Efficacy of atezolizumab concurrent with radiotherapy in patients with muscle-invasive bladder cancer (MIBC) (SOGUG-2017-A-IEC(VEJ)-4)

TPS601

Background: Radical cystectomy (RC) is the standard of care for patients with T2-T4a MIBC. Organ-preserving treatment is an alternative for patients who wish to attempt bladder preservation therapy or are ineligible for cystectomy. This includes maximal transurethral resection of bladder tumour, external beam radiation therapy (EBRT) and concurrent chemotherapy. The 5 and 10 year OS and disease specific survival (DSS) rates in contemporary RC series are comparable to that reported in bladder-preserving series. Due to EBRT can mediate inmunoestimulatory effects and that radiotherapy has been used in combination with different treatment regimens, a considerable interest has been attracted by combinatorial regimens involving EBRT plus checkpoint inhibitors. The purpose of the present study is to explore feasibility and activity of the combination of atezolizumab associated with EBRT after TURBT in the treatment of localized MIBC with preservation intent. Methods: The primary endpoint of this study is to assess the efficacy of atezolizumab concurrent with EBRT in terms of pathological complete response. The secondary endpoints include OS, DSS, disease free survival, bladder intact disease-free survival, number of patients (pts) with muscle invasive and non-muscle invasive local failure, the rate of distance metastases, the rate of pts with bladder preserved, the rate of immediate or late salvage cystectomy and safety profile and tolerability of the combination. Biomarkers will be evaluated as exploratory endpoints. Elegibility criteria include pts with histologically-confirmed diagnosis of MIBC in clinical stages T2-4a N0 M0, who are not candidates for radical cystectomy by medical reasons, refusal or patient’s choice, unfit for cisplatin and PS (ECOG) 0-2. Pts will receive atezolizumab 1.200 mg by IV infusion on Day1 of each cycle every 3 weeks for a total of 6 treatment courses, concurrent with EBRT 60 Gy in 30 fractions over 6 weeks at 2 Gy/day. With 35 evaluable pts and a pCR of 80%, the 95%CI of the estimation would be 0.62–0.92. The study will be stopped if we do not achieve at least 9 pCR among the first 13 evaluable pts. Otherwise, the study will continue until 39 pts. Clinical trial information: 2018-004348-47.

Dabrafenib plus trametinib for compassionate use in metastatic melanoma: A STROBE-compliant retrospective observational postauthorization study

The main objective of the study was to evaluate the efficacy and safety of dabrafenib alone or combined with trametinib for compassionate use in patients with metastatic melanoma.This retrospective, observational study involved 135 patients with unresectable stage IIIC or stage IV melanoma from an expanded-access program at 30 Spanish centers.Forty-eight patients received dabrafenib monotherapy and 87 received combination dabrafenib and trametinib; 4.4% and 95.6% of the patients had stage IIIC and IV melanoma, respectively. All patients showed BRAF mutations in their primary or metastatic lesions; 3 were positive for V600K while the remainder had V600E or V600+. A positive response to treatment was reported in 89.3% of the patients. Overall survival rates at 12 and 24 months were 59.6% (95% confidence interval [CI], 52.5-68.9%) and 36.4% (95% CI, 27.8-45%), respectively. Progression-free survival rates at 12 and 24 months were 39.3% (95% CI, 31.1-47.5%) and 21.6% (95% CI, 14.5-28.7%), respectively. Fifty-seven patients (42.2%) reported cutaneous toxicity of any type, mainly hyperkeratosis (14.8%) and rash (11.9%). The most frequent adverse events were pyrexia (27.4%), asthenia (19.3%), arthralgia (16.9%), and diarrhoea (13.2%).Our results suggest that both dabrafenib alone or in combination with trametinib are effective for compassionate use in terms of response and/or survival rates. However, differences in patients' prognostic features ought to be considered. No new findings were revealed regarding the safety profiles of either regimen. This is the first study to evaluate the efficacy of these 2 selective BRAF and mitogen-activated extracellular signal-regulated kinase inhibitors in a real-world setting in Spain.