CHICAGO – Having cancer is a known risk factor for thrombosis. A patient with cancer has a fourfold risk of developing venous thromboembolism (VTE).
This risk may be increased by certain cancer drugs, which seems to be the case for the combination of innovative targeted therapies lazertinib-amivantamab, as shown in patients with advanced or metastatic non–small cell lung cancer.
A study of this increased risk of VTE was presented by Nicolas Girard, MD, a respiratory medicine specialist at Curie-Montsouris Chest Center in Paris, during the annual meeting of the American Society of Clinical Oncology.
Combination therapies
Amivantamab is an EGFR and cMET bispecific antibody, and lazertinib is a third-generation EGFR tyrosine kinase inhibitor. Prescribed after osimertinib or after osimertinib plus chemotherapy, this combination of amivantamab and lazertinib has been evaluated in several cohorts of patients with EGFR-mutated advanced non–small cell lung cancer in whom targeted therapy and chemotherapy has failed.
The antitumor activity appears to be improved when both therapies are given in combination. The side effects generally are acceptable. It is these side effects, particularly the rate of VTEs, that Dr. Girard and his colleagues are interested in.
The researchers collated the data from the ongoing CHRYSALIS, CHRYSALIS-2, and LASER201 clinical trials, which assess the efficacy of these new agents as monotherapy or in combination. They initially investigated all reported thrombotic events and ruled out those that occurred during or after the 30 days before disease progression.
Increased thrombosis risk
The analysis included 560 patients who had been given amivantamab as monotherapy, 536 patients who had received amivantamab plus lazertinib in combination, and 252 who had taken lazertinib as monotherapy. The incidence of thromboembolic events was higher among patients who received amivantamab plus lazertinib in combination (21%) than in those who were given amivantamab (11%) or lazertinib (11%) as monotherapy.
The first thromboembolic event occurred an average of 84.5 days after starting treatment with amivantamab, 79 days after starting the combination therapy, and 170 days after starting treatment with lazertinib. For the amivantamab plus lazertinib combination, most VTEs developed in the first 4 months of treatment. The most common VTEs were pulmonary embolism and deep vein thrombosis.
The incidence of severe thrombotic events (grade ≥ 3), which was relatively low (amivantamab, 5%; amivantamab plus lazertinib, 6%; lazertinib, 6%) was similar regardless of the treatment, and there were no grade 5 thrombotic events among patients treated with the combination of both targeted therapies.
The significant risk factors for VTEs identified in this study were being age 60 years or older, having a score of 1 on the ECOG Performance Status Scale, and response to treatment (P < .05).
At a press conference organized by the Institut Curie before the ASCO conference, Dr. Girard said, “There has been shown to be an increased risk of blood clots with the use of this combination of targeted therapies. Preventive measures should therefore also be put forward, such as adding anticoagulant medication. This is an important study for the further development of these therapies.”
In a press release, the respiratory medicine specialist noted, “Institut Curie is particularly alert to the issue of the risk of thrombosis arising in cancer patients.” The DASTO project, dedicated to this issue and headed by the Institut Curie, “aims to cross-reference data sourced from several French cancer centers with data from the social security system to understand the risk factors, improve patient treatment, make changes to the care pathway, and prevent this unwanted occurrence from arising.”
Dr. Girard has direct links with Amgen, AstraZeneca, AbbVie, BMS, Daiichi Sankyo, Ipsen, Janssen, Roche, Lilly, Medtronic, MSD, Novartis, OSE Pharma, Pfizer, Sanofi, and Sivan.
This article was translated from the Medscape French Edition. A version of this article appeared on Medscape.com.