FDA Grants Lorlatinib a Priority Review for Lung Cancer Treatment
Lorlatinib was granted a priority review to a new drug application (NDA) for patients with ALK-positive metastatic non–small cell lung cancer (NSCLC) who have progressed on one or more ALK tyrosine kinases inhibitors (TKIs).
The priority review follows a breakthrough therapy designation awarded in April 2017, and the FDA is now scheduled under the Prescription Drug User Fee Act to make its final decision by August 2018. Pfizer, the developer of the third-generation ALK inhibitor lorlatinib, announced in a press release that the European Medicines Agency and the Japan Pharmaceutical and Medical Devices Agency have also accepted applications to market lorlatinib for this indication.
In support of the three applications, Pfizer submitted data from the phase 2 part of a phase 1/2 trial in which the overall response rate (ORR) was 69 percent in ALK-positive patients previously treated with Xalkori (crizotinib) with or without chemotherapy, and the Intracranial ORR (IC-ORR) was 68.
ALK-positive patients previously treated with a non- Xalkori ALK inhibitor with or without chemotherapy had an ORR of 33 percent and the IC-ORR was 42 percent. In ALK-positive patients previously treated with two or three ALK inhibitors with or without chemotherapy, ORR was 39 percent and IC-ORR was 48 percent.
“Treatment resistance resulting in disease progression is a major challenge faced by patients with ALK-positive metastatic NSCLC. Lorlatinib was developed by Pfizer scientists with the specific goal of overcoming resistance to first- and second-generation ALK-targeted therapies,” Mace Rothenberg, M.D., chief development officer, Oncology, Pfizer Global Product Development, said in a statement. “The encouraging results observed in a variety of patients previously treated with ALK inhibitors provides the basis for these applications.”
In the phase 2 study, 275 patients with or without asymptomatic, untreated or treated brain metastases were enrolled in six cohorts based on biomarker status, ALK-positivity, ROS1-positivity, and prior therapy.
Beyond the efficacy in pretreated patients, the results also showed that lorlatinib induced an ORR of 90 percent in treatment-naïve patients with ALK-positive NSCLC. The IC-ORR was 75 percent in this patient population.
Lorlatinib was generally tolerable. Most adverse events (AEs) were mild to moderate and managed with dose reductions, dose delays, or standard medical therapy. There were no treatment-related deaths and 3 percent of patients discontinued treatment due to drug-related AEs.
Hypercholesterolemia (81 percent) was the most common AE, followed by hypertriglyceridemia (60 percent), edema (43 percent), peripheral neuropathy (30 percent), weight increase (18 percent), cognitive effects (18 percent), mood effects (15 percent), fatigue (13 percent), diarrhea (11 percent), arthralgia (10 percent) and increased AST (10 percent).
Investigation into lorlatinib in NSCLC is continuing in the phase 3 CROWN trial. The open-label, randomized study is comparing lorlatinib to Xalkori in the first-line setting for patients with metastatic ALK-positive NSCLC. The targeted enrollment for the trial is 280 patients, and the study is being conducted at 221 locations.
No prior systemic treatment for NSCLC is allowed. Patients must have an ECOG performance status of 0, 1 or 2. Patients cannot enroll if they have had radiation therapy — including stereotactic or partial brain irradiation — within two weeks of randomization, or whole brain irradiation within four weeks of randomization. The primary outcome measure is progression-free survival. Secondary endpoints include overall survival, ORR, IC-ORR, time to tumor response and safety.