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.

Effect of Itraconazole, a Potent CYP3A4 Inhibitor, on the Steady-State Pharmacokinetics of Vemurafenib in Patients With BRAFV600 Mutation-Positive Malignancies.

The effects of itraconazole, a strong CYP3A4 inhibitor, on the steady-state pharmacokinetics of vemurafenib were evaluated in a phase 1, multicenter, open-label, fixed-sequence study. Patients with BRAFV600 mutation-positive metastatic malignancies received oral vemurafenib 960 mg twice daily on days 1 to 20 (period A) and oral vemurafenib 960 mg twice daily with oral itraconazole 200 mg once daily on days 21 to 40 (period B). A mixed-effects analysis of variance model was used to compare log-transformed area under the concentration-time curve during the dosing interval and maximum plasma concentration values for vemurafenib in 8 patients between period B (vemurafenib plus itraconazole) and period A (vemurafenib alone). Multiple doses of itraconazole increased steady-state exposure of vemurafenib by approximately 40%, with geometric least squares mean ratios (period B/period A) of 140% (90% confidence interval, 121-161) for both maximum plasma concentration and area under the concentration-time curve during the dosing interval. There was no apparent increase in incidence or severity of adverse events during coadministration of vemurafenib with itraconazole. In conclusion, coadministration of itraconazole with vemurafenib resulted in a modest increase in exposure of vemurafenib at steady state and was generally well tolerated.

Health-related quality of life in patients with fully resected BRAFV600 mutation-positive melanoma receiving adjuvant vemurafenib.

AIM OF STUDY: The aim of the study was to assess the impact of treatment with adjuvant vemurafenib monotherapy on health-related quality of life (HRQOL) in patients with resected stage IIC-IIIC melanoma. METHODS: The phase 3 BRIM8 study (NCT01667419) randomised patients with BRAFV600 mutation-positive resected stage IIC-IIIC melanoma to 960 mg of vemurafenib twice daily or matching placebo for 52 weeks (13 × 28-day cycles). Patients completed the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30) version 3 at baseline, cycle 1 (days 1, 15 and 22), cycle 2 (days 1 and 15), day 1 of every subsequent 4-week cycle, the end-of-treatment visit and each visit during the follow-up period. RESULTS: Completion rates for the EORTC QLQ-C30 questionnaire were high (>80%). There was a mean decline in the global health status (GHS)/quality of life (QOL) score of 17.4 (±22.9) and 17.3 (±24.1) points at days 15 and 22 of cycle 1, respectively, among vemurafenib-treated patients who recovered to approximately 10 points below baseline for the remainder of the treatment period. A similar trend was observed in all functional scales except for cognitive function (<10-point change from baseline at all visits) and in the symptom scores for appetite loss, fatigue and pain. As observed for the GHS/QOL score, all scores rapidly returned to baseline after completion of planned vemurafenib treatment or treatment discontinuation. CONCLUSIONS: The schedule of HRQOL assessments allowed for an accurate and complete evaluation of the impact of acute treatment-related symptoms. Vemurafenib-treated patients experience clinically meaningful moderate worsening in some treatment- or disease-related symptoms and GHS/QOL that resolve over time.

Adjuvant vemurafenib in resected, BRAFV600 mutation-positive melanoma (BRIM8): a randomised, double-blind, placebo-controlled, multicentre, phase 3 trial.

BACKGROUND: Systemic adjuvant treatment might mitigate the high risk of disease recurrence in patients with resected stage IIC-III melanoma. The BRIM8 study evaluated adjuvant vemurafenib monotherapy in patients with resected, BRAFV600 mutation-positive melanoma. METHODS: BRIM8 was a phase 3, international, double-blind, randomised, placebo-controlled study that enrolled 498 adults (aged ≥18 years) with histologically confirmed stage IIC-IIIA-IIIB (cohort 1) or stage IIIC (cohort 2) BRAFV600 mutation-positive melanoma that was fully resected. Patients were randomly assigned (1:1) by an interactive voice or web response system to receive twice-daily adjuvant oral vemurafenib 960 mg tablets or matching placebo for 52 weeks (13 × 28-day cycles). Randomisation was done by permuted blocks (block size 6) and was stratified by pathological stage and region in cohort 1 and by region in cohort 2. The investigators, patients, and sponsor were masked to treatment assignment. The primary endpoint was disease-free survival in the intention-to-treat population, evaluated separately in each cohort. Hierarchical analysis of cohort 2 before cohort 1 was prespecified. This trial is registered with ClinicalTrials.gov, number NCT01667419. FINDINGS: The study enrolled 184 patients in cohort 2 (93 were assigned to vemurafenib and 91 to placebo) and 314 patients in cohort 1 (157 were assigned to vemurafenib and 157 to placebo). At the time of data cutoff (April 17, 2017), median study follow-up was 33·5 months (IQR 25·9-41·6) in cohort 2 and 30·8 months (25·5-40·7) in cohort 1. In cohort 2 (patients with stage IIIC disease), median disease-free survival was 23·1 months (95% CI 18·6-26·5) in the vemurafenib group versus 15·4 months (11·1-35·9) in the placebo group (hazard ratio [HR] 0·80, 95% CI 0·54-1·18; log-rank p=0·26). In cohort 1 (patients with stage IIC-IIIA-IIIB disease) median disease-free survival was not reached (95% CI not estimable) in the vemurafenib group versus 36·9 months (21·4-not estimable) in the placebo group (HR 0·54 [95% CI 0·37-0·78]; log-rank p=0·0010); however, the result was not significant because of the prespecified hierarchical prerequisite for the primary disease-free survival analysis of cohort 2 to show a significant disease-free survival benefit. Grade 3-4 adverse events occurred in 141 (57%) of 247 patients in the vemurafenib group and 37 (15%) of 247 patients in the placebo group. The most common grade 3-4 adverse events in the vemurafenib group were keratoacanthoma (24 [10%] of 247 patients), arthralgia (17 [7%]), squamous cell carcinoma (17 [7%]), rash (14 [6%]), and elevated alanine aminotransferase (14 [6%]), although all keratoacanthoma events and most squamous cell carcinoma events were by default graded as grade 3. In the placebo group, grade 3-4 adverse events did not exceed 2% for any of the reported terms. Serious adverse events were reported in 40 (16%) of 247 patients in the vemurafenib group and 25 (10%) of 247 patients in the placebo group. The most common serious adverse event was basal cell carcinoma, which was reported in eight (3%) patients in each group. One patient in the vemurafenib group of cohort 2 died 2 months after admission to hospital for grade 3 hypertension; however, this death was not considered to be related to the study drug. INTERPRETATION: The primary endpoint of disease-free survival was not met in cohort 2, and therefore the analysis of cohort 1 showing a numerical benefit in disease-free survival with vemurafenib versus placebo in patients with resected stage IIC-IIIA-IIIB BRAFV600 mutation-positive melanoma must be considered exploratory only. 1 year of adjuvant vemurafenib was well tolerated, but might not be an optimal treatment regimen in this patient population. FUNDING: F Hoffman-La Roche Ltd.

Multiple Gastrointestinal Polyps in Patients Treated with BRAF Inhibitors.

PURPOSE: BRAF inhibitors (BRAFi) extend survival in BRAF-mutant melanoma but can promote the growth of Ras-mutant neoplasms. This study determined if gastrointestinal polyps found in BRAFi-treated patients harbored Ras mutations. EXPERIMENTAL DESIGN: Colonic and gastric polyps were identified and resected from BRAFi-treated melanoma patients. Next-generation sequencing (NGS) was performed on polyps. The ability of BRAFi to promote polyp formation was functionally characterized in Apc Min(+/-) mice. MAPK and ß-catenin pathway activity was assessed by immunohistochemistry in mouse and human polyps. RESULTS: Fourteen patients treated with BRAFi underwent endoscopy to assess for polyps. Seven out of 7 patients >40 years of age and treated for >2 years were found to have colonic tubular adenomas with 4 out of the 7 patients having 5 or more polyps. One patient presented with bleeding from hyperplastic gastric polyps that recurred 6 months after BRAFi rechallenge. NGS performed on polyps found no mutations in MAPK pathway genes, but found APC mutations in all tubular adenomas. A significant increase in the number of polyps was observed in BRAFi-treated compared with control-treated Apc Min(+/-) mice (20.8 ± 9.2 vs 12.8 ± 0.1; P = 0.016). No polyps were observed in BRAFi-treated wild-type mice. CONCLUSIONS: BRAFi may increase the risk of developing hyperplastic gastric polyps and colonic adenomatous polyps. Due to the risk of gastrointestinal bleeding and the possibility of malignant transformation, further studies are needed to determine whether or not endoscopic surveillance should be recommended for patients treated with BRAFi.

Hairy cell leukemia: an update.

Hairy cell leukemia is an indolent, chronic B-cell lymphoproliferative disorder comprising approximately 2 to 3% of all adult leukemias in the United States. Hairy cells are clonal expansions of mature, activated B-cells. They co-express CD11c, CD19, CD20, CD22, CD25, and CD103. Hairy cells possess clonal immunoglobulin gene rearrangements and express monoclonal surface immunoglobulin of either IgG or multiple heavy-chain isotypes. Treatment of hairy cell leukemia should be considered for symptomatic patients. It is indicated in patients with significant neutropenia, anemia, thrombocytopenia, symptomatic splenomegaly, constitutional symptoms due to hairy cell leukemia, or recurrent serious infections. Many treatments exist, including cladribine, pentostatin, interferon-alpha, splenectomy, rituximab (mabthera), and BL-22 immunotoxin.

Cladribine in the treatment of hairy-cell leukaemia.

Cladribine, a purine nucleoside analogue, is a safe and effective treatment for patients with hairy-cell leukaemia. It is administered at a dose of 0.09 mg/kg daily as a continuous intravenous infusion over 7 days. This chapter discusses the history, rationale, chemical structure and mechanism of action of cladribine. The indications for therapy and guidelines for clinical usage are reviewed. The response of hairy-cell leukaemia to cladribine, the acute and chronic complications and the risk for second malignancies are summarized. The chapter concludes with a section on salvage therapy.

Extended follow-up of patients with hairy cell leukemia after treatment with cladribine.

PURPOSE: Hairy cell leukemia (HCL) is an uncommon, indolent, chronic B-cell lymphoproliferative disorder involving the marrow and spleen. Therapy for HCL includes splenectomy, interferon alfa-2a and alfa-2b, pentostatin, and cladribine. The purpose of this article was to report the extended follow-up of HCL patients treated with cladribine. PATIENTS AND METHODS: Two hundred nine patients with HCL who were treated with cladribine had at least 7 years of follow-up. A course of cladribine constituted a 7-day continuous intravenous infusion at a dose of 0.1 mg/kg/d. RESULTS: Of the 207 assessable patients who had at least 7 years of follow-up, 196 (95%) achieved a complete response (CR) and 11 (5%) achieved a partial response (PR) after a single course of cladribine (overall response rate, 100%). The median first-response duration for all responders was 98 months. Seventy-six patients (37%) experienced relapse after their first course of cladribine. The median time to first relapse for all responders was 42 months. Time to treatment failure of CRs compared with PRs was statistically significant (P <.0005). The overall survival rate was 97% recorded at 108 months. Forty-seven patients developed 58 second malignancies. The observed-to-expected ratio for second malignancies was 2.03 (95% confidence interval, 1.49 to 2.71). CONCLUSION: These results confirm previous observations that single courses of cladribine administered to patients with HCL induce high response rates, the majority of which are CRs. Most patients enjoy long-lasting complete remissions, and those patients who experience relapse can be successfully re-treated with cladribine.