SUMMARY: The FDA on May 22, 2020 approved approved ALUNBRIG® (Brigatinib) for the first-line treatment of patients with ALK-positive metastatic Non Small Cell Lung Cancer (NSCLC), as detected by an FDA-approved test. Lung cancer is the second most common cancer in both men and women and accounts for about 14% of all new cancers and 27% of all cancer deaths. The American Cancer Society estimates that for 2020, about 228, 820 new cases of lung cancer will be diagnosed and 135,720 patients will die of the disease. Lung cancer is the leading cause of cancer-related mortality in the United States. Non-Small Cell Lung Cancer (NSCLC) accounts for approximately 85% of all lung cancers. Of the three main subtypes of NSCLC, 30% are Squamous Cell Carcinomas (SCC), 40% are Adenocarcinomas and 10% are Large Cell Carcinomas. With changes in the cigarette composition and decline in tobacco consumption over the past several decades, Adenocarcinoma now is the most frequent histologic subtype of lung cancer.
The discovery of rearrangements of the Anaplastic Lymphoma Kinase (ALK) gene in some patients with advanced NSCLC and adenocarcinoma histology, led to the development of agents such as XALKORI® (Crizotinib), ZYKADIA® (Ceritinib), ALECENSA® (Alectinib) and ALUNBRIG® (Brigatinib), with promising results. It has become clear that appropriate, molecularly targeted therapy for tumors with a molecular abnormality, results in the best outcomes. According to the US Lung Cancer Mutation Consortium (LCMC), two thirds of patients with advanced adenocarcinoma of the lung, have a molecular driver abnormality. The most common oncogenic drivers in patients with advanced adenocarcinoma of the lung are, KRAS in 25%, EGFR in 21% and ALK in 8% as well as other mutations in BRAF, HER2, AKT1 and fusions involving RET and ROS oncogenes. These mutations are mutually exclusive, and the presence of two simultaneous mutations, are rare.
The new approval for ALUNBRIG® was based on results from the Phase III ALTA 1L (ALK in Lung Cancer Trial of BrigAtinib in 1st Line) trial, which is a global, ongoing, randomized, open-label, comparative, multicenter study, in which investigators compared the efficacy and safety of ALUNBRIG® with XALKORI® (Crizotinib) in 275 patients with Stage IIIB/IV ALK positive, locally advanced or metastatic NSCLC, who have not received prior treatment with an ALK inhibitor, but may have received 1 prior regimen of chemotherapy or no chemotherapy in the advanced setting. Patients were randomized 1:1 to receive either ALUNBRIG® 180 mg orally once daily (N=137), with a 7-day lead-in period at 90 mg, or XALKORI® 250 mg orally twice daily (N=138). Crossover from the XALKORI® arm to receive ALUNBRIG® was permitted at BICR (Blinded Independent Review Committee)-assessed Progression Free Survival (PFS). The median age was 59 years, and 55% of patients were female. Twenty-nine percent had brain metastases at baseline with comparable pre-enrollment central nervous system (CNS) radiotherapy rates among both cohorts. Overall, 27% of patients had prior chemotherapy in the locally advanced or metastatic setting. The Primary endpoint was BIRC assessed PFS and Secondary endpoints included Objective Response Rate (ORR), Intracranial ORR, Intracranial PFS, Overall Survival (OS), safety, and tolerability.
At a median follow up of 25 months, it was noted that ALUNBRIG® reduced the risk of disease progression or death by 51% compared with XALKORI® (HR=0.49; P=0.0007), with a median PFS of 24 months as assessed by a BIRC versus 11 months for XALKORI®. The confirmed ORR as assessed by BIRC was 74% with ALUNBRIG® and 62% for XALKORI®. The median duration of response (DOR) was not reached, and 13.8 months with ALUNBRIG® and XALKORI®, respectively.
After more than two years of follow-up, ALUNBRIG® demonstrated superiority over XALKORI®, with significant anti-tumor activity observed, especially in patients with baseline brain metastases. The confirmed intracranial ORR for patients with measurable brain metastases at baseline, treated with ALUNBRIG® was 78% versus 26% for patients treated with XALKORI®. The median intracranial Duration of Response in confirmed responders with measurable brain metastases at baseline was Not Reached with ALUNBRIG® and 9.2 months with XALKORI®, respectively. The median intracranial PFS was 24 months with ALUNBRIG®, compared with 5.6 months for XALKORI®. ALUNBRIG® reduced the risk of intracranial disease progression or death by 69% in patients who had brain metastases at baseline (HR=0.31).
Additionally, patients in the ALUNBRIG® group also experienced significant improvements in Health-Related Quality of Life, with delay in the median time to worsening in Global Health Score by 27 months versus 8 months with XALKORI®, as well as delay in the time to worsening and prolonged duration of improvement in fatigue, nausea and vomiting, appetite loss, and emotional and social functioning. Further, the duration of improvement in QoL with ALUNBRIG® was Not Reached versus 12 months with XALKORI®.
It was concluded that ALUNBRIG® demonstrated a statistically and clinically significant improvement in Progression Free Survival when compared to XALKORI® in ALK inhibitor-naïve, ALK positive NSCLC, with superior efficacy especially among those with brain metastases at baseline.
Brigatinib vs crizotinib in patients with ALK inhibitor-naive advanced ALK+ NSCLC: Updated results from the phase III ALTA-1L trial. Camidge R, Kim HR, Ahn M, et al. Presented at the 2019 ESMO Asia Congress, November 23, 2019.