Phase 1 first in-human clinical trial with a therapeutic ALK vaccine in patients with ALK+ NSCLC

2020

ALK Positive

Mark Awad, MD, PhD

Dana-Farber Cancer Institute

Boston

Roberto Chiarle, MD

Harvard University

Cambridge

Research Summary

About 5% of non-small cell lung cancers (NSCLCs) have DNA mutations in the anaplastic lymphoma kinase (ALK) gene, and patients with this “ALK-positive” subtype of lung cancer are typically young and have never, or only lightly, smoked. For ALK-positive NSCLC, there are a number of FDA-approved oral ALK inhibitor pills, including alectinib, lorlatinib, and brigatinib. While these targeted therapies are initially very effective, the benefit of each of these drugs is usually limited to only a few years because ALK-positive lung cancers almost always develop drug resistance through a variety of complex mechanisms. Although PD-1 inhibitors such as pembrolizumab (Keytruda) have revolutionized the treatment of lung cancer in general, particularly in smoking-associated cancers, most patients with ALK-positive lung cancer do not respond to existing immunotherapies.

We developed an ALK vaccine immunotherapy, composed of small pieces of the ALK protein, which is an effective treatment in animal models of ALK-positive lung cancer. We now plan to launch a first-in-human clinical trial to test this ALK vaccine in patients whose cancer is growing despite treatment with an ALK inhibitor. The vaccine will be tested in combination with an approved ALK inhibitor or with an approved immunotherapy (pembrolizumab). We will also study immune cells in the blood and in tumor biopsies both before and after vaccination to ensure that this novel therapy is generating a proper anti-ALK immunologic response as we would expect. Our goal is to develop a safe and potent ALK vaccine to improve outcomes for our patients.

Technical Abstract

Several tyrosine kinase inhibitors (TKIs) are available for the treatment of ALK+ NSCLC, but resistance to all ALK TKIs (including alectinib, brigatinib, lorlatinib) has been reported and occurs through a variety of mechanisms. Once patients develop resistance to available ALK inhibitors, they are typically treated with cytotoxic chemotherapy rather than immunotherapy since response rates to PD-1 pathway inhibitors in this population are very low. However, our work in mouse models of ALK+ NSCLC has demonstrated that a vaccine generated against the rearranged portion of ALK can both prevent the development of ALK+ tumors and also more effectively treat them once they arise. We have also recently found evidence for anti-ALK immune responses in patients, as a subset of them generate spontaneous ALK autoantibodies.

We aim to translate our preclinical findings to a first-in-human clinical trial. Aim 1 will test the safety and efficacy of a novel ALK vaccine + an amphiphilic CpG toll-like receptor 9 agonist adjuvant, administered in combination with an ALK TKI or PD-1 inhibitor in patients with TKI-resistant ALK-positive NSCLC. In Aim 2, using liquid chromatography data-independent acquisition mass spectrometry, we will directly identify antigenic ALK peptides presented by MHC molecules on the surface of cancer cells from tumor biopsies obtained on trial participants. In Aim 3, we will study pre- and post-vaccination anti-ALK T-cell responses among trial participants by analyzing peripheral leukocytes and intratumoral immune cells. The overarching goal is to develop a vaccine that stimulates patients’ immune cells to recognize and eliminate ALK+ tumors.

Key words

Acquired resistance

Anaplastic lymphoma kinase (ALK)

Biomarker or biomarker testing

Immunotherapy

Metastatic

Non-small cell lung cancer (NSCLC)

Stage III

Stage IV

Tumor microenvironment

Tyrosine kinase inhibitors (TKIs)