GENEVA (FRONTLINE MEDICAL NEWS) – Second-generation inhibitors of the anaplastic lymphoma kinase (ALK) are associated with high response rates in patients with non–small cell lung cancer (NSCLC) who have disease progression after treatment with the first-generation ALK inhibitor crizotinib (Xalkori), investigators reported.
Of 117 patients with ALK-positive NSCLC that progressed while on treatment with the ALK-targeting tyrosine-kinase inhibitor (TKI) crizotinib, both ceritinib (Zykadia) and alectinib (Alecensa) were associated with high combined partial and complete response rates, reported Christian Britschgi, MD, PhD, of University Hospital Zürich, and his colleagues.
The investigators presented results of a retrospective review of outcomes in patients with ALK-positive NSCLC treated at one of four Swiss hospitals and one Italian hospital – the so-called transalpine cohort – in a scientific poster session at the European Lung Cancer Conference.
“We can confirm the high rate of response of ceritinib and alectinib as second TKIs,” Dr. Britschgi said in an interview.
“With ceritinib or alectinib in the first line, however, it’s hard to draw any conclusions because there are very few patients treated with these drugs in the first line who were included in the trials,” he added.
ALK rearrangements occur in 3%-5% of lung adenocarcinomas, and these mutations are potential targets for TKIs directed against ALK.
The investigators analyzed the clinical characteristics of response to, and disease progression on, available ALK-TKIs. They also performed next-generation sequencing on a small group of tumor samples to investigate mechanisms of resistance and to look for new mutations that could be targetable.
They collected data on patients with ALK-positive NSCLC who were receiving palliative care and looked at clinical data and biopsy samples collected before treatment, and where available, post–ALK-TKI therapy.
They collected clinical data on 139 patients, 117 of whom had undergone first-line treatment with chemotherapy (74%), ALK-TKIs (25%), or other therapies (1%). Of this group, 92 received second-line therapy – chemotherapy (17%), ALK-TKIs (74%), or immunotherapies/other (9%).
Third-line treatments were given to 55 patients, 20% of whom received chemotherapy, 75% of whom received ALK-TKIs, and 5% of whom received other therapies.
Twenty-four patients survived long enough to receive fourth-line treatments, which included chemotherapy in 8 patients (33%), ALK-TKIs in 15 (63%), or other therapies in 1 patient.
In all, 102 patients received crizotinib, all but one in the first line and the remaining patient in the second line. The overall response rate was 58.8% (59.4% for the 101 first-line patients). Median progression-free survival (PFS) in these patients was 11.7 months.
Ceritinib was given to 2 patients in the first line, 7 in the second line, and 28 in the third line. The overall response rate was 48.6% (50% in the two patients who received it in the first line, and 50% in patients who received it after crizotinib). The median PFS was 6.5 months.
For the 26 patients who received alectinib – 3 in the first line and 23 after crizotinib – the overall response rate was 100% when the drug was used in the first line, and 60.9% when used in the second and subsequent lines. Median PFS was 12.4 months.
Only a few patients to date have had next-generation sequencing of tumors performed, Dr. Britschgi said. One patient who developed resistance while on alectinib was found to have a point mutation (ALK p.lle117Ser) that was not found in a pretreatment biopsy sample, indicating that it had emerged during therapy. This patient was then started on and had a response to lorlatinib.
A second patient who had received several lines of therapy including chemotherapy and TKIs and was enrolled in the expanded access program for lorlatinib developed hepatic progression while on that drug. A biopsy showed that the tumor carried epidermal growth-factor receptor variant 3, which is known to be highly mutagenic and is associated with glioblastoma. The patient was then put on nivolumab (Opdivo) and had a good response, but had further progression, and was then put on alectinib and again had a good response that is currently ongoing, Dr. Britschgi said.
The study was supported by University Hospital Zurich and Novartis. Dr. Britschgi reported no relevant disclosures. Coauthor Sacha Rothschild, MD, PhD, disclosed institutional compensation for advisory boards from Novartis, Pfizer and Roche.