Pembrolizumab versus placebo as adjuvant therapy in resected stage IIB or IIC melanoma (KEYNOTE-716): distant metastasis-free survival results of a multicentre, double-blind, randomised, phase 3 trial

BACKGROUND

Patients with stage IIB or IIC melanoma who undergo surgery alone are at a substantial risk for disease recurrence. Adjuvant pembrolizumab significantly improved recurrence-free survival versus placebo in stage IIB or IIC melanoma in the first interim analysis of the KEYNOTE-716 trial. Here, we report results from the secondary endpoint of distant metastasis-free survival (prespecified third interim analysis), and recurrence-free survival with longer follow-up.

METHODS

KEYNOTE-716 is a multicentre, double-blind, placebo-controlled, crossover or rechallenge, randomised, phase 3 trial done at 160 academic medical centres and hospitals across 16 countries. Eligible patients were aged 12 years and older with newly-diagnosed, completely resected, and histologically confirmed stage IIB (T3b or T4a) or IIC (T4b) cutaneous melanoma; negative sentinel lymph node biopsy; and an Eastern Cooperative Oncology Group performance status of 0-1. Patients were randomly assigned (1:1) to receive either 200 mg of pembrolizumab (2 mg/kg up to a maximum of 200 mg in paediatric patients) or placebo, both intravenously, every 3 weeks for 17 cycles (part 1) or until disease recurrence or unacceptable toxicity. Eligible patients with disease recurrence could receive further treatment with pembrolizumab in the part 2 crossover or rechallenge phase. Randomisation was done using an interactive response technology system and stratified by T category and paediatric status. The primary endpoint was investigator-assessed recurrence-free survival (assessed here with longer follow-up), and we report the prespecified third interim analysis of distant metastasis-free survival (secondary endpoint). Efficacy analyses were done in the intention-to-treat population (all patients who were randomly assigned, according to assigned group) and safety was assessed in all patients who were randomly assigned and received at least one dose of trial treatment, according to the treatment received. KEYNOTE-716 is registered at ClinicalTrials.gov, NCT03553836, and has completed recruitment.

FINDINGS

Between Sept 23, 2018, and Nov 4, 2020, 976 patients were randomly assigned to receive pembrolizumab (n=487) or placebo (n=489). At a median follow-up of 27·4 months (IQR 23·1-31·7), median distant metastasis-free survival was not reached (95% CI not reached [NR]-NR) in either group. Pembrolizumab significantly improved distant metastasis-free survival (hazard ratio [HR] 0·64, 95% CI 0·47-0·88, p=0·0029) versus placebo. Median recurrence-free survival was 37·2 months (95% CI NR-NR) in the pembrolizumab group and not reached in the placebo group (95% CI NR-NR). The risk of recurrence remained lower with pembrolizumab versus placebo (HR 0·64, 95% CI 0·50-0·84). The most common grade 3 or worse adverse events were hypertension (16 [3%] of 483 patients in the pembrolizumab group vs 17 [4%] of 486 patients in the placebo group), diarrhoea (eight [2%] vs one [<1%]), rash (seven [1%] vs two [<1%]), autoimmune hepatitis (seven [1%] vs two [<1%]), and increased lipase (six [1%] vs eight [2%]). Treatment-related serious adverse events occurred in 49 (10%) patients in the pembrolizumab group and 11 (2%) patients in the placebo group. No treatment-related deaths were reported.

INTERPRETATION

Adjuvant pembrolizumab is an efficacious treatment option for resected stage IIB and IIC melanoma, with significant improvement in distant-metastasis free survival versus placebo and continued reduction in the risk of recurrence with an adverse event profile consistent with previous studies of pembrolizumab. The overall benefit-risk of pembrolizumab continues to be positive in the adjuvant setting.

FUNDING

Merck Sharp & Dohme, a subsidiary of Merck & Co.

Adjuvant pembrolizumab versus placebo in resected high-risk stage II melanoma: Health-related quality of life from the randomized phase 3 KEYNOTE-716 study

BACKGROUND

Adjuvant pembrolizumab significantly improved recurrence-free survival (RFS) versus placebo in resected stage IIB and IIC melanoma in the phase 3 KEYNOTE-716 study. Health-related quality of life (HRQoL) results are reported.

METHODS

Patients were randomly assigned 1:1 to pembrolizumab 200 mg (2 mg/kg, patients ≥12 to <18 years) Q3W or placebo for ≤17 cycles or until disease recurrence, unacceptable toxicity, or withdrawal. Change from baseline in EORTC QLQ-C30 global health status (GHS)/quality of life (QoL) was a prespecified exploratory end point. Change in EORTC QLQ-C30 functioning, symptom, and single-item scales, and EQ-5D-5L visual analog scale (VAS) were also summarized. Primary analyses were performed at week 48 to ensure adequate completion/compliance. The HRQoL population comprised patients who received ≥1 dose of treatment and completed ≥1 assessment.

RESULTS

The HRQoL population included 969 patients (pembrolizumab, n = 483; placebo, n = 486). Compliance at week 48 was ≥80% for both instruments. EORTC QLQ-C30 GHS/QoL, physical functioning, role functioning, and EQ-5D-5L VAS scores were stable from baseline to week 48 in both arms, with no clinically meaningful decline observed. Scores did not differ significantly between pembrolizumab and placebo. EORTC QLQ-C30 GHS/QoL, physical functioning, role functioning, and EQ-5D-5L VAS scores remained stable through week 96 in both arms.

CONCLUSIONS

HRQoL was stable with adjuvant pembrolizumab, with no clinically meaningful decline observed. Change from baseline in HRQoL was similar between arms. These results, in conjunction with the improved RFS and manageable safety previously reported, support the use of adjuvant pembrolizumab for high-risk stage II melanoma.

Distant metastasis-free survival with pembrolizumab versus placebo as adjuvant therapy in stage IIB or IIC melanoma: The phase 3 KEYNOTE-716 study

LBA9500

Background: In previous analyses of the phase 3, double-blind KEYNOTE-716 study, adjuvant pembrolizumab (pembro) significantly improved recurrence-free survival compared with placebo in patients (pts) with resected AJCC-8 stage IIB or IIC melanoma. We present new data from the analysis of distant metastasis-free survival (DMFS), and recurrence-free survival (RFS) with longer follow up. Methods: A total of 976 pts aged ≥12 years with complete resection of cutaneous stage IIB or IIC melanoma and negative sentinel lymph node biopsy were randomized 1:1 to pembro 200 mg (2 mg/kg for pediatric pts) or placebo Q3W for 17 cycles (approximately 1 year) in Part 1 of the study. Randomization was stratified by T category 3b, 4a, 4b (adults) with a separate stratum for pediatric pts. Treatment continued until disease recurrence or unacceptable toxicity. Pts who received placebo in Part 1, or who did not experience disease progression within 6 months of completing Part 1 were eligible for additional cycles of pembro Q3W at recurrence (Part 2). The primary endpoint was RFS per investigator. DMFS by investigator is a secondary endpoint. The data cut-off date for this interim analysis was Jan 4th, 2022. Results: At median follow-up of 26.9 mo (range, 4.6-39.2), adjuvant pembro significantly improved DMFS (HR 0.64, 95% CI, 0.47-0.88; P=0.0029; median not reached [NR] for both) vs placebo. The 24-mo DMFS rate was 88.1% vs 82.2%. There was consistent reduction in the risk of recurrence with pembro vs placebo (HR 0.64, 95% CI, 0.50-0.84) with further follow-up. The 24-mo RFS rate was 81.2% vs 72.8%. Grade ≥ 3 any-cause AEs occurred in 137 (28.4%) vs 97 (20.0%) pts in the pembro vs placebo arms. Grade ≥ 3 drug-related AEs occurred in 83 (17.2%) vs 24 (4.9%) pts. One pt in the pembro arm and 5 pts in the placebo arm died due to an any-cause AE. No deaths were drug-related. Immune-mediated AEs occurred in 182 (37.7%) vs 45 (9.3%) pts, most commonly hypothyroidism (17.2% vs 3.7%). Conclusions: Adjuvant pembrolizumab vs placebo for resected stage IIB and IIC melanoma significantly improved DMFS, with continued reduction in the risk of recurrence, and a favorable benefit-risk profile. Clinical trial information: NCT03553836.

Pembrolizumab (pembro) plus dabrafenib (dab) and trametinib (tram) in BRAFV600E/K-mutant melanoma: Long-term follow-up of KEYNOTE-022 parts 1, 2, and 3

9516

Background: KEYNOTE-022 (NCT02130466) was a phase 1/2 study of pembro + dab + tram or pembro + tram in patients (pts) with unresectable stage III/IV melanoma (parts 1-3) or solid tumors (parts 4 and 5). In previous analyses of pts with BRAFV600E/K -mutant melanoma, pembro + dab + tram was shown to have manageable safety in parts 1-3, albeit with a higher incidence of TRAEs in part 3, and substantially improved PFS, DOR, and OS vs placebo + dab + tram in part 3, although the primary end point of a statistically significant improvement in PFS was not met. Long-term follow-up of pts with BRAFV600E/K-mutant melanoma in parts 1-3 are presented. Methods: Eligible pts were ≥18 y with unresectable stage III/IV BRAFV600E/K-mutant melanoma, ≥1 measurable lesion per RECIST v1.1, ECOG PS 0/1, and no prior systemic therapy for advanced disease. In parts 1 and 2, which involved dose finding and confirmation, pts received pembro 2 mg/kg IV Q3W + dab 150 mg PO BID + tram 2 mg PO QD (MTD). In part 3, pts were randomized 1:1 to pembro + dab + tram at MTD or placebo + dab + tram. Primary end points were safety, tolerability, and MTD (parts 1 and 2); ORR per RECIST v1.1 by investigator review (part 2); and PFS per RECIST v1.1 by investigator review (part 3). Data cutoff was July 14, 2021. Results: Median (range) study follow-up was 72.9 mo (68.4-84.5) in parts 1 and 2 (n = 15) and 61.2 mo (50.7-67.5) for all pts (n = 120; 60 each arm) in part 3. Safety of pembro + dab + tram in parts 1 and 2 was consistent with prior reports; grade 3/4 TRAEs occurred in 11 pts (73%), and no additional DLTs occurred. ORR in parts 1 and 2 was 67% (95% CI, 38-88), which was similar to that reported at an earlier data cut (73% [95% CI, 45-92]); median DOR was 19.4 mo (95% CI, 2.8-NR), median OS was NR (95% CI, 10.3-NR), 48-mo OS rate was 60%, median PFS was 15.2 mo (95% CI, 4.2-NR), and 48-mo PFS rate was 28% (Ribas A et al. Nat Med. 2019;25:936-940). In part 3, median PFS was 17.0 mo (95% CI, 11.3-NR) for pembro + dab + tram vs 9.9 mo (95% CI, 6.7-15.6) for placebo + dab + tram (HR, 0.46; 95% CI, 0.29-0.74) and 24-mo PFS rate was 47% vs 16%, and median OS was 46.3 mo (95% CI, 23.9-NR) vs 26.3 mo (95% CI, 18.2-38.6); and 24-mo OS rate was 63% vs 52%, respectively. ORR was 65% (95% CI, 52-77) for pembro + dab + tram vs 72% (95% CI, 59-83) for placebo + dab + tram; median DOR was 30.2 mo (95% CI, 14.1-NR) vs 12.1 mo (95% CI, 6.0-15.7). Safety in part 3 was similar to prior reports; grade 3-5 TRAEs occurred in 42 pts (70%) in the pembro + dab + tram arm vs 27 pts (45%) in the placebo + dab + tram arm (Ferrucci PF et al. J Immunother Cancer. 2020;8:e001806). No additional grade 5 TRAEs occurred (1 grade 5 pneumonitis had occurred at prior analysis). Conclusions: At long-term follow-up, first-line pembro + dab + tram continued to show improved PFS, DOR, and OS compared with placebo + dab + tram in pts with BRAFV600E/K-mutant melanoma. TRAEs were more common with pembro + dab + tram but no new safety signals were identified. Clinical trial information: NCT02130466.

Health-related quality of life (HRQoL) with pembrolizumab (pembro) in resected high-risk stage II melanoma in the phase 3 KEYNOTE-716 study

9581

Background: Adjuvant pembro improved RFS vs placebo (HR, 0.61; 95% CI, 0.45-0.82) and had manageable safety in patients (pts) with resected high-risk stage II melanoma at second interim analysis of KEYNOTE-716 (NCT03553836). HRQoL results are presented. Methods: Pts aged ≥12 y with resected stage IIB/C melanoma were randomized 1:1 to adjuvant pembro 200 mg (2 mg/kg for pts ≥12 and < 18 y) Q3W or placebo for ≤17 cycles. Change from baseline in HRQoL was an exploratory end point. EORTC QLQ-C30 and EQ-5D-5L were administered at baseline; cycles 5, 9, 13, and 17 in y 1; every 12 wk in y 2; and every 6 mo in y 3. The HRQoL population included all pts who received ≥1 dose of study treatment and had ≥1 HRQoL assessment available. Least-squares mean (LSM) change from baseline to wk 48 in EORTC QLQ-C30 global health status (GHS)/quality of life (QoL) and physical functioning (PF) and EQ-5D-5L visual analog scale (VAS) were calculated using a constrained longitudinal data analysis model; HRQoL score was the response variable with treatment by time interaction and T stage at baseline as covariates. Empirical mean change from baseline in QLQ-C30 GHS/QoL and PF scores over time was evaluated. A ≥10-point improvement or decline in QLQ-C30 scores was considered clinically meaningful. Data cutoff was June 21, 2021. Results: Of 976 pts enrolled, 969 were included in the HRQoL population (483 pembro; 486 placebo). Median follow-up in the ITT population was 20.5 mo (range, 4.6-32.7). At wk 48, compliance (adherence) for EORTC QLQ-C30 was 83.4% for pembro and 89.3% for placebo and completion was 70.6% and 75.7%, respectively. At wk 48, compliance for EQ-5D-5L was 84.1% for pembro and 90.0% for placebo and completion was 71.2% and 76.3%, respectively. QLQ-C30 GHS/QoL and PF and EQ-5D-5L VAS scores were similar between arms at baseline. LSM change from baseline to wk 48 in QLQ-C30 GHS/QoL score was −4.49 (95% CI, −6.19 to −2.79) for pembro and −0.82 (95% CI, −2.47 to 0.83) for placebo (LSM difference: −3.67; 95% CI, −5.91 to −1.44). LSM change from baseline to wk 48 in QLQ-C30 PF score was −3.27 (95% CI, −4.61 to −1.92) for pembro and −1.77 (95% CI, −3.07 to −0.46) for placebo (LSM difference: −1.50; 95% CI, −3.33 to 0.32). LSM change from baseline to wk 48 in EQ-5D-5L VAS score was −2.19 (95% CI, −3.52 to −0.85) for pembro and −0.25 (95% CI, −1.54 to 1.04) for placebo (LSM difference: −1.94; 95% CI, −3.72 to −0.16). LSM change from baseline to wk 48 in other QLQ-C30 functioning and symptom scales was similar in both arms. Empirical mean change from baseline in QLQ-C30 GHS/QoL and PF was similar over 96 wk in both arms. Conclusions: No clinically meaningful decreases in EORTC QLQ-C30 or EQ-5D-5L VAS scores were observed for adjuvant pembro or placebo. These results, along with improved RFS and manageable safety, support the use of adjuvant pembro in resected high-risk stage II melanoma. Clinical trial information: NCT03553836.

Pembrolizumab versus placebo as adjuvant therapy in completely resected stage IIB or IIC melanoma (KEYNOTE-716): a randomised, double-blind, phase 3 trial

BACKGROUND

Pembrolizumab prolongs progression-free and overall survival among patients with advanced melanoma and recurrence-free survival in resected stage III disease. KEYNOTE-716 assessed pembrolizumab as adjuvant therapy in patients with completely resected, high-risk, stage II melanoma. We report results from the planned first and second interim analyses for recurrence-free survival.

METHODS

In this double-blind, randomised, placebo-controlled phase 3 study, involving 160 academic medical centres and hospitals in 16 countries (Australia, Belgium, Brazil, Canada, Chile, France, Germany, Israel, Italy, Japan, Poland, South Africa, Spain, Switzerland, the UK, and the USA), patients aged 12 years or older with newly diagnosed, completely resected stage IIB or IIC melanoma (TNM stage T3b or T4 with a negative sentinel lymph node biopsy) were recruited. Eligible patients were randomly assigned (1:1), in blocks of four and stratified by T-category (3b, 4a, and 4b) and paediatric status (age 12-17 years vs ≥18 years), using an interactive response technology system to intravenous pembrolizumab 200 mg (2 mg/kg in paediatric patients) or placebo every 3 weeks for 17 cycles or until disease recurrence or unacceptable toxicity. All patients, clinical investigators, and analysts were masked to treatment assignment. The primary endpoint was investigator-assessed recurrence-free survival (defined as time from randomisation to recurrence or death) in the intention-to-treat (ITT) population (ie, all patients randomly assigned to treatment). The primary endpoint was met if recurrence-free survival was significantly improved for pembrolizumab versus placebo at either the first interim analysis (after approximately 128 patients had events) or second interim analysis (after 179 patients had events) under multiplicity control. Safety was assessed in all patients randomly assigned to treatment who received at least one dose of study treatment. This study is registered with ClinicalTrials.gov, NCT03553836, and is closed to accrual.

FINDINGS

Between Sept 23, 2018, and Nov 4, 2020, 1182 patients were screened, of whom 976 were randomly assigned to pembrolizumab (n=487) or placebo (n=489; ITT population). The median age was 61 years (IQR 52-69) and 387 (40%) patients were female and 589 (60%) were male. 874 (90%) of 976 patients were White and 799 (82%) were not Hispanic or Latino. 483 (99%) of 487 patients in the pembrolizumab group and 486 (99%) of 489 in the placebo group received assigned treatment. At the first interim analysis (data cutoff on Dec 4, 2020; median follow-up of 14·4 months [IQR 10·2-18·7] in the pembrolizumab group and 14·3 months [10·1-18·7] in the placebo group), 54 (11%) of 487 patients in the pembrolizumab group and 82 (17%) of 489 in the placebo group had a first recurrence of disease or died (hazard ratio [HR] 0·65 [95% CI 0·46-0·92]; p=0·0066). At the second interim analysis (data cutoff on June 21, 2021; median follow-up of 20·9 months [16·7-25·3] in the pembrolizumab group and 20·9 months [16·6-25·3] in the placebo group), 72 (15%) patients in the pembrolizumab group and 115 (24%) in the placebo group had a first recurrence or died (HR 0·61 [95% CI 0·45-0·82]). Median recurrence-free survival was not reached in either group at either assessment timepoint. At the first interim analysis, grade 3-4 treatment-related adverse events occurred in 78 (16%) of 483 patients in the pembrolizumab groups versus 21 (4%) of 486 in the placebo group. At the first interim analysis, four patients died from an adverse event, all in the placebo group (one each due to pneumonia, COVID-19-related pneumonia, suicide, and recurrent cancer), and at the second interim analysis, one additional patient, who was in the pembrolizumab group, died from an adverse event (COVID-19-related pneumonia). No deaths due to study treatment occurred.

INTERPRETATION

Pembrolizumab as adjuvant therapy for up to approximately 1 year for stage IIB or IIC melanoma resulted in a significant reduction in the risk of disease recurrence or death versus placebo, with a manageable safety profile.

FUNDING

Merck Sharp & Dohme, a subsidiary of Merck & Co, Kenilworth, NJ, USA.

Improved pyrexia-related outcomes associated with an adapted pyrexia adverse event management algorithm in patients treated with adjuvant dabrafenib plus trametinib: Primary results of COMBI-APlus

BACKGROUND

COMBI-AD demonstrated long-term benefit of adjuvant dabrafenib plus trametinib in patients with resected stage III BRAF V600E/K-mutant melanoma; however, 9% of patients permanently discontinued therapy due to pyrexia. COMBI-APlus evaluated whether an adapted pyrexia management algorithm reduces high-grade pyrexia and pyrexia-related adverse outcomes.

METHODS

COMBI-APlus is an open-label, phase IIIb trial evaluating an adapted pyrexia management algorithm in patients with high-risk resected stage III BRAF V600E/K-mutant melanoma treated with up to 12 months of adjuvant dabrafenib plus trametinib. Both drugs were interrupted for pyrexia (temperature ≥38°C) or the occurrence of pyrexia syndrome for suspected recurrent pyrexia. Treatment was restarted at the same dose once patients were symptom free for ≥24 h. The primary endpoint was the composite rate of grade 3/4 pyrexia, hospitalisation due to pyrexia, or permanent discontinuation due to pyrexia versus historical COMBI-AD control (20.0%; 95% confidence interval [CI], 16.3%-24.1%).

RESULTS

At data cutoff (5 October 2020), COMBI-APlus met its primary endpoint of significant improvement in the composite rate of pyrexia (8.0% [95% CI, 5.9%-10.6%]), with rates of 3.8% for grade 3/4 pyrexia, 4.3% for hospitalisation due to pyrexia, and 2.4% for discontinuation due to pyrexia. Estimated 12-month relapse-free survival was 91.8% (95% CI, 89.0%-93.9%). The most common adverse events were consistent with those in COMBI-AD, and 14.7% of patients permanently discontinued treatment due to adverse events.

CONCLUSIONS

The adapted pyrexia management algorithm appears to reduce the incidence of severe pyrexia outcomes, enables patients to manage pyrexia at home, and helps patients remain on treatment.

CLINICAL TRIAL REGISTRATION

NCT03551626.

Retrospective Chart Review of Dabrafenib Plus Trametinib in Patients with Metastatic BRAF V600-Mutant Melanoma Treated in the Individual Patient Program (DESCRIBE Italy)

BACKGROUND

Real-world data on extended follow-up of patients with BRAF V600-mutant metastatic melanoma are limited. We investigated dabrafenib plus trametinib (dab + tram) outside of a clinical trial setting (Individual Patient Program; DESCRIBE Italy).

OBJECTIVE

To describe the baseline features, treatment patterns, efficacy, and safety outcomes in patients with BRAF V600-mutant unresectable or metastatic melanoma who had received dab + tram as part of the Managed Access Program (MAP) in Italy.

PATIENTS AND METHODS

An observational, retrospective chart review was conducted in Italian patients with BRAF V600-mutant unresectable stage III/IV melanoma receiving dab + tram as part of the MAP. Baseline features, treatment patterns, efficacy, and safety outcomes were evaluated.

RESULTS

Overall, 499 patients were included in this analysis. BRAF V600E mutation was seen in 81.4% of patients. Overall response rate achieved in 243 of the 390 evaluable patients was 62.3% (95% CI 57.5-67.1). Median progression-free survival (PFS) was 9.3 months (95% CI 8.6-10.6). Subgroup analyses revealed that patients with normal lactate dehydrogenase (LDH) and ≤ three metastatic sites without brain metastases at baseline had better outcomes. With normal LDH at baseline, median PFS for patients with one or two metastatic sites other than cerebral was 18 months. No new safety signals were observed. Treatment was permanently discontinued because of treatment-emergent adverse events (TEAEs) in 9.2% of patients, and pyrexia (27.3%) was the most common TEAE, with a lower incidence than that in the phase 3 studies of dab + tram.

CONCLUSION

Treatment of BRAF V600E-mutant metastatic melanoma with dab + tram in the real-world setting was effective and safe, including the unselected population with several patients having a high tumor burden - concordant with the results of the pivotal phase 3 studies of dab + tram.

KEYNOTE-022 part 3: a randomized, double-blind, phase 2 study of pembrolizumab, dabrafenib, and trametinib in BRAF-mutant melanoma

Background

In the KEYNOTE-022 study, pembrolizumab with dabrafenib and trametinib (triplet) improved progression-free survival (PFS) versus placebo with dabrafenib and trametinib (doublet) without reaching statistical significance. Mature results on PFS, duration of response (DOR), and overall survival (OS) are reported.

Methods

The double-blind, phase 2 part of KEYNOTE-022 enrolled patients with previously untreated BRAF^V600E/K-mutated advanced melanoma from 22 sites in seven countries. Patients were randomly assigned 1:1 to intravenous pembrolizumab (200 mg every 3 weeks) or placebo plus dabrafenib (150 mg orally two times per day) and trametinib (2 mg orally one time a day). Primary endpoint was PFS. Secondary endpoints were objective response rate, DOR, and OS. Efficacy was assessed in the intention-to-treat population, and safety was assessed in all patients who received at least one dose of study drug. This analysis was not specified in the protocol.

Results

Between November 30, 2015 and April 24, 2017, 120 patients were randomly assigned to triplet (n=60) or doublet (n=60) therapy. With 36.6 months of follow-up, median PFS was 16.9 months (95% CI 11.3 to 27.9) with triplet and 10.7 months (95% CI 7.2 to 16.8) with doublet (HR 0.53; 95% CI 0.34 to 0.83). With triplet and doublet, respectively, PFS at 24 months was 41.0% (95% CI 27.4% to 54.2%) and 16.3% (95% CI 8.1% to 27.1%); median DOR was 25.1 months (95% CI 14.1 to not reached) and 12.1 months (95% CI 6.0 to 15.7), respectively. Median OS was not reached with triplet and was 26.3 months with doublet (HR 0.64; 95% CI 0.38 to 1.06). With triplet and doublet, respectively, OS at 24 months was 63.0% (95% CI 49.4% to 73.9%) and 51.7% (95% CI 38.4% to 63.4%). Grade 3–5 treatment-related adverse events (TRAEs) occurred in 35 patients (58%, including one death) receiving triplet and 15 patients (25%) receiving doublet.

Conclusion

In BRAF^V600E/K-mutant advanced melanoma, pembrolizumab plus dabrafenib and trametinib substantially improved PFS, DOR, and OS with a higher incidence of TRAEs. Interpretation of these results is limited by the post hoc nature of the analysis.

Body mass index (BMI) and outcome of metastatic melanoma patients receiving targeted therapy and immunotherapy: a multicenter international retrospective study

BACKGROUND

Obesity is a risk factor for malignancy; however, its prognostic role in patients with metastatic melanoma is controversial. We aim to investigate the prognostic role of body mass index (BMI) in patients with metastatic melanoma receiving mitogen-activated pathway kinase inhibitors (MAPKi), immune checkpoint inhibitors (ICIs) alone or their sequence.

METHODS

Data on patients with metastatic melanoma receiving ≥1 line of systemic treatment were retrieved from prospectively collected databases. Progression-free survival (PFS) and overall survival (OS) were analyzed by means of multivariable stratified Cox regression models; disease control rate (DCR) was analyzed by multivariable stratified logistic regression models. Subgroup analyzes according to the type of treatments received, and in BRAF-mutated patients were pre-planned. All multivariable models included BMI, age, gender, American Joint Committee on Cancer stage, performance status, lactate dehydrogenase and treatment sequencing strategy as covariates.

RESULTS

Between November 2010 and November 2018, 688 patients from three Italian and two Polish centers were enrolled. 379 (57%) patients had M1c/d disease, 273 (41%) were female and the mean BMI was 27.1 (SD=4.9). Considering first-line treatment, 446 patients (66.8%) received ICIs and 222 MAPKi. No impact of BMI on OS was detected either considering the first line of ICIs, or ICIs sequencing (HR=1.02, 95% CI: 0.99 to 1.05, p=0.202, and HR=1.02, 95% CI: 0.99 to 1.04, p=0.237, respectively). A late effect of BMI on OS was found in patients treated with MAPKi: for five units increment, a 51% of risk reduction at 18 months and a 76% of risk reduction at 30 months were observed. No significant effect of BMI on PFS and DCR was found in any of the subgroup analyzes.

CONCLUSION

In patients with metastatic melanoma receiving ICIs, there is no impact of BMI on DCR, PFS and OS. The late prognostic effect of BMI in patients treated with MAPKi should be considered hypothesis generating and needs to be further investigated.

Toxicity of carbon ion radiotherapy and immune checkpoint inhibitors in advanced melanoma

We analyzed CTCAE adverse events of sequential Carbon Ion radiotherapy (CIRT) and immune checkpoint inhibitors (ICIs) in advanced melanoma patients. The frequencies of early and late adverse events (AEs) were 100% and 82% of patients, respectively. The frequency of G3+ AEs was in line with the literature.

Adjuvant nivolumab for stage III/IV melanoma: evaluation of safety outcomes and association with recurrence-free survival

BACKGROUND

Several therapeutic options are now available in the adjuvant melanoma setting, mandating an understanding of their benefit‒risk profiles in order to make informed treatment decisions. Herein we characterize adjuvant nivolumab select (immune-related) treatment-related adverse events (TRAEs) and evaluate possible associations between safety and recurrence-free survival (RFS) in the phase III CheckMate 238 trial.

METHODS

Patients with resected stage IIIB-C or IV melanoma received nivolumab 3 mg/kg every 2 weeks (n=452) or ipilimumab 10 mg/kg every 3 weeks for four doses and then every 12 weeks (n=453) for up to 1 year or until disease recurrence, unacceptable toxicity, or consent withdrawal. First-occurrence and all-occurrence select TRAEs were analyzed within discrete time intervals: from 0 to 3 months of treatment, from >3-12 months of treatment, and from the last dose (regardless of early or per-protocol treatment discontinuation) to 100 days after the last dose. Possible associations between select TRAEs and RFS were investigated post randomization in 3-month landmark analyses and in Cox model analyses (including a time-varying covariate of select TRAE), within and between treatment groups.

RESULTS

From the first nivolumab dose to 100 days after the last dose, first-occurrence select TRAEs were reported in 67.7% (306/452) of patients. First-occurrence select TRAEs were reported most frequently from 0 to 3 months (48.0%), during which the most common were pruritus (15.5%) and diarrhea (15.3%). Most select TRAEs resolved within 6 months. There was no clear association between the occurrence (or not) of select TRAEs and RFS by landmark analysis or by Cox model analysis within treatment arms or comparing nivolumab to the ipilimumab comparator arm.

CONCLUSION

Results of this safety analysis of nivolumab in adjuvant melanoma were consistent with its established safety profile. In the discrete time intervals evaluated, most first-occurrence TRAEs occurred early during treatment and resolved. No association between RFS and select TRAEs was evident.

TRIAL REGISTRATION NUMBER

NCT02388906.

Characterization and management of neurological adverse events during immune-checkpoint inhibitors treatment: an Italian multicentric experience

BACKGROUND

Neurological immune-related adverse events (nirAEs) are rare toxicities of immune-checkpoint inhibitors (ICI). With the increase of ICI oncological indications, their incidence is growing. Their recognition and management remain nevertheless challenging.

METHODS

A national, web-based database was built to collect cases of neurological symptoms in patients receiving ICI and not attributable to other causes after an adequate workup.

RESULTS

We identified 27 patients who developed nirAEs (20 males, median age 69 years). Patients received anti-PD1/PDL1 (78%), anti-CTLA4 (4%), or both (19%). Most common cancers were melanoma (30%) and non-small cell lung cancer (26%). Peripheral nervous system was mostly affected (78%). Median time to onset was 43.5 days and was shorter for peripheral versus central nervous system toxicities (36 versus 144.5 days, p = 0.045). Common manifestations were myositis (33%), inflammatory polyradiculoneuropathies (33%), and myasthenia gravis (19%), alone or in combination, but the spectrum of diagnoses was broad. Most patients received first-line glucocorticoids (85%) or IVIg (15%). Seven patients (26%) needed second-line treatments. At last follow-up, four (15%) patients were deceased (encephalitis, 1; myositis/myasthenia with concomitant myocarditis, 2; acute polyradiculoneuropathy, 1), while seven (26%) had a complete remission, eight (30%) partial improvement, and six (22%) stable/progressing symptoms. ICI treatment was discontinued in most patients (78%).

CONCLUSIONS

Neurological irAEs are rare but potentially fatal. They primarily affect neuromuscular structures but encompass a broad range of presentations. A prompt recognition is mandatory to timely withheld immunotherapy and administrate glucocorticoids. In corticoresistant or severely affected patients, second-line treatments with IVIg or plasmapheresis may result in additional benefit.

Liquid biopsy and radiological response predict outcomes following discontinuation of targeted therapy in patients with BRAF mutated melanoma

BACKGROUND

Outcomes of patients with metastatic melanoma discontinuing BRAF-targeted therapy for cumulative toxicity after sustained response are unknown.

PATIENTS AND METHODS

This retrospective case series analysis conducted at a single Cancer Center in Italy included patients with BRAF mutated metastatic melanoma treated with a BRAF inhibitor as a single agent or in combination with a MEK inhibitor between June 1, 2011 and January 1, 2020 and interrupting treatment after achieving complete response (CR) or long-lasting partial response (PR - i.e. > 12 months) due to cumulative toxicity.

RESULTS

We included 24 patients with a median treatment duration of 59.4 months (95%CI 55.4-63.4 - range 12-88). CR and PR were achieved in 71% and 29% of patients, respectively. At a median follow-up after treatment discontinuation of 37.8 months (95%CI 33.7-41.9), 12-months progression free survival after discontinuation (dPFS) rate was 70.8% (95%CI 54.8 - 91.6) and 24-months dPFS rate was 58.3% (95%CI 41.6 - 81.8). Baseline patients and tumor characteristics as well as treatment duration and best response did not significantly impact on dPFS. Patients with CR and negative circulating tumor DNA (ctDNA) at time of discontinuation had a significantly improved dPFS compared to patients with either radiological residual disease or ctDNA positivity (P = 0.007). No patient in CR with undetectable ctDNA experienced progression.

CONCLUSION

The risk of progression is high even in patients with sustained sensitivity to BRAF/MEK inhibitors. Integration of liquid biopsy in clinical trials investigating optimal management of patients with sustained sensitivity to BRAF/MEK inhibitors is warranted.

IMPLICATIONS FOR PRACTICE

Outcomes of patients with metastatic melanoma discontinuing BRAF-targeted therapy for cumulative toxicity are unknown. We analyzed patients with sustained responses (median treatment duration 59.4 months). Twelve and 24-months progression free survival following discontinuation were 70.8% and 58.3% respectively. Complete response and negative ctDNA at time of discontinuation are promising prognostic biomarkers in this setting.

Survival in Patients With Sentinel Node-Positive Melanoma With Extranodal Extension

BACKGROUND

Prognostic parameters in sentinel node (SN)-positive melanoma are important indicators to identify patients at high risk of recurrence who should be candidates for adjuvant therapy. We aimed to evaluate the presence of melanoma cells beyond the SN capsule-extranodal extension (ENE)-as a prognostic factor in patients with positive SNs.

METHODS

Data from 1,047 patients with melanoma and positive SNs treated from 2001 to 2020 at the Istituto Nazionale dei Tumori in Milano, Italy, were retrospectively investigated. Kaplan-Meier survival and crude cumulative incidence of recurrence curves were estimated. A multivariable logistic model was used to investigate the association between ENE and selected predictive factors. Cox models estimated the effect of the selected predictors on survival endpoints.

RESULTS

Median follow-up was 69 months. The 5-year overall survival rate was 62.5% and 71.7% for patients with positive SNs with and without ENE, respectively. The 5-year disease-free survival rate was 54.0% and 64.0% for patients with positive SNs with and without ENE, respectively. The multivariable logistic model showed that age, size of the main metastatic focus in the SN, and numbers of metastatic non-SNs were associated with ENE (all P<.0001). The multivariable Cox regression models showed the estimated prognostic effects of ENE associated with age, ulceration, size of the main metastatic focus in the SN, and number of metastatic non-SNs (all P<.0001) on disease-free survival and overall survival.

CONCLUSIONS

ENE was a significant prognostic factor in patients with positive-SN melanoma. This parameter may be useful in clinical practice as a selection criterion for adjuvant treatment in patients with stage IIIA disease with a tumor burden <1 mm in the SN. We recommend its inclusion as an independent prognostic determinant in future updates of melanoma guidelines.

Primary Analysis and 4-Year Follow-Up of the Phase III NIBIT-M2 Trial in Melanoma Patients With Brain Metastases

PURPOSE

Phase II trials have shown encouraging activity with ipilimumab plus fotemustine and ipilimumab plus nivolumab in melanoma brain metastases. We report the primary analysis and 4-year follow-up of the NIBIT-M2 study, the first phase III trial comparing these regimens with fotemustine in patients with melanoma with brain metastases.

PATIENTS AND METHODS

This phase III study recruited patients 18 years of age and older with BRAF wild-type or mutant melanoma, and active, untreated, asymptomatic brain metastases from nine centers, randomized (1:1:1) to fotemustine, ipilimumab plus fotemustine, or ipilimumab plus nivolumab. The primary endpoint was overall survival (OS).

RESULTS

From January, 2013 to September, 2018, 27, 26, and 27 patients received fotemustine, ipilimumab plus fotemustine, and ipilimumab plus nivolumab. Median OS was 8.5 months [95% confidence interval (CI), 4.8-12.2] in the fotemustine arm, 8.2 months (95% CI, 2.2-14.3) in the ipilimumab plus fotemustine arm (HR vs. fotemustine, 1.09; 95% CI, 0.59-1.99; P = 0.78), and 29.2 months (95% CI, 0-65.1) in the ipilimumab plus nivolumab arm (HR vs. fotemustine, 0.44; 95% CI, 0.22-0.87; P = 0.017). Four-year survival rate was significantly higher for ipilimumab plus nivolumab than fotemustine [(41.0%; 95% CI, 20.6-61.4) vs. 10.9% (95% CI, 0-24.4; P = 0.015)], and was 10.3% (95% CI, 0-22.6) for ipilimumab plus fotemustine. In the fotemustine, ipilimumab plus fotemustine, and ipilimumab plus nivolumab arms, respectively, 11 (48%), 18 (69%), and eight (30%) patients had treatment-related grade 3 or 4 adverse events, without treatment-related deaths.

CONCLUSIONS

Compared with fotemustine, ipilimumab plus nivolumab significantly improved overall and long-term survival of patients with melanoma with asymptomatic brain metastases.

Anticancer innovative therapy congress: Highlights from the 10th anniversary edition

During the Tenth Edition of the Annual Congress on "Anticancer Innovative Therapy" [Milan, 23/24 January 2020], experts in the fields of immuno-oncology, epigenetics, tumor cell signaling, and cancer metabolism shared their latest knowledge on the roles of i] epigenetics, and in particular, chromatin modifiers, ii] cancer metabolism, iii] cancer stem cells [CSCs], iv] tumor cell signaling, and iv] the immune system. The novel therapeutic approaches presented included epigenetic drugs, cell cycle inhibitors combined with ICB, antibiotics and other off-label drugs, small-molecules active against CSCs, liposome-delivered miRNAs, tumor-specific CAR-T cells, and T-cell-based immunotherapy. Moreover, important evidence on possible mechanisms of resistance to these innovative therapies were also discussed, in particular with respect to resistance to ICB. Overall, this conference provided scientists and clinicians with a broad overview of future challenges and hopes to improve cancer treatment reasonably in the medium-short term.

Overall survival at 5 years of follow-up in a phase III trial comparing ipilimumab 10 mg/kg with 3 mg/kg in patients with advanced melanoma

BACKGROUND

We have previously reported significantly longer overall survival (OS) with ipilimumab 10 mg/kg versus ipilimumab 3 mg/kg in patients with advanced melanoma, with higher incidences of adverse events (AEs) at 10 mg/kg. This follow-up analysis reports a 5-year update of OS and safety.

METHODS

This randomized, multicenter, double-blind, phase III trial included patients with untreated or previously treated unresectable stage III or IV melanoma. Patients were randomly assigned (1:1) to ipilimumab 10 mg/kg or 3 mg/kg every 3 weeks for 4 doses. The primary end point was OS.

RESULTS

At a minimum follow-up of 61 months, median OS was 15.7 months (95% CI 11.6 to 17.8) at 10 mg/kg and 11.5 months (95% CI 9.9 to 13.3) at 3 mg/kg (HR 0.84, 95% CI 0.71 to 0.99; p=0.04). In a subgroup analysis, median OS of patients with asymptomatic brain metastasis was 7.0 months (95% CI 4.0 to 12.8) in the 10 mg/kg group and 5.7 months (95% CI 4.2 to 7.0) in the 3 mg/kg group. In patients with wild-type or mutant BRAF tumors, median OS was 13.8 months (95% CI 10.2 to 17.0) and 33.2 months (95% CI 19.4 to 45.2) in the 10 mg/kg group, and 11.2 months (95% CI 9.2 to 13.8) and 19.7 months (95% CI 11.6 to 25.3) in the 3 mg/kg group, respectively. The incidence of grade 3/4 treatment-related AEs was 36% in the 10 mg/kg group vs 20% in the 3 mg/kg group, and deaths due to treatment-related AEs occurred in four (1%) and two patients (1%), respectively.

CONCLUSIONS

This 61-month follow-up of a phase III trial showed sustained long-term survival in patients with advanced melanoma who started metastatic treatment with ipilimumab monotherapy, and confirmed the significant benefit for those who received ipilimumab 10 mg/kg vs 3 mg/kg. These results suggest the emergence of a plateau in the OS curve, consistent with previous ipilimumab studies.

TRIAL REGISTRATION NUMBER

NCT01515189.

Analysis of patients (pts) with in-transit metastases treated with nivolumab (NIVO) or ipilimumab (IPI) in CheckMate 238

9569

Background: In the phase 3 CheckMate 238 study, NIVO has demonstrated improved recurrence-free survival (RFS) and distant metastasis-free survival (DMFS) vs IPI in pts with resected stage IIIB–C or IV melanoma, which was sustained at the 4-y analysis. Having in-transit metastases/satellites (ITM) is a poor prognostic factor, and pts with ITM are generally omitted from clinical trials. This study was the first and only adjuvant checkpoint inhibitor trial to include pts with ITM. Here, we present post hoc outcomes in this subgroup. Methods: Pts aged ≥15 y with completely resected stage IIIB–C or IV melanoma stratified by stage and tumor PD-L1 status were randomized 1:1 to NIVO (3 mg/kg Q2W; n = 453) or IPI (10 mg/kg Q3W for 4 doses, Q12W thereafter; n = 453) for a maximum of 1 y or until disease recurrence/unacceptable toxicity. Pts with ITM, with or without synchronous nodal involvement, were included. The primary study endpoint was RFS; overall survival (OS) was a secondary endpoint; and DMFS was exploratory. Results: Each of the 2 treatment groups had 164 pts with ITM. Baseline characteristics were generally similar between treatment groups in pts with or without ITM; in pts with ITM vs without ITM, tumor ulceration was less frequent in NIVO-treated pts, and fewer IPI-treated pts had PD-L1 expression ≥5%. RFS and DMFS favored NIVO vs IPI in all ITM subgroups (table). OS was similar to the intention-to-treat (ITT) population with no differences noted between treatment groups or between ITM subgroups. Among pts with or without ITM, dominant metastatic sites were lung and lymph nodes, followed by brain, liver, and soft tissue (in varying order). Similar metastasis patterns were observed in pts with ITM regardless of nodal involvement. Treatment-related adverse events (any grade and grade 3/4) in pts with ITM were similar to those of the ITT population. Conclusions: Results of this post hoc 4-y analysis of CheckMate 238 showed that safety and efficacy were similar in pts with or without ITM, supporting the use of adjuvant NIVO in pts with ITM, regardless of nodal involvement. Clinical trial information: NCT02388906. [Table: see text]

Improved pyrexia-related outcomes associated with an adapted pyrexia adverse event (AE) management algorithm in patients (pts) treated with adjuvant dabrafenib + trametinib (dab + tram): Primary results of COMBI-APlus

9525

Background: The long-term benefit of adjuvant dab + tram in pts with resected stage III BRAF V600E/K–mutant melanoma was demonstrated in COMBI-AD where AEs led to permanent discontinuation of dab + tram in 26% of pts, most often due to pyrexia (9%). The COMBI-APlus trial (NCT03551626) is designed to evaluate whether an adapted pyrexia management algorithm could reduce high-grade pyrexia and other pyrexia-related adverse outcomes, such as treatment cessation and hospitalization. Methods: COMBI-APlus is an open-label, Phase IIIb trial evaluating an adapted pyrexia management algorithm in pts with high-risk resected stage III BRAF V600E/K–mutant melanoma treated with 12 mo of adjuvant dab + tram. In the adapted algorithm, both dab and tram were interrupted promptly at the onset of pyrexia (temperature ≥ 38°C). In the event of suspected recurrent pyrexia, treatment may be interrupted in the presence of pyrexia syndrome (ie, chills, rigors, night sweats, or influenza-like symptoms without temperature ≥ 38°C) at investigator discretion. Treatment with dab + tram was restarted at the same dose level once pts were symptom free for ≥ 24 hours. The primary endpoint is the composite rate of grade 3/4 pyrexia, hospitalization due to pyrexia, or permanent discontinuation due to pyrexia vs a historical control from COMBI-AD (20%; 95% CI, 16.3%-24.1%). Secondary endpoints include relapse-free survival (RFS) and safety. Results: A total of 552 pts were enrolled. At the data cutoff (5 Oct 2020), all pts had completed 12 mo of treatment; median duration of follow-up was 18.4 mo. COMBI-APlus met its primary endpoint of significant improvement in composite rate of pyrexia. The composite rate was 8.0% (95% CI, 5.9%-10.6%), with rates of 3.8% for grade 3/4 pyrexia, 4.3% for hospitalization due to pyrexia, and 2.4% for discontinuation due to pyrexia. The estimated 12-mo RFS rate was 91.8% (95% CI, 89.0%-93.9%). The most common AEs (≥ 20%) were pyrexia (67.8%), headache (31.7%), blood creatine phosphokinase increase (27.9%), diarrhoea (27.0%), chills (26.4%), fatigue (25.7%), asthenia (23.6%), nausea (23.4%), rash (21.4%), and arthralgia (21.0%). AEs of any type led to permanent dab + tram discontinuation in 14.7% of pts. Conclusions: This primary analysis suggests the new adapted pyrexia management algorithm is effective in reducing grade 3/4 pyrexia, pyrexia-related hospitalization, and treatment discontinuation in pts receiving adjuvant dab + tram. The early efficacy appears consistent with that observed in COMBI-AD. The growing experience of oncologists in managing pyrexia with this simple algorithm may reduce the need for hospitalization or visits to a healthcare provider, which is highly desirable during the current COVID-19 pandemic. Thus, more pts can remain on treatment and derive benefit. Clinical trial information: NCT03551626.

Back to simplicity: a four-marker blood cell score to quantify prognostically relevant myeloid cells in melanoma patients

Background

Myeloid-derived suppressor cells (MDSC), a cornerstone of cancer-related immunosuppression, influence response to therapy and disease outcomes in melanoma patients. Nevertheless, their quantification is far from being integrated into routine clinical practice mostly because of the complex and still evolving phenotypic signatures applied to define the cell subsets. Here, we used a multistep downsizing process to verify whether a core of few markers could be sufficient to capture the prognostic potential of myeloid cells in peripheral blood mononuclear cells (PBMC) of metastatic melanoma patients.

Methods

In baseline frozen PBMC from a total of 143 stage IIIc to IV melanoma patients, we first assessed the relevant or redundant expression of myeloid and MDSC-related markers by flow cytometry (screening set, n=23 patients). Subsequently, we applied the identified panel to the development set samples (n=59 patients undergoing first/second-line therapy) to obtain prognostic variables associated with overall survival (OS) and progression-free survival (PFS) by machine learning adaptive index modeling. Finally, the identified score was confirmed in a validation set (n=61) and compared with standard clinical prognostic factors to assess its additive value in patient prognostication.

Results

This selection process led to the identification of what we defined myeloid index score (MIS), which is composed by four cell subsets (CD14⁺, CD14⁺HLA-DR^neg, CD14⁺PD-L1⁺ and CD15⁺ cells), whose frequencies above cut-offs stratified melanoma patients according to progressively worse prognosis. Patients with a MIS=0, showing no over-threshold value of MIS subsets, had the best clinical outcome, with a median survival of >33.6 months, while in patients with MIS 1→3, OS deteriorated from 10.9 to 6.8 and 6.0 months as the MIS increased (p<0.0001, c-index=0.745). MIS clustered patients into risk groups also according to PFS (p<0.0001). The inverse correlation between MIS and survival was confirmed in the validation set, was independent of the type of therapy and was not interfered by clinical prognostic factors. MIS HR was remarkably superior to that of lactate dehydrogenase, tumor burden and neutrophil-to-lymphocyte ratio.

Conclusion

The MIS >0 identifies melanoma patients with a more aggressive disease, thus acting as a simple blood biomarker that can help tailoring therapeutic choices in real-life oncology.

miR-146a-5p impairs melanoma resistance to kinase inhibitors by targeting COX2 and regulating NFkB-mediated inflammatory mediators

Background

Targeted therapy with BRAF and MEK inhibitors has improved the survival of patients with BRAF-mutated metastatic melanoma, but most patients relapse upon the onset of drug resistance induced by mechanisms including genetic and epigenetic events. Among the epigenetic alterations, microRNA perturbation is associated with the development of kinase inhibitor resistance. Here, we identified and studied the role of miR-146a-5p dysregulation in melanoma drug resistance.

Methods

The miR-146a-5p-regulated NFkB signaling network was identified in drug-resistant cell lines and melanoma tumor samples by expression profiling and knock-in and knock-out studies. A bioinformatic data analysis identified COX2 as a central gene regulated by miR-146a-5p and NFkB. The effects of miR-146a-5p/COX2 manipulation were studied in vitro in cell lines and with 3D cultures of treatment-resistant tumor explants from patients progressing during therapy.

Results

miR-146a-5p expression was inversely correlated with drug sensitivity and COX2 expression and was reduced in BRAF and MEK inhibitor-resistant melanoma cells and tissues. Forced miR-146a-5p expression reduced COX2 activity and significantly increased drug sensitivity by hampering prosurvival NFkB signaling, leading to reduced proliferation and enhanced apoptosis. Similar effects were obtained by inhibiting COX2 by celecoxib, a clinically approved COX2 inhibitor.

Conclusions

Deregulation of the miR-146a-5p/COX2 axis occurs in the development of melanoma resistance to targeted drugs in melanoma patients. This finding reveals novel targets for more effective combination treatment.