% [95% CI 11·6-47·8]) of 26 response-evaluable patients in the basket expansion achieved objective responses.

INTERPRETATION

To our knowledge, this is the first study to show that highly intermittent schedules of a RAF-MEK inhibitor has antitumour activity across various cancers with RAF-RAS-MEK pathway mutations, and that this inhibitor is tolerable. CH5126766 used as a monotherapy and in combination regimens warrants further evaluation.

FUNDING

Chugai Pharmaceutical.

OCULAR ADVERSE EVENTS ASSOCIATED WITH MEK INHIBITORS

PURPOSE

Mitogen-activates protein kinase (MAPK) inhibitors, particularly MEK inhibitors, have shifted the treatment paradigm for metastatic BRAF-mutant cutaneous melanoma; however, oncologists, ophthalmologists, and patients have noticed different toxicities of variable importance. This review aims to provide an update of the ocular adverse events (OAEs), especially retinal toxicity, associated with the use of MEK inhibitors.

METHODS

We conducted a scientific literature search using the PubMed database up to July 2018 with the terms "MEK inhibitors" with a "review" filter and "MEK inhibitors" with a "clinical trials" filter. Phase I-III experimental studies and reviews were selected. Current principles and techniques for diagnosing and managing MEK inhibitor retinopathy and other OAEs are discussed.

RESULTS

In patients treated with MEK inhibitors, including asymptomatic patients, OAEs occur with an incidence of up to 90%. Mild to severe ophthalmic toxicities are described, including visual disturbances, a 2-line decrease in Snellen visual acuity, dry eye symptoms, ocular adnexal abnormalities, visual field defects, panuveitis, and retinal toxicities, such as different degrees of MEK-associated retinopathy, vascular injury, and retinal vein occlusion.

CONCLUSION

MEK inhibitors can lead to different degrees of retinal, uveal, and adnexal OAE, causing visual disturbances or discomfort. One of the most relevant OAE of MEK therapy is MEK inhibitor-associated retinopathy (MEKAR), which is usually mild, self-limited, and may subside after continuous use of the drug for weeks or months, or discontinuation, thereby restoring the normal visual function of the retina, with some exceptions. Ocular adverse events are often associated with other systemic adverse effects that can modify the dosage of treatment, so the communication with the oncologist is fundamental.

Encorafenib, binimetinib and cetuximab combined therapy for patients with BRAFV600E mutant metastatic colorectal cancer

Approximately 10-15% of colorectal cancers (CRCs) harbor an activating BRAF mutation, leading to tumor growth promotion by activation of the mitogen-activated protein kinases pathway. BRAFV600E mutations are prognostic for treatment failure after first-line systemic therapy in the metastatic setting. In contrast to the efficacy of combined BRAF and MEK inhibition in melanoma, BRAFV600E mutant CRC is intrinsically unresponsive due to upregulation of HER/EGFR. However, combining the EGFR inhibitor cetuximab, the BRAF inhibitor encorafenib and the MEK inhibitor binimetinib improves overall survival. This review discusses the current treatment field for patients with BRAFV600E mutant metastatic CRC and summarizes the pharmacology, efficacy and safety of the novel doublet and triplet therapies consisting of encorafenib and cetuximab with or without binimetinib.

A novel side effect of mitogen-activated protein kinase inhibitor cobimetinib: Acute corneal decompensation

A 38-year-old man with a diagnosis of BRAF-mutated metastatic melanoma was referred to our clinic. He had been under treatment with 60-mg oral cobimetinib daily for 21 days/7 day off in combination with 960 mg vemurafenib twice daily. The patient had symptoms of blurred vision and photophobia in his right eye. A slit-lamp examination revealed bilateral central corneal stromal opacity and epithelial microcystic edema Involvement was more severe in the right eye compared with the left eye. Fourteen days after the first visit, the patient's symptoms and slit-lamp findings were largely resolved. We suggest that endothelium pump failure was involved in this acute corneal decompensation case similar to the mechanism in retinal pigment epithelium.

Risk factors for MEK-associated retinopathy in patients with advanced melanoma treated with combination BRAF and MEK inhibitor therapy

BACKGROUND

Retinopathy is a common adverse event with mitogen-activated extracellular signal-regulated kinase (MEK) inhibitors. Little is known about the pathophysiology of MEK inhibitor-associated retinopathy (MEKAR). Since MEKAR has many similarities to central serous chorioretinopathy (CSCR), they may share common risk factors. The aim of this study was to evaluate the association between baseline characteristics and MEKAR in melanoma patients initiating MEK inhibitor treatment.

METHODS

Data from patients treated with cobimetinib and vemurafenib for advanced melanoma in the coBRIM trial were subjected to secondary analysis. Consistent with CSCR risk factors, assessed baseline characteristics included: age, gender, past ocular disease, weight, hypertension, diabetes, dyslipidemia, glomerular filtration rate (eGFR) and corticosteroid use. Associations between characteristics and retinopathy events (any grade and symptomatic) were evaluated using univariate logistic regression and represented as odds ratios (OR).

RESULTS

A total of 247 patients were treated with cobimetinib and vemurafenib, of whom 72 (29%) had retinopathy of any grade and 33 (13%) had symptomatic retinopathy. Patients with a history of ocular disease were at significantly higher risk of retinopathy (any grade, 44%; symptomatic, 22%) than those with no ocular disease history (any grade, 22%; symptomatic, 10%). Individuals with a history of ocular inflammation or infection were at highest risk: 4 of 5 developed symptomatic retinopathy during MEK inhibitor therapy. Increased age was associated with a higher risk of any grade retinopathy {decade increase OR [95% confidence interval (CI)] = 1.03 (1.01-1.05); p = 0.009}, while increasing eGFR was significantly associated with a decreased risk of any grade retinopathy [0.98 (0.96-0.99); p = 0.004]; the associations were not statistically significant with symptomatic retinopathy. Other assessed CSCR risk factors were not significantly associated with MEKAR.

CONCLUSION

Age, glomerular filtration rate and history of ocular disease (particularly inflammatory eye disease) were associated with a risk of MEK inhibitor induced retinopathy. Patients who are at increased risk of MEKAR may benefit from more regular ophthalmologic assessment during treatment.

The Use of MEK Inhibitors in Neurofibromatosis Type 1-Associated Tumors and Management of Toxicities

Early-phase clinical trials using oral inhibitors of MEK, the mitogen-activated protein kinase kinase, have demonstrated benefit for patients with neurofibromatosis type 1 (NF1)-associated tumors, particularly progressive low-grade gliomas and plexiform neurofibromas. Given this potential of MEK inhibition as an effective medical therapy, the use of targeted agents in the NF1 population is likely to increase substantially. For clinicians with limited experience prescribing MEK inhibitors, concern about managing these treatments may be a barrier to use. In this manuscript, the Clinical Care Advisory Board of the Children's Tumor Foundation reviews the published experience with MEK inhibitors in NF1 and outlines recommendations for side-effect management, as well as monitoring guidelines. These recommendations can serve as a beginning framework for NF providers seeking to provide the most effective treatments for their patients. IMPLICATIONS FOR PRACTICE: Neurofibromatosis type 1 (NF1) clinical care is on the cusp of a transformative shift. With the success of recent clinical trials using MEK inhibitors, an increasing number of NF1 patients are being treated with MEK inhibitors for both plexiform neurofibromas and low-grade gliomas. The use of MEK inhibitors is likely to increase substantially in NF1. Given these changes, the Clinical Care Advisory Board of the Children's Tumor Foundation has identified a need within the NF1 clinical community for guidance for the safe and effective use of MEK inhibitors for NF1-related tumors. This article provides a review of the published experience of MEK inhibitors in NF1 and provides recommendations for monitoring and management of side effects.

Factors associated with ocular adverse event after immune checkpoint inhibitor treatment

Ocular adverse events (OAEs) including vision-threatening intraocular inflammation after immune checkpoint inhibitor (ICI) treatment have been increasingly reported; however, the risk factors associated with OAEs remain elusive. Here, we determined the factors associated with OAEs after ICI treatment. We analyzed 40 consecutive patients who experienced OAEs after ICI treatments. The OAEs included anterior uveitis, chorioretinitis, papillitis, foveal interdigitation zone thickening/serous retinal detachment (IZT/SRD), retinal vascular occlusion, and strabismus and ptosis. Of 40 patients, 18 (45%) were treated with atezolizumab, 13 (33%) with pembrolizumab, 7 (18%) with nivolumab, 1 (3%) with ipilimumab/nivolumab, and the other 1 (3%) with durvalumab/tremelimumab. BRAF/MEK inhibitors were concurrently used in 19 (48%) patients. Occurrence of intraocular inflammation was significantly associated with previous ocular surgery and trauma history (P = 0.015) and pembrolizumab use (P = 0.031). Neuro-ophthalmic complications and IZT/SRD were associated with brain metastasis (P = 0.005) and treatment with BRAF/MEK inhibitor (P < 0.001), respectively. In extensive literature review for clinical cases, we identified seven cases with intraocular inflammation, which were not observed with ipilimumab treatment, that occurred after a change of the drug to pembrolizumab. Collectively, these findings provide better understandings of OAEs after ICI treatment.

Left ventricular ejection fraction decrease related to BRAF and/or MEK inhibitors in metastatic melanoma patients: A retrospective analysis

BRAF and MEKis have revolutionized the management of BRAF^V600‐mutated melanoma patients. Left ventricular ejection fraction decrease (LVEF‐D) related to these treatments has not been thoroughly evaluated to date. The main objective of this study was to describe characteristics of LVEF‐D in melanoma patients treated with BRAF and/or MEKis. Metastatic melanoma patients treated with BRAF and/or MEKis between March 1, 2012 and May 18, 2018 were included retrospectively (Lyon Sud University Hospital, Hospices Civils de Lyon). LVEF‐D was defined as a reduction in LVEF ≥10% from baseline to a value <55%; normalization was defined as a value ≥55%. Among the 88 patients included, 12 (13.6%) experienced a LVEF‐D, including 10 grade 2 and 2 grade 3. The median onset of which was 11 months (IQR [3‐21]). No patient previously treated with beta‐blockers (n = 12) experienced a LVEF‐D. Analysis of laboratory parameters, electrocardiogram, and transthoracic echocardiography during the follow‐up did not find any predictive marker of LVEF‐D. All patients who benefited from a specific treatment of LVEF‐D had a normalization of LVEF at the end of follow‐up. LVEF recovery was significantly better for patients treated with angiotensin converting enzyme inhibitors and beta‐blockers than those who did not (P = .019). Ophthalmological adverse events were significantly more frequent in patients who experienced a LVEF‐D (P = .006) and the latter did not influence overall‐survival (P = .117) or progression‐free‐survival (P = .297). LVEF‐D is a common and easily manageable adverse event due to BRAF and MEKis. Its association with ocular toxicity suggests a close ophthalmological monitoring when LVEF‐D occurs.

Wide field retinal imaging and the detection of drug associated retinal toxicity

Background

To describe the peripheral retinal findings associated with systemic medication toxicity and to outline the importance of ultra-widefield imaging in the detection, analysis and monitoring of these abnormalities.

Main text

This review highlights the retinal manifestations associated with the more common drug toxicities, with emphasis on the peripheral features and the indications for wide field imaging. The presenting findings, underlying pathophysiology, and retinal alterations in hydroxychloroquine, thioridazine, didanosine, tamoxifen, MEK-inhibitor, and immune checkpoint inhibitor associated drug toxicity will be described and the importance of wide field imaging in the evaluation of these abnormalities will be emphasized.

Conclusions

Wide field retinal imaging can improve the detection of peripheral retinal abnormalities associated with drug toxicity and may be an important tool in the diagnosis and management of these disorders.

Adverse events associated with encorafenib plus binimetinib in the COLUMBUS study: incidence, course and management

BACKGROUND

Dual inhibition of the mitogen-activated protein kinase pathway with BRAF/MEK inhibitor (BRAFi/MEKi) therapy is a standard treatment for BRAFV600-mutant metastatic melanoma and has historically been associated with grade III pyrexia or photosensitivity depending on the combination used. The objective of this study was to fully describe adverse events from the COLUMBUS study evaluating the most recent BRAF/MEK inhibitor combination encorafenib+binimetinib.

PATIENTS AND METHODS

Patients with locally advanced, unresectable or metastatic BRAFV600-mutant melanoma were randomised to receive encorafenib 450 mg once daily plus binimetinib 45 mg twice daily, encorafenib 300 mg once daily or vemurafenib 960 mg twice daily. Adverse events that represent known effects of available BRAFi and/or MEKi were evaluated.

RESULTS

The safety population included a total of 570 patients (encorafenib+binimetinib = 192; encorafenib = 192; vemurafenib = 186). Median duration of exposure was longer with encorafenib+binimetinib (51 weeks) than with encorafenib (31 weeks) or vemurafenib (27 weeks). Common BRAFi/MEKi toxicities with encorafenib+binimetinib were generally manageable, reversible and infrequently associated with discontinuation. Pyrexia was less frequent with encorafenib+binimetinib (18%) and encorafenib (16%) than with vemurafenib (30%) and occurred later in the course of therapy with encorafenib+binimetinib (median time to first onset: 85 days versus 2.5 days and 19 days, respectively). The incidence of photosensitivity was lower with encorafenib+binimetinib (5%) and encorafenib (4%) than with vemurafenib (30%). The incidence of serous retinopathy was higher with encorafenib+binimetinib (20%) than with encorafenib (2%) or vemurafenib (2%), but no patients discontinued encorafenib+binimetinib because of this event.

CONCLUSION

Encorafenib+binimetinib is generally well tolerated and has a low discontinuation rate in patients with BRAFV600-mutant melanoma, with a distinct safety profile as compared with other anti-BRAF/MEK targeted therapies.

TRIAL REGISTRATION

ClinicalTrials.gov (Identifier: NCT01909453) and with EudraCT (number 2013-001176-38).

Binimetinib, Encorafenib, and Cetuximab Triplet Therapy for Patients With BRAF V600E-Mutant Metastatic Colorectal Cancer: Safety Lead-In Results From the Phase III BEACON Colorectal Cancer Study

PURPOSE

To determine the safety and preliminary efficacy of selective combination targeted therapy for BRAF V600E-mutant metastatic colorectal cancer (mCRC) in the safety lead-in phase of the open-label, randomized, three-arm, phase III BEACON Colorectal Cancer trial ( ClinicalTrials.gov identifier: NCT02928224; European Union Clinical Trials Register identifier: EudraCT2015-005805-35).

PATIENTS AND METHODS

Before initiation of the randomized portion of the BEACON Colorectal Cancer trial, 30 patients with BRAF V600E-mutant mCRC who had experienced treatment failure with one or two prior regimens were to be recruited to a safety lead-in of encorafenib 300 mg daily, binimetinib 45 mg twice daily, plus standard weekly cetuximab. The primary end point was safety, including the incidence of dose-limiting toxicities. Efficacy end points included overall response rate, progression-free survival, and overall survival.

RESULTS

Among the 30 treated patients, dose-limiting toxicities occurred in five patients and included serous retinopathy (n = 2), reversible decreased left ventricular ejection fraction (n = 1), and cetuximab-related infusion reactions (n = 2). The most common grade 3 or 4 adverse events were fatigue (13%), anemia (10%), increased creatine phosphokinase (10%), increased AST (10%), and urinary tract infections (10%). In 29 patients with BRAF V600E-mutant tumors (one patient had a non-BRAF V600E-mutant tumor and was not included in the efficacy analysis), the confirmed overall response rate was 48% (95% CI, 29.4% to 67.5%), median progression-free survival was 8.0 months (95% CI, 5.6 to 9.3 months), and median overall survival was 15.3 months (95% CI, 9.6 months to not reached), with median duration of follow-up of 18.2 months (range, 16.6 to 19.8 months).

CONCLUSION

In the safety lead-in, the safety and tolerability of the encorafenib, binimetinib, and cetuximab regimen is manageable and acceptable for initiation of the randomized portion of the study. The observed efficacy is promising compared with available therapies and, if confirmed in the randomized portion of the trial, could establish this regimen as a new standard of care for previously treated BRAF V600E-mutant mCRC.

Tolerability of BRAF/MEK inhibitor combinations: adverse event evaluation and management

The inhibition of the mitogen-activated protein kinases signalling pathway through combined use of BRAF and MEK inhibitors (BRAFi+MEKi) represents an established therapeutic option in patients with BRAF-mutated, advanced melanoma. These efficient therapies are well tolerated with mostly moderate and reversible side effects and a discontinuation rate due to adverse events of 11.5%-15.7%. Median duration of therapy ranges between 8.8 and 11.7 months. Based on data from confirmatory trials, safety profiles of three BRAFi+MEKi combinations were reviewed, that is, dabrafenib plus trametinib, vemurafenib plus cobimetinib and encorafenib plus binimetinib. Many adverse events are class effects, such as cutaneous, gastrointestinal, ocular, cardiac and musculoskeletal events; some adverse events are substance associated. Fever (dabrafenib) and photosensitivity (vemurafenib) are the most common and clinically prominent examples. Other adverse events are less frequent and the association to one substance is less strong such as anaemia, facial paresis (encorafenib), neutropenia (dabrafenib), skin rash, QTc prolongation and increased liver function tests (vemurafenib). This narrative review provides recommendations for monitoring, adverse event evaluation and management focusing on the clinically relevant side effects of the three regimens.